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CONFIG_TEGRA_PARTITION with tegra132 #9

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MartijnBraam opened this issue Aug 24, 2020 · 5 comments
Open

CONFIG_TEGRA_PARTITION with tegra132 #9

MartijnBraam opened this issue Aug 24, 2020 · 5 comments

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@MartijnBraam
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I'm trying to make mainline linux work on the nexus 9, continueing on the work already done on https://wiki.postmarketos.org/wiki/Google_Nexus_9_(htc-flounder)

I managed to make the eMMC recognized in the kernel by adding it to the dts but I'm having issues making it recognize the gpt partitions. It seems like the tegra partitions thing doesn't work at all yet on tegra132, the bootloader does pass the gpt and gpt_sector= but not tegraboot=sdmmc. Worked around that by manually adding tegraboot to the cmdline in boot.img

This is the changes I made so far: MartijnBraam@ab0d237

The current issue I have is that nvidia,tegra124-sdhci doesn't have the memory address as only value so just duplicating the code doesn't work.

@digetx
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digetx commented Aug 24, 2020

Hello @MartijnBraam! Nice work on getting TegraPT to work on Nexus 9! I didn't even know that TegraPT is needed for Nexus 9. The code change looks good to me, I can incorporate it into grate-kernel on next update. I suppose you may add tegraboot=sdmmc to the bootargs in the device-tree in order to avoid changing cmdline of the bootimg, couldn't you? The kernel needs to know whether it's okay to check eMMC for the TegraPT and the cmdline parameter is the best option for now. It's a bit unfortunate that Tegra bootloaders are inconsistent, but that's what we have and need to deal with it :)

@digetx
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digetx commented Aug 24, 2020

Oh, wait! Seems you haven't got it to work yet. Could you please clarify what do you mean by the memory address as only value?

@digetx
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digetx commented Aug 24, 2020

Ah, I see now. Could you please try this change:

diff --git a/block/partitions/tegra.c b/block/partitions/tegra.c
index a2ccd644e377..e754159d91e8 100644
--- a/block/partitions/tegra.c
+++ b/block/partitions/tegra.c
@@ -21,6 +21,7 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
 #include <linux/string.h>
@@ -456,9 +457,9 @@ tegra_partition_table_emmc_boot_offset(struct tegra_partition_table_parser *ptp)
 	struct mmc_card *card = mmc_bdev_to_card(ptp->state->bdev);
 	const struct of_device_id *matched;
 	const u32 *sdhci_bases;
+	const __be32 *addrp;
 	u32 sdhci_base;
 	unsigned int i;
-	int err;
 
 	/* filter out unexpected/untested boot sources */
 	if (!card || card->ext_csd.rev < 3 ||
@@ -477,11 +478,12 @@ tegra_partition_table_emmc_boot_offset(struct tegra_partition_table_parser *ptp)
 	sdhci_bases = matched->data;
 
 	/* figure out SDHCI instance ID by the base address */
-	err = of_property_read_u32_index(card->host->parent->of_node,
-					 "reg", 0, &sdhci_base);
-	if (err)
+	addrp = of_get_address(card->host->parent->of_node, 0, NULL, NULL);
+	if (!addrp)
 		return -1;
 
+	sdhci_base = of_translate_address(card->host->parent->of_node, addrp);
+
 	for (i = 0; i < TEGRA_PT_SDHCI_DEVICE_INSTANCES; i++) {
 		if (sdhci_base == sdhci_bases[i])
 			break;

@MartijnBraam
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MartijnBraam commented Aug 24, 2020

Yep that seems to work great, combined the changes in here: MartijnBraam@c87728d

Now I'm out of the initramfs at least :)

This is in my kernel log with the change:

[    2.269896] Primary GPT is invalid, using alternate GPT
[    2.278858]  mmcblk0: p1 p2 p3 p4 p5 p6 p7 p8 p9 p10 p11 p12 p13 p14 p15 p16 p17 p18 p19 p20 p21 p22 p23 p24 p25 p26 p27 p28 p29 p30 p31 p32 p33

@digetx
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digetx commented Aug 25, 2020

Awesome!

Wow, Nexus 9 has 33 partitions? Crazy :)

okias pushed a commit to okias/linux that referenced this issue Sep 3, 2020
…s metrics" test

Linux 5.9 introduced perf test case "Parse and process metrics" and
on s390 this test case always dumps core:

  [root@t35lp67 perf]# ./perf test -vvvv -F 67
  67: Parse and process metrics                             :
  --- start ---
  metric expr inst_retired.any / cpu_clk_unhalted.thread for IPC
  parsing metric: inst_retired.any / cpu_clk_unhalted.thread
  Segmentation fault (core dumped)
  [root@t35lp67 perf]#

I debugged this core dump and gdb shows this call chain:

  (gdb) where
   #0  0x000003ffabc3192a in __strnlen_c_1 () from /lib64/libc.so.6
   #1  0x000003ffabc293de in strcasestr () from /lib64/libc.so.6
   #2  0x0000000001102ba2 in match_metric(list=0x1e6ea20 "inst_retired.any",
            n=<optimized out>)
       at util/metricgroup.c:368
   #3  find_metric (map=<optimized out>, map=<optimized out>,
           metric=0x1e6ea20 "inst_retired.any")
      at util/metricgroup.c:765
   #4  __resolve_metric (ids=0x0, map=<optimized out>, metric_list=0x0,
           metric_no_group=<optimized out>, m=<optimized out>)
      at util/metricgroup.c:844
   #5  resolve_metric (ids=0x0, map=0x0, metric_list=0x0,
          metric_no_group=<optimized out>)
      at util/metricgroup.c:881
   #6  metricgroup__add_metric (metric=<optimized out>,
        metric_no_group=metric_no_group@entry=false, events=<optimized out>,
        events@entry=0x3ffd84fb878, metric_list=0x0,
        metric_list@entry=0x3ffd84fb868, map=0x0)
      at util/metricgroup.c:943
   #7  0x00000000011034ae in metricgroup__add_metric_list (map=0x13f9828 <map>,
        metric_list=0x3ffd84fb868, events=0x3ffd84fb878,
        metric_no_group=<optimized out>, list=<optimized out>)
      at util/metricgroup.c:988
   #8  parse_groups (perf_evlist=perf_evlist@entry=0x1e70260,
          str=str@entry=0x12f34b2 "IPC", metric_no_group=<optimized out>,
          metric_no_merge=<optimized out>,
          fake_pmu=fake_pmu@entry=0x1462f18 <perf_pmu.fake>,
          metric_events=0x3ffd84fba58, map=0x1)
      at util/metricgroup.c:1040
   grate-driver#9  0x0000000001103eb2 in metricgroup__parse_groups_test(
  	evlist=evlist@entry=0x1e70260, map=map@entry=0x13f9828 <map>,
  	str=str@entry=0x12f34b2 "IPC",
  	metric_no_group=metric_no_group@entry=false,
  	metric_no_merge=metric_no_merge@entry=false,
  	metric_events=0x3ffd84fba58)
      at util/metricgroup.c:1082
   grate-driver#10 0x00000000010c84d8 in __compute_metric (ratio2=0x0, name2=0x0,
          ratio1=<synthetic pointer>, name1=0x12f34b2 "IPC",
  	vals=0x3ffd84fbad8, name=0x12f34b2 "IPC")
      at tests/parse-metric.c:159
   grate-driver#11 compute_metric (ratio=<synthetic pointer>, vals=0x3ffd84fbad8,
  	name=0x12f34b2 "IPC")
      at tests/parse-metric.c:189
   grate-driver#12 test_ipc () at tests/parse-metric.c:208
.....
..... omitted many more lines

This test case was added with
commit 218ca91 ("perf tests: Add parse metric test for frontend metric").

When I compile with make DEBUG=y it works fine and I do not get a core dump.

It turned out that the above listed function call chain worked on a struct
pmu_event array which requires a trailing element with zeroes which was
missing. The marco map_for_each_event() loops over that array tests for members
metric_expr/metric_name/metric_group being non-NULL. Adding this element fixes
the issue.

Output after:

  [root@t35lp46 perf]# ./perf test 67
  67: Parse and process metrics                             : Ok
  [root@t35lp46 perf]#

Committer notes:

As Ian remarks, this is not s390 specific:

<quote Ian>
  This also shows up with address sanitizer on all architectures
  (perhaps change the patch title) and perhaps add a "Fixes: <commit>"
  tag.

  =================================================================
  ==4718==ERROR: AddressSanitizer: global-buffer-overflow on address
  0x55c93b4d59e8 at pc 0x55c93a1541e2 bp 0x7ffd24327c60 sp
  0x7ffd24327c58
  READ of size 8 at 0x55c93b4d59e8 thread T0
      #0 0x55c93a1541e1 in find_metric tools/perf/util/metricgroup.c:764:2
      #1 0x55c93a153e6c in __resolve_metric tools/perf/util/metricgroup.c:844:9
      #2 0x55c93a152f18 in resolve_metric tools/perf/util/metricgroup.c:881:9
      #3 0x55c93a1528db in metricgroup__add_metric
  tools/perf/util/metricgroup.c:943:9
      #4 0x55c93a151996 in metricgroup__add_metric_list
  tools/perf/util/metricgroup.c:988:9
      #5 0x55c93a1511b9 in parse_groups tools/perf/util/metricgroup.c:1040:8
      #6 0x55c93a1513e1 in metricgroup__parse_groups_test
  tools/perf/util/metricgroup.c:1082:9
      #7 0x55c93a0108ae in __compute_metric tools/perf/tests/parse-metric.c:159:8
      #8 0x55c93a010744 in compute_metric tools/perf/tests/parse-metric.c:189:9
      grate-driver#9 0x55c93a00f5ee in test_ipc tools/perf/tests/parse-metric.c:208:2
      grate-driver#10 0x55c93a00f1e8 in test__parse_metric
  tools/perf/tests/parse-metric.c:345:2
      grate-driver#11 0x55c939fd7202 in run_test tools/perf/tests/builtin-test.c:410:9
      grate-driver#12 0x55c939fd6736 in test_and_print tools/perf/tests/builtin-test.c:440:9
      grate-driver#13 0x55c939fd58c3 in __cmd_test tools/perf/tests/builtin-test.c:661:4
      grate-driver#14 0x55c939fd4e02 in cmd_test tools/perf/tests/builtin-test.c:807:9
      grate-driver#15 0x55c939e4763d in run_builtin tools/perf/perf.c:313:11
      grate-driver#16 0x55c939e46475 in handle_internal_command tools/perf/perf.c:365:8
      grate-driver#17 0x55c939e4737e in run_argv tools/perf/perf.c:409:2
      grate-driver#18 0x55c939e45f7e in main tools/perf/perf.c:539:3

  0x55c93b4d59e8 is located 0 bytes to the right of global variable
  'pme_test' defined in 'tools/perf/tests/parse-metric.c:17:25'
  (0x55c93b4d54a0) of size 1352
  SUMMARY: AddressSanitizer: global-buffer-overflow
  tools/perf/util/metricgroup.c:764:2 in find_metric
  Shadow bytes around the buggy address:
    0x0ab9a7692ae0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692af0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  =>0x0ab9a7692b30: 00 00 00 00 00 00 00 00 00 00 00 00 00[f9]f9 f9
    0x0ab9a7692b40: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
    0x0ab9a7692b50: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
    0x0ab9a7692b60: f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 00 00 00 00
    0x0ab9a7692b70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
  Shadow byte legend (one shadow byte represents 8 application bytes):
    Addressable:           00
    Partially addressable: 01 02 03 04 05 06 07
    Heap left redzone:	   fa
    Freed heap region:	   fd
    Stack left redzone:	   f1
    Stack mid redzone:	   f2
    Stack right redzone:     f3
    Stack after return:	   f5
    Stack use after scope:   f8
    Global redzone:          f9
    Global init order:	   f6
    Poisoned by user:        f7
    Container overflow:	   fc
    Array cookie:            ac
    Intra object redzone:    bb
    ASan internal:           fe
    Left alloca redzone:     ca
    Right alloca redzone:    cb
    Shadow gap:              cc
</quote>

I'm also adding the missing "Fixes" tag and setting just .name to NULL,
as doing it that way is more compact (the compiler will zero out
everything else) and the table iterators look for .name being NULL as
the sentinel marking the end of the table.

Fixes: 0a507af ("perf tests: Add parse metric test for ipc metric")
Signed-off-by: Thomas Richter <[email protected]>
Reviewed-by: Sumanth Korikkar <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Sep 3, 2020
This addresses a bug in the irqchip core that was triggered
by new code assuming a strict semantic order of the irqchip
calls:

 .irq_request_resources()
 .irq_enable()
 .irq_disable()
 .irq_release_resources()

Mostly this is working fine when handled inside manage.c,
the calls are strictly happening in the above assumed order.

However on a Qualcomm platform I get the following in dmesg:

WARNING: CPU: 0 PID: 1 at ../drivers/gpio/gpiolib.c:3513
	 gpiochip_irq_enable+0x18/0x44
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0
     Not tainted 4.20.0-rc4-00002-g1b8a75b25c6e-dirty grate-driver#9
Hardware name: Generic DT based system
[<c03124ac>] (unwind_backtrace) from [<c030d994>] (show_stack+0x10/0x14)
[<c030d994>] (show_stack) from [<c0b48aec>] (dump_stack+0x78/0x8c)
[<c0b48aec>] (dump_stack) from [<c03213e4>] (__warn+0xe0/0xf8)
[<c03213e4>] (__warn) from [<c0321514>] (warn_slowpath_null+0x40/0x48)
[<c0321514>] (warn_slowpath_null) from [<c06ad5d0>]
	     (gpiochip_irq_enable+0x18/0x44)
[<c06ad5d0>] (gpiochip_irq_enable) from [<c0371198>] (irq_enable+0x44/0x64)
[<c0371198>] (irq_enable) from [<c0371258>] (__irq_startup+0xa0/0xa8)
[<c0371258>] (__irq_startup) from [<c03712ac>] (irq_startup+0x4c/0x130)
[<c03712ac>] (irq_startup) from [<c03716d0>]
	     (irq_set_chained_handler_and_data+0x4c/0x78)
[<c03716d0>] (irq_set_chained_handler_and_data) from [<c081c17c>]
	     (pm8xxx_probe+0x160/0x22c)
[<c081c17c>] (pm8xxx_probe) from [<c07f439c>] (platform_drv_probe+0x48/0x98)

What happens is that when the pm8xxx driver tries to register
a chained IRQ irq_set_chained_handler_and_data() will eventually
set the type and call irq_startup() and thus the .irq_enable()
callback on the irqchip.

This irqchip is in drivers/pinctrl/qcom/pinctrl-msm.c and known
as TLMM.

However, the irqchip core helpers in GPIO assumes that
the .irq_request_resources() callback is always called before
.irq_enable(), and the latter is where module refcount and
also gpiochip_lock_as_irq() is normally called.

When .irq_enable() is called without .irq_request_resources()
having been called first, it seems like we are enabling
an IRQ on a GPIO line that has not first been locked to be
used as IRQ and we get the above warning. This happens since
as of
commit 461c1a7 ("gpiolib: override irq_enable/disable")
this is strictly assumed for all GPIO-based IRQs.

As it seems reasonable to assume that .irq_request_resources()
is always strictly called before .irq_enable(), we add the
irq_[request|release]_resources() functions to the internal
API and call them also when adding a chained irqchip to
an IRQ.

I am a bit uncertain about the call site for
irq_released_resources() inside chip.c, but it appears this
path is for uninstalling a chained handler.

Cc: [email protected]
Cc: Bjorn Andersson <[email protected]>
Cc: Hans Verkuil <[email protected]>
Fixes: 461c1a7 ("gpiolib: override irq_enable/disable")
Signed-off-by: Linus Walleij <[email protected]>
digetx pushed a commit that referenced this issue Sep 12, 2020
Krzysztof Kozlowski says:

====================
nfc: s3fwrn5: Few cleanups

Changes since v2:
1. Fix dtschema ID after rename (patch 1/8).
2. Apply patch 9/9 (defconfig change).

Changes since v1:
1. Rename dtschema file and add additionalProperties:false, as Rob
   suggested,
2. Add Marek's tested-by,
3. New patches: #4, #5, #6, #7 and #9.
====================

Signed-off-by: David S. Miller <[email protected]>
digetx pushed a commit that referenced this issue Sep 28, 2020
Huazhong Tan says:

====================
net: hns3: updates for -next

To facilitate code maintenance and compatibility, #1 and #2 add
device version to replace pci revision, #3 to #9 adds support for
querying device capabilities and specifications, then the driver
can use these query results to implement corresponding features
(some features will be implemented later).

And #10 is a minor cleanup since too many parameters for
hclge_shaper_para_calc().
====================

Signed-off-by: David S. Miller <[email protected]>
digetx pushed a commit that referenced this issue Sep 28, 2020
Ido Schimmel says:

====================
mlxsw: Expose transceiver overheat counter

Amit says:

An overheated transceiver can be the root cause of various network
problems such as link flapping. Counting the number of times a
transceiver's temperature was higher than its configured threshold can
therefore help in debugging such issues.

This patch set exposes a transceiver overheat counter via ethtool. This
is achieved by configuring the Spectrum ASIC to generate events whenever
a transceiver is overheated. The temperature thresholds are queried from
the transceiver (if available) and set to the default otherwise.

Example:

...
transceiver_overheat: 2

Patch set overview:

Patches #1-#3 add required device registers
Patches #4-#5 add required infrastructure in mlxsw to configure and
count overheat events
Patches #6-#9 gradually add support for the transceiver overheat counter
Patch #10 exposes the transceiver overheat counter via ethtool
====================

Signed-off-by: David S. Miller <[email protected]>
digetx pushed a commit that referenced this issue Oct 15, 2020
The following lockdep splat

======================================================
WARNING: possible circular locking dependency detected
5.8.0-rc7-00169-g87212851a027-dirty #929 Not tainted
------------------------------------------------------
fsstress/8739 is trying to acquire lock:
ffff88bfd0eb0c90 (&fs_info->reloc_mutex){+.+.}-{3:3}, at: btrfs_record_root_in_trans+0x43/0x70

but task is already holding lock:
ffff88bfbd16e538 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x6a/0x4a0

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #10 (sb_pagefaults){.+.+}-{0:0}:
       __sb_start_write+0x129/0x210
       btrfs_page_mkwrite+0x6a/0x4a0
       do_page_mkwrite+0x4d/0xc0
       handle_mm_fault+0x103c/0x1730
       exc_page_fault+0x340/0x660
       asm_exc_page_fault+0x1e/0x30

-> #9 (&mm->mmap_lock#2){++++}-{3:3}:
       __might_fault+0x68/0x90
       _copy_to_user+0x1e/0x80
       perf_read+0x141/0x2c0
       vfs_read+0xad/0x1b0
       ksys_read+0x5f/0xe0
       do_syscall_64+0x50/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

-> #8 (&cpuctx_mutex){+.+.}-{3:3}:
       __mutex_lock+0x9f/0x930
       perf_event_init_cpu+0x88/0x150
       perf_event_init+0x1db/0x20b
       start_kernel+0x3ae/0x53c
       secondary_startup_64+0xa4/0xb0

-> #7 (pmus_lock){+.+.}-{3:3}:
       __mutex_lock+0x9f/0x930
       perf_event_init_cpu+0x4f/0x150
       cpuhp_invoke_callback+0xb1/0x900
       _cpu_up.constprop.26+0x9f/0x130
       cpu_up+0x7b/0xc0
       bringup_nonboot_cpus+0x4f/0x60
       smp_init+0x26/0x71
       kernel_init_freeable+0x110/0x258
       kernel_init+0xa/0x103
       ret_from_fork+0x1f/0x30

-> #6 (cpu_hotplug_lock){++++}-{0:0}:
       cpus_read_lock+0x39/0xb0
       kmem_cache_create_usercopy+0x28/0x230
       kmem_cache_create+0x12/0x20
       bioset_init+0x15e/0x2b0
       init_bio+0xa3/0xaa
       do_one_initcall+0x5a/0x2e0
       kernel_init_freeable+0x1f4/0x258
       kernel_init+0xa/0x103
       ret_from_fork+0x1f/0x30

-> #5 (bio_slab_lock){+.+.}-{3:3}:
       __mutex_lock+0x9f/0x930
       bioset_init+0xbc/0x2b0
       __blk_alloc_queue+0x6f/0x2d0
       blk_mq_init_queue_data+0x1b/0x70
       loop_add+0x110/0x290 [loop]
       fq_codel_tcf_block+0x12/0x20 [sch_fq_codel]
       do_one_initcall+0x5a/0x2e0
       do_init_module+0x5a/0x220
       load_module+0x2459/0x26e0
       __do_sys_finit_module+0xba/0xe0
       do_syscall_64+0x50/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

-> #4 (loop_ctl_mutex){+.+.}-{3:3}:
       __mutex_lock+0x9f/0x930
       lo_open+0x18/0x50 [loop]
       __blkdev_get+0xec/0x570
       blkdev_get+0xe8/0x150
       do_dentry_open+0x167/0x410
       path_openat+0x7c9/0xa80
       do_filp_open+0x93/0x100
       do_sys_openat2+0x22a/0x2e0
       do_sys_open+0x4b/0x80
       do_syscall_64+0x50/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

-> #3 (&bdev->bd_mutex){+.+.}-{3:3}:
       __mutex_lock+0x9f/0x930
       blkdev_put+0x1d/0x120
       close_fs_devices.part.31+0x84/0x130
       btrfs_close_devices+0x44/0xb0
       close_ctree+0x296/0x2b2
       generic_shutdown_super+0x69/0x100
       kill_anon_super+0xe/0x30
       btrfs_kill_super+0x12/0x20
       deactivate_locked_super+0x29/0x60
       cleanup_mnt+0xb8/0x140
       task_work_run+0x6d/0xb0
       __prepare_exit_to_usermode+0x1cc/0x1e0
       do_syscall_64+0x5c/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

-> #2 (&fs_devs->device_list_mutex){+.+.}-{3:3}:
       __mutex_lock+0x9f/0x930
       btrfs_run_dev_stats+0x49/0x480
       commit_cowonly_roots+0xb5/0x2a0
       btrfs_commit_transaction+0x516/0xa60
       sync_filesystem+0x6b/0x90
       generic_shutdown_super+0x22/0x100
       kill_anon_super+0xe/0x30
       btrfs_kill_super+0x12/0x20
       deactivate_locked_super+0x29/0x60
       cleanup_mnt+0xb8/0x140
       task_work_run+0x6d/0xb0
       __prepare_exit_to_usermode+0x1cc/0x1e0
       do_syscall_64+0x5c/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

-> #1 (&fs_info->tree_log_mutex){+.+.}-{3:3}:
       __mutex_lock+0x9f/0x930
       btrfs_commit_transaction+0x4bb/0xa60
       sync_filesystem+0x6b/0x90
       generic_shutdown_super+0x22/0x100
       kill_anon_super+0xe/0x30
       btrfs_kill_super+0x12/0x20
       deactivate_locked_super+0x29/0x60
       cleanup_mnt+0xb8/0x140
       task_work_run+0x6d/0xb0
       __prepare_exit_to_usermode+0x1cc/0x1e0
       do_syscall_64+0x5c/0x90
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

-> #0 (&fs_info->reloc_mutex){+.+.}-{3:3}:
       __lock_acquire+0x1272/0x2310
       lock_acquire+0x9e/0x360
       __mutex_lock+0x9f/0x930
       btrfs_record_root_in_trans+0x43/0x70
       start_transaction+0xd1/0x5d0
       btrfs_dirty_inode+0x42/0xd0
       file_update_time+0xc8/0x110
       btrfs_page_mkwrite+0x10c/0x4a0
       do_page_mkwrite+0x4d/0xc0
       handle_mm_fault+0x103c/0x1730
       exc_page_fault+0x340/0x660
       asm_exc_page_fault+0x1e/0x30

other info that might help us debug this:

Chain exists of:
  &fs_info->reloc_mutex --> &mm->mmap_lock#2 --> sb_pagefaults

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(sb_pagefaults);
                               lock(&mm->mmap_lock#2);
                               lock(sb_pagefaults);
  lock(&fs_info->reloc_mutex);

 *** DEADLOCK ***

3 locks held by fsstress/8739:
 #0: ffff88bee66eeb68 (&mm->mmap_lock#2){++++}-{3:3}, at: exc_page_fault+0x173/0x660
 #1: ffff88bfbd16e538 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x6a/0x4a0
 #2: ffff88bfbd16e630 (sb_internal){.+.+}-{0:0}, at: start_transaction+0x3da/0x5d0

stack backtrace:
CPU: 17 PID: 8739 Comm: fsstress Kdump: loaded Not tainted 5.8.0-rc7-00169-g87212851a027-dirty #929
Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018
Call Trace:
 dump_stack+0x78/0xa0
 check_noncircular+0x165/0x180
 __lock_acquire+0x1272/0x2310
 ? btrfs_get_alloc_profile+0x150/0x210
 lock_acquire+0x9e/0x360
 ? btrfs_record_root_in_trans+0x43/0x70
 __mutex_lock+0x9f/0x930
 ? btrfs_record_root_in_trans+0x43/0x70
 ? lock_acquire+0x9e/0x360
 ? join_transaction+0x5d/0x450
 ? find_held_lock+0x2d/0x90
 ? btrfs_record_root_in_trans+0x43/0x70
 ? join_transaction+0x3d5/0x450
 ? btrfs_record_root_in_trans+0x43/0x70
 btrfs_record_root_in_trans+0x43/0x70
 start_transaction+0xd1/0x5d0
 btrfs_dirty_inode+0x42/0xd0
 file_update_time+0xc8/0x110
 btrfs_page_mkwrite+0x10c/0x4a0
 ? handle_mm_fault+0x5e/0x1730
 do_page_mkwrite+0x4d/0xc0
 ? __do_fault+0x32/0x150
 handle_mm_fault+0x103c/0x1730
 exc_page_fault+0x340/0x660
 ? asm_exc_page_fault+0x8/0x30
 asm_exc_page_fault+0x1e/0x30
RIP: 0033:0x7faa6c9969c4

Was seen in testing.  The fix is similar to that of

  btrfs: open device without device_list_mutex

where we're holding the device_list_mutex and then grab the bd_mutex,
which pulls in a bunch of dependencies under the bd_mutex.  We only ever
call btrfs_close_devices() on mount failure or unmount, so we're save to
not have the device_list_mutex here.  We're already holding the
uuid_mutex which keeps us safe from any external modification of the
fs_devices.

Signed-off-by: Josef Bacik <[email protected]>
Signed-off-by: David Sterba <[email protected]>
digetx pushed a commit that referenced this issue Oct 15, 2020
[BUG]
With a crafted image, btrfs can panic at insert_inline_extent_backref():

  kernel BUG at fs/btrfs/extent-tree.c:1857!
  invalid opcode: 0000 [#1] SMP PTI
  CPU: 0 PID: 1117 Comm: btrfs-transacti Not tainted 5.0.0-rc8+ #9
  RIP: 0010:insert_inline_extent_backref+0xcc/0xe0
  RSP: 0018:ffffac4dc1287be8 EFLAGS: 00010293
  RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000000001
  RDX: 0000000000001000 RSI: 0000000000000000 RDI: 0000000000000000
  RBP: ffffac4dc1287c28 R08: ffffac4dc1287ab8 R09: ffffac4dc1287ac0
  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
  R13: ffff8febef88a540 R14: ffff8febeaa7bc30 R15: 0000000000000000
  FS: 0000000000000000(0000) GS:ffff8febf7a00000(0000) knlGS:0000000000000000
  CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f663ace94c0 CR3: 0000000235698006 CR4: 00000000000206f0
  Call Trace:
  ? _cond_resched+0x1a/0x50
  __btrfs_inc_extent_ref.isra.64+0x7e/0x240
  ? btrfs_merge_delayed_refs+0xa5/0x330
  __btrfs_run_delayed_refs+0x653/0x1120
  btrfs_run_delayed_refs+0xdb/0x1b0
  btrfs_commit_transaction+0x52/0x950
  ? start_transaction+0x94/0x450
  transaction_kthread+0x163/0x190
  kthread+0x105/0x140
  ? btrfs_cleanup_transaction+0x560/0x560
  ? kthread_destroy_worker+0x50/0x50
  ret_from_fork+0x35/0x40
  Modules linked in:
  ---[ end trace 2ad8b3de903cf825 ]---

[CAUSE]
Due to extent tree corruption (still valid by itself, but bad cross
ref), we can allocate an extent which is still in extent tree.  The
offending tree block of that case is from csum tree.  The newly
allocated tree block is also for csum tree.

Then we will try to insert a tree block ref for the existing tree block
ref.

For a tree extent item, tree block can never be shared directly by the
same tree twice.  We have such BUG_ON() to prevent such problem, but
this is not a proper error handling.

[FIX]
Replace that BUG_ON() with proper error message and leaf dump for debug
build.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202829
Reviewed-by: Nikolay Borisov <[email protected]>
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Qu Wenruo <[email protected]>
Signed-off-by: David Sterba <[email protected]>
digetx pushed a commit that referenced this issue Oct 15, 2020
[BUG]
With a crafted image, btrfs can panic at btrfs_del_csums():

  kernel BUG at fs/btrfs/ctree.c:3188!
  invalid opcode: 0000 [#1] SMP PTI
  CPU: 0 PID: 1156 Comm: btrfs-transacti Not tainted 5.0.0-rc8+ #9
  RIP: 0010:btrfs_set_item_key_safe+0x16c/0x180
  RSP: 0018:ffff976141257ab8 EFLAGS: 00010202
  RAX: 0000000000000001 RBX: ffff898a6b890930 RCX: 0000000004b70000
  RDX: 0000000000000000 RSI: ffff976141257bae RDI: ffff976141257acf
  RBP: ffff976141257b10 R08: 0000000000001000 R09: ffff9761412579a8
  R10: 0000000000000000 R11: 0000000000000000 R12: ffff976141257abe
  R13: 0000000000000003 R14: ffff898a6a8be578 R15: ffff976141257bae
  FS: 0000000000000000(0000) GS:ffff898a77a00000(0000) knlGS:0000000000000000
  CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f779d9cd624 CR3: 000000022b2b4006 CR4: 00000000000206f0
  Call Trace:
  truncate_one_csum+0xac/0xf0
  btrfs_del_csums+0x24f/0x3a0
  __btrfs_free_extent.isra.72+0x5a7/0xbe0
  __btrfs_run_delayed_refs+0x539/0x1120
  btrfs_run_delayed_refs+0xdb/0x1b0
  btrfs_commit_transaction+0x52/0x950
  ? start_transaction+0x94/0x450
  transaction_kthread+0x163/0x190
  kthread+0x105/0x140
  ? btrfs_cleanup_transaction+0x560/0x560
  ? kthread_destroy_worker+0x50/0x50
  ret_from_fork+0x35/0x40
  Modules linked in:
  ---[ end trace 93bf9db00e6c374e ]---

[CAUSE]
This crafted image has a tricky key order corruption:

  checksum tree key (CSUM_TREE ROOT_ITEM 0)
  node 29741056 level 1 items 14 free 107 generation 19 owner CSUM_TREE
          ...
          key (EXTENT_CSUM EXTENT_CSUM 73785344) block 29757440 gen 19
          key (EXTENT_CSUM EXTENT_CSUM 77594624) block 29753344 gen 19
          ...

  leaf 29757440 items 5 free space 150 generation 19 owner CSUM_TREE
          item 0 key (EXTENT_CSUM EXTENT_CSUM 73785344) itemoff 2323 itemsize 1672
                  range start 73785344 end 75497472 length 1712128
          item 1 key (EXTENT_CSUM EXTENT_CSUM 75497472) itemoff 2319 itemsize 4
                  range start 75497472 end 75501568 length 4096
          item 2 key (EXTENT_CSUM EXTENT_CSUM 75501568) itemoff 579 itemsize 1740
                  range start 75501568 end 77283328 length 1781760
          item 3 key (EXTENT_CSUM EXTENT_CSUM 77283328) itemoff 575 itemsize 4
                  range start 77283328 end 77287424 length 4096
          item 4 key (EXTENT_CSUM EXTENT_CSUM 4120596480) itemoff 275 itemsize 300 <<<
                  range start 4120596480 end 4120903680 length 307200
  leaf 29753344 items 3 free space 1936 generation 19 owner CSUM_TREE
          item 0 key (18446744073457893366 EXTENT_CSUM 77594624) itemoff 2323 itemsize 1672
                  range start 77594624 end 79306752 length 1712128
          ...

Note the item 4 key of leaf 29757440, which is obviously too large, and
even larger than the first key of the next leaf.

However it still follows the key order in that tree block, thus tree
checker is unable to detect it at read time, since tree checker can only
work inside one leaf, thus such complex corruption can't be detected in
advance.

[FIX]
The next time to detect such problem is at tree block merge time,
which is in push_node_left(), balance_node_right(), push_leaf_left() or
push_leaf_right().

Now we check if the key order of the right-most key of the left node is
larger than the left-most key of the right node.

By this we don't need to call the full tree-checker, while still keeping
the key order correct as key order in each node is already checked by
tree checker thus we only need to check the above two slots.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202833
Reviewed-by: Nikolay Borisov <[email protected]>
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Qu Wenruo <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
digetx pushed a commit that referenced this issue Oct 21, 2020
Like evlist cpu map, evsel's cpu map should have a proper refcount.

As it's created with a refcount, we don't need to get an extra count.
Thanks to Arnaldo for the simpler suggestion.

This, together with the following patch, fixes the following ASAN
report:

  Direct leak of 840 byte(s) in 70 object(s) allocated from:
    #0 0x7fe36703f628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628)
    #1 0x559fbbf611ca in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x559fbbf6229c in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:237
    #3 0x559fbbcc6c6d in __add_event util/parse-events.c:357
    #4 0x559fbbcc6c6d in add_event_tool util/parse-events.c:408
    #5 0x559fbbcc6c6d in parse_events_add_tool util/parse-events.c:1414
    #6 0x559fbbd8474d in parse_events_parse util/parse-events.y:439
    #7 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096
    #8 0x559fbbcc95da in __parse_events util/parse-events.c:2141
    #9 0x559fbbc2788b in check_parse_id tests/pmu-events.c:406
    #10 0x559fbbc2788b in check_parse_id tests/pmu-events.c:393
    #11 0x559fbbc2788b in check_parse_fake tests/pmu-events.c:436
    #12 0x559fbbc2788b in metric_parse_fake tests/pmu-events.c:553
    #13 0x559fbbc27e2d in test_parsing_fake tests/pmu-events.c:599
    #14 0x559fbbc27e2d in test_parsing_fake tests/pmu-events.c:574
    #15 0x559fbbc0109b in run_test tests/builtin-test.c:410
    #16 0x559fbbc0109b in test_and_print tests/builtin-test.c:440
    #17 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695
    #18 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807
    #19 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #20 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #21 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #22 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #23 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308

And I've failed which commit introduced this bug as the code was
heavily changed since then. ;-/

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Oct 21, 2020
Ensure 'st' is initialized before an error branch is taken.
Fixes test "67: Parse and process metrics" with LLVM msan:

  ==6757==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x5570edae947d in rblist__exit tools/perf/util/rblist.c:114:2
    #1 0x5570edb1c6e8 in runtime_stat__exit tools/perf/util/stat-shadow.c:141:2
    #2 0x5570ed92cfae in __compute_metric tools/perf/tests/parse-metric.c:187:2
    #3 0x5570ed92cb74 in compute_metric tools/perf/tests/parse-metric.c:196:9
    #4 0x5570ed92c6d8 in test_recursion_fail tools/perf/tests/parse-metric.c:318:2
    #5 0x5570ed92b8c8 in test__parse_metric tools/perf/tests/parse-metric.c:356:2
    #6 0x5570ed8de8c1 in run_test tools/perf/tests/builtin-test.c:410:9
    #7 0x5570ed8ddadf in test_and_print tools/perf/tests/builtin-test.c:440:9
    #8 0x5570ed8dca04 in __cmd_test tools/perf/tests/builtin-test.c:661:4
    #9 0x5570ed8dbc07 in cmd_test tools/perf/tests/builtin-test.c:807:9
    #10 0x5570ed7326cc in run_builtin tools/perf/perf.c:313:11
    #11 0x5570ed731639 in handle_internal_command tools/perf/perf.c:365:8
    #12 0x5570ed7323cd in run_argv tools/perf/perf.c:409:2
    #13 0x5570ed731076 in main tools/perf/perf.c:539:3

Fixes: commit f5a5657 ("perf test: Fix memory leaks in parse-metric test")
Signed-off-by: Ian Rogers <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: [email protected]
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Oct 21, 2020
…vents

It was reported that 'perf stat' crashed when using with armv8_pmu (CPU)
events with the task mode.  As 'perf stat' uses an empty cpu map for
task mode but armv8_pmu has its own cpu mask, it has confused which map
it should use when accessing file descriptors and this causes segfaults:

  (gdb) bt
  #0  0x0000000000603fc8 in perf_evsel__close_fd_cpu (evsel=<optimized out>,
      cpu=<optimized out>) at evsel.c:122
  #1  perf_evsel__close_cpu (evsel=evsel@entry=0x716e950, cpu=7) at evsel.c:156
  #2  0x00000000004d4718 in evlist__close (evlist=0x70a7cb0) at util/evlist.c:1242
  #3  0x0000000000453404 in __run_perf_stat (argc=3, argc@entry=1, argv=0x30,
      argv@entry=0xfffffaea2f90, run_idx=119, run_idx@entry=1701998435)
      at builtin-stat.c:929
  #4  0x0000000000455058 in run_perf_stat (run_idx=1701998435, argv=0xfffffaea2f90,
      argc=1) at builtin-stat.c:947
  #5  cmd_stat (argc=1, argv=0xfffffaea2f90) at builtin-stat.c:2357
  #6  0x00000000004bb888 in run_builtin (p=p@entry=0x9764b8 <commands+288>,
      argc=argc@entry=4, argv=argv@entry=0xfffffaea2f90) at perf.c:312
  #7  0x00000000004bbb54 in handle_internal_command (argc=argc@entry=4,
      argv=argv@entry=0xfffffaea2f90) at perf.c:364
  #8  0x0000000000435378 in run_argv (argcp=<synthetic pointer>,
      argv=<synthetic pointer>) at perf.c:408
  #9  main (argc=4, argv=0xfffffaea2f90) at perf.c:538

To fix this, I simply used the given cpu map unless the evsel actually
is not a system-wide event (like uncore events).

Fixes: 7736627 ("perf stat: Use affinity for closing file descriptors")
Reported-by: Wei Li <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
Tested-by: Barry Song <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Oct 29, 2020
Very sporadically I had test case btrfs/069 from fstests hanging (for
years, it is not a recent regression), with the following traces in
dmesg/syslog:

  [162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started
  [162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0
  [162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished
  [162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds.
  [162513.514318]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.514747] task:btrfs-transacti state:D stack:    0 pid:1356167 ppid:     2 flags:0x00004000
  [162513.514751] Call Trace:
  [162513.514761]  __schedule+0x5ce/0xd00
  [162513.514765]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.514771]  schedule+0x46/0xf0
  [162513.514844]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.514850]  ? finish_wait+0x90/0x90
  [162513.514864]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.514879]  transaction_kthread+0xa4/0x170 [btrfs]
  [162513.514891]  ? btrfs_cleanup_transaction+0x660/0x660 [btrfs]
  [162513.514894]  kthread+0x153/0x170
  [162513.514897]  ? kthread_stop+0x2c0/0x2c0
  [162513.514902]  ret_from_fork+0x22/0x30
  [162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds.
  [162513.515192]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.515680] task:fsstress        state:D stack:    0 pid:1356184 ppid:1356177 flags:0x00004000
  [162513.515682] Call Trace:
  [162513.515688]  __schedule+0x5ce/0xd00
  [162513.515691]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.515697]  schedule+0x46/0xf0
  [162513.515712]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.515716]  ? finish_wait+0x90/0x90
  [162513.515729]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.515743]  btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
  [162513.515753]  btrfs_sync_fs+0x61/0x1c0 [btrfs]
  [162513.515758]  ? __ia32_sys_fdatasync+0x20/0x20
  [162513.515761]  iterate_supers+0x87/0xf0
  [162513.515765]  ksys_sync+0x60/0xb0
  [162513.515768]  __do_sys_sync+0xa/0x10
  [162513.515771]  do_syscall_64+0x33/0x80
  [162513.515774]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.515781] RIP: 0033:0x7f5238f50bd7
  [162513.515782] Code: Bad RIP value.
  [162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
  [162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
  [162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a
  [162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0
  [162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a
  [162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
  [162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds.
  [162513.516064]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.516617] task:fsstress        state:D stack:    0 pid:1356185 ppid:1356177 flags:0x00000000
  [162513.516620] Call Trace:
  [162513.516625]  __schedule+0x5ce/0xd00
  [162513.516628]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.516634]  schedule+0x46/0xf0
  [162513.516647]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.516650]  ? finish_wait+0x90/0x90
  [162513.516662]  start_transaction+0x4d7/0x5f0 [btrfs]
  [162513.516679]  btrfs_setxattr_trans+0x3c/0x100 [btrfs]
  [162513.516686]  __vfs_setxattr+0x66/0x80
  [162513.516691]  __vfs_setxattr_noperm+0x70/0x200
  [162513.516697]  vfs_setxattr+0x6b/0x120
  [162513.516703]  setxattr+0x125/0x240
  [162513.516709]  ? lock_acquire+0xb1/0x480
  [162513.516712]  ? mnt_want_write+0x20/0x50
  [162513.516721]  ? rcu_read_lock_any_held+0x8e/0xb0
  [162513.516723]  ? preempt_count_add+0x49/0xa0
  [162513.516725]  ? __sb_start_write+0x19b/0x290
  [162513.516727]  ? preempt_count_add+0x49/0xa0
  [162513.516732]  path_setxattr+0xba/0xd0
  [162513.516739]  __x64_sys_setxattr+0x27/0x30
  [162513.516741]  do_syscall_64+0x33/0x80
  [162513.516743]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.516745] RIP: 0033:0x7f5238f56d5a
  [162513.516746] Code: Bad RIP value.
  [162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc
  [162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a
  [162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470
  [162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700
  [162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004
  [162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0
  [162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds.
  [162513.517064]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.517763] task:fsstress        state:D stack:    0 pid:1356196 ppid:1356177 flags:0x00004000
  [162513.517780] Call Trace:
  [162513.517786]  __schedule+0x5ce/0xd00
  [162513.517789]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.517796]  schedule+0x46/0xf0
  [162513.517810]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.517814]  ? finish_wait+0x90/0x90
  [162513.517829]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.517845]  btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
  [162513.517857]  btrfs_sync_fs+0x61/0x1c0 [btrfs]
  [162513.517862]  ? __ia32_sys_fdatasync+0x20/0x20
  [162513.517865]  iterate_supers+0x87/0xf0
  [162513.517869]  ksys_sync+0x60/0xb0
  [162513.517872]  __do_sys_sync+0xa/0x10
  [162513.517875]  do_syscall_64+0x33/0x80
  [162513.517878]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.517881] RIP: 0033:0x7f5238f50bd7
  [162513.517883] Code: Bad RIP value.
  [162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
  [162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
  [162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053
  [162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0
  [162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053
  [162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
  [162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds.
  [162513.518298]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.519157] task:fsstress        state:D stack:    0 pid:1356197 ppid:1356177 flags:0x00000000
  [162513.519160] Call Trace:
  [162513.519165]  __schedule+0x5ce/0xd00
  [162513.519168]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.519174]  schedule+0x46/0xf0
  [162513.519190]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.519193]  ? finish_wait+0x90/0x90
  [162513.519206]  start_transaction+0x4d7/0x5f0 [btrfs]
  [162513.519222]  btrfs_create+0x57/0x200 [btrfs]
  [162513.519230]  lookup_open+0x522/0x650
  [162513.519246]  path_openat+0x2b8/0xa50
  [162513.519270]  do_filp_open+0x91/0x100
  [162513.519275]  ? find_held_lock+0x32/0x90
  [162513.519280]  ? lock_acquired+0x33b/0x470
  [162513.519285]  ? do_raw_spin_unlock+0x4b/0xc0
  [162513.519287]  ? _raw_spin_unlock+0x29/0x40
  [162513.519295]  do_sys_openat2+0x20d/0x2d0
  [162513.519300]  do_sys_open+0x44/0x80
  [162513.519304]  do_syscall_64+0x33/0x80
  [162513.519307]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.519309] RIP: 0033:0x7f5238f4a903
  [162513.519310] Code: Bad RIP value.
  [162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
  [162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903
  [162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470
  [162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002
  [162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013
  [162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620
  [162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds.
  [162513.519727]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.520508] task:btrfs           state:D stack:    0 pid:1356211 ppid:1356178 flags:0x00004002
  [162513.520511] Call Trace:
  [162513.520516]  __schedule+0x5ce/0xd00
  [162513.520519]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.520525]  schedule+0x46/0xf0
  [162513.520544]  btrfs_scrub_pause+0x11f/0x180 [btrfs]
  [162513.520548]  ? finish_wait+0x90/0x90
  [162513.520562]  btrfs_commit_transaction+0x45a/0xc30 [btrfs]
  [162513.520574]  ? start_transaction+0xe0/0x5f0 [btrfs]
  [162513.520596]  btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs]
  [162513.520619]  btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs]
  [162513.520639]  btrfs_ioctl+0x2a25/0x36f0 [btrfs]
  [162513.520643]  ? do_sigaction+0xf3/0x240
  [162513.520645]  ? find_held_lock+0x32/0x90
  [162513.520648]  ? do_sigaction+0xf3/0x240
  [162513.520651]  ? lock_acquired+0x33b/0x470
  [162513.520655]  ? _raw_spin_unlock_irq+0x24/0x50
  [162513.520657]  ? lockdep_hardirqs_on+0x7d/0x100
  [162513.520660]  ? _raw_spin_unlock_irq+0x35/0x50
  [162513.520662]  ? do_sigaction+0xf3/0x240
  [162513.520671]  ? __x64_sys_ioctl+0x83/0xb0
  [162513.520672]  __x64_sys_ioctl+0x83/0xb0
  [162513.520677]  do_syscall_64+0x33/0x80
  [162513.520679]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.520681] RIP: 0033:0x7fc3cd307d87
  [162513.520682] Code: Bad RIP value.
  [162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
  [162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87
  [162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003
  [162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  [162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003
  [162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001
  [162513.520703]
		  Showing all locks held in the system:
  [162513.520712] 1 lock held by khungtaskd/54:
  [162513.520713]  #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197
  [162513.520728] 1 lock held by in:imklog/596:
  [162513.520729]  #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60
  [162513.520782] 1 lock held by btrfs-transacti/1356167:
  [162513.520784]  #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs]
  [162513.520798] 1 lock held by btrfs/1356190:
  [162513.520800]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60
  [162513.520805] 1 lock held by fsstress/1356184:
  [162513.520806]  #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
  [162513.520811] 3 locks held by fsstress/1356185:
  [162513.520812]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
  [162513.520815]  #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120
  [162513.520820]  #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
  [162513.520833] 1 lock held by fsstress/1356196:
  [162513.520834]  #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
  [162513.520838] 3 locks held by fsstress/1356197:
  [162513.520839]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
  [162513.520843]  #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50
  [162513.520846]  #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
  [162513.520858] 2 locks held by btrfs/1356211:
  [162513.520859]  #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs]
  [162513.520877]  #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]

This was weird because the stack traces show that a transaction commit,
triggered by a device replace operation, is blocking trying to pause any
running scrubs but there are no stack traces of blocked tasks doing a
scrub.

After poking around with drgn, I noticed there was a scrub task that was
constantly running and blocking for shorts periods of time:

  >>> t = find_task(prog, 1356190)
  >>> prog.stack_trace(t)
  #0  __schedule+0x5ce/0xcfc
  #1  schedule+0x46/0xe4
  #2  schedule_timeout+0x1df/0x475
  #3  btrfs_reada_wait+0xda/0x132
  #4  scrub_stripe+0x2a8/0x112f
  #5  scrub_chunk+0xcd/0x134
  #6  scrub_enumerate_chunks+0x29e/0x5ee
  #7  btrfs_scrub_dev+0x2d5/0x91b
  #8  btrfs_ioctl+0x7f5/0x36e7
  #9  __x64_sys_ioctl+0x83/0xb0
  #10 do_syscall_64+0x33/0x77
  #11 entry_SYSCALL_64+0x7c/0x156

Which corresponds to:

int btrfs_reada_wait(void *handle)
{
    struct reada_control *rc = handle;
    struct btrfs_fs_info *fs_info = rc->fs_info;

    while (atomic_read(&rc->elems)) {
        if (!atomic_read(&fs_info->reada_works_cnt))
            reada_start_machine(fs_info);
        wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0,
                          (HZ + 9) / 10);
    }
(...)

So the counter "rc->elems" was set to 1 and never decreased to 0, causing
the scrub task to loop forever in that function. Then I used the following
script for drgn to check the readahead requests:

  $ cat dump_reada.py
  import sys
  import drgn
  from drgn import NULL, Object, cast, container_of, execscript, \
      reinterpret, sizeof
  from drgn.helpers.linux import *

  mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"

  mnt = None
  for mnt in for_each_mount(prog, dst = mnt_path):
      pass

  if mnt is None:
      sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
      sys.exit(1)

  fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)

  def dump_re(re):
      nzones = re.nzones.value_()
      print(f're at {hex(re.value_())}')
      print(f'\t logical {re.logical.value_()}')
      print(f'\t refcnt {re.refcnt.value_()}')
      print(f'\t nzones {nzones}')
      for i in range(nzones):
          dev = re.zones[i].device
          name = dev.name.str.string_()
          print(f'\t\t dev id {dev.devid.value_()} name {name}')
      print()

  for _, e in radix_tree_for_each(fs_info.reada_tree):
      re = cast('struct reada_extent *', e)
      dump_re(re)

  $ drgn dump_reada.py
  re at 0xffff8f3da9d25ad8
          logical 38928384
          refcnt 1
          nzones 1
                 dev id 0 name b'/dev/sdd'
  $

So there was one readahead extent with a single zone corresponding to the
source device of that last device replace operation logged in dmesg/syslog.
Also the ID of that zone's device was 0 which is a special value set in
the source device of a device replace operation when the operation finishes
(constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()),
confirming again that device /dev/sdd was the source of a device replace
operation.

Normally there should be as many zones in the readahead extent as there are
devices, and I wasn't expecting the extent to be in a block group with a
'single' profile, so I went and confirmed with the following drgn script
that there weren't any single profile block groups:

  $ cat dump_block_groups.py
  import sys
  import drgn
  from drgn import NULL, Object, cast, container_of, execscript, \
      reinterpret, sizeof
  from drgn.helpers.linux import *

  mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"

  mnt = None
  for mnt in for_each_mount(prog, dst = mnt_path):
      pass

  if mnt is None:
      sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
      sys.exit(1)

  fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)

  BTRFS_BLOCK_GROUP_DATA = (1 << 0)
  BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1)
  BTRFS_BLOCK_GROUP_METADATA = (1 << 2)
  BTRFS_BLOCK_GROUP_RAID0 = (1 << 3)
  BTRFS_BLOCK_GROUP_RAID1 = (1 << 4)
  BTRFS_BLOCK_GROUP_DUP = (1 << 5)
  BTRFS_BLOCK_GROUP_RAID10 = (1 << 6)
  BTRFS_BLOCK_GROUP_RAID5 = (1 << 7)
  BTRFS_BLOCK_GROUP_RAID6 = (1 << 8)
  BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9)
  BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10)

  def bg_flags_string(bg):
      flags = bg.flags.value_()
      ret = ''
      if flags & BTRFS_BLOCK_GROUP_DATA:
          ret = 'data'
      if flags & BTRFS_BLOCK_GROUP_METADATA:
          if len(ret) > 0:
              ret += '|'
          ret += 'meta'
      if flags & BTRFS_BLOCK_GROUP_SYSTEM:
          if len(ret) > 0:
              ret += '|'
          ret += 'system'
      if flags & BTRFS_BLOCK_GROUP_RAID0:
          ret += ' raid0'
      elif flags & BTRFS_BLOCK_GROUP_RAID1:
          ret += ' raid1'
      elif flags & BTRFS_BLOCK_GROUP_DUP:
          ret += ' dup'
      elif flags & BTRFS_BLOCK_GROUP_RAID10:
          ret += ' raid10'
      elif flags & BTRFS_BLOCK_GROUP_RAID5:
          ret += ' raid5'
      elif flags & BTRFS_BLOCK_GROUP_RAID6:
          ret += ' raid6'
      elif flags & BTRFS_BLOCK_GROUP_RAID1C3:
          ret += ' raid1c3'
      elif flags & BTRFS_BLOCK_GROUP_RAID1C4:
          ret += ' raid1c4'
      else:
          ret += ' single'

      return ret

  def dump_bg(bg):
      print()
      print(f'block group at {hex(bg.value_())}')
      print(f'\t start {bg.start.value_()} length {bg.length.value_()}')
      print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}')

  bg_root = fs_info.block_group_cache_tree.address_of_()
  for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'):
      dump_bg(bg)

  $ drgn dump_block_groups.py

  block group at 0xffff8f3d673b0400
         start 22020096 length 16777216
         flags 258 - system raid6

  block group at 0xffff8f3d53ddb400
         start 38797312 length 536870912
         flags 260 - meta raid6

  block group at 0xffff8f3d5f4d9c00
         start 575668224 length 2147483648
         flags 257 - data raid6

  block group at 0xffff8f3d08189000
         start 2723151872 length 67108864
         flags 258 - system raid6

  block group at 0xffff8f3db70ff000
         start 2790260736 length 1073741824
         flags 260 - meta raid6

  block group at 0xffff8f3d5f4dd800
         start 3864002560 length 67108864
         flags 258 - system raid6

  block group at 0xffff8f3d67037000
         start 3931111424 length 2147483648
         flags 257 - data raid6
  $

So there were only 2 reasons left for having a readahead extent with a
single zone: reada_find_zone(), called when creating a readahead extent,
returned NULL either because we failed to find the corresponding block
group or because a memory allocation failed. With some additional and
custom tracing I figured out that on every further ocurrence of the
problem the block group had just been deleted when we were looping to
create the zones for the readahead extent (at reada_find_extent()), so we
ended up with only one zone in the readahead extent, corresponding to a
device that ends up getting replaced.

So after figuring that out it became obvious why the hang happens:

1) Task A starts a scrub on any device of the filesystem, except for
   device /dev/sdd;

2) Task B starts a device replace with /dev/sdd as the source device;

3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently
   starting to scrub a stripe from block group X. This call to
   btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add()
   calls reada_add_block(), it passes the logical address of the extent
   tree's root node as its 'logical' argument - a value of 38928384;

4) Task A then enters reada_find_extent(), called from reada_add_block().
   It finds there isn't any existing readahead extent for the logical
   address 38928384, so it proceeds to the path of creating a new one.

   It calls btrfs_map_block() to find out which stripes exist for the block
   group X. On the first iteration of the for loop that iterates over the
   stripes, it finds the stripe for device /dev/sdd, so it creates one
   zone for that device and adds it to the readahead extent. Before getting
   into the second iteration of the loop, the cleanup kthread deletes block
   group X because it was empty. So in the iterations for the remaining
   stripes it does not add more zones to the readahead extent, because the
   calls to reada_find_zone() returned NULL because they couldn't find
   block group X anymore.

   As a result the new readahead extent has a single zone, corresponding to
   the device /dev/sdd;

4) Before task A returns to btrfs_reada_add() and queues the readahead job
   for the readahead work queue, task B finishes the device replace and at
   btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new
   device /dev/sdg;

5) Task A returns to reada_add_block(), which increments the counter
   "->elems" of the reada_control structure allocated at btrfs_reada_add().

   Then it returns back to btrfs_reada_add() and calls
   reada_start_machine(). This queues a job in the readahead work queue to
   run the function reada_start_machine_worker(), which calls
   __reada_start_machine().

   At __reada_start_machine() we take the device list mutex and for each
   device found in the current device list, we call
   reada_start_machine_dev() to start the readahead work. However at this
   point the device /dev/sdd was already freed and is not in the device
   list anymore.

   This means the corresponding readahead for the extent at 38928384 is
   never started, and therefore the "->elems" counter of the reada_control
   structure allocated at btrfs_reada_add() never goes down to 0, causing
   the call to btrfs_reada_wait(), done by the scrub task, to wait forever.

Note that the readahead request can be made either after the device replace
started or before it started, however in pratice it is very unlikely that a
device replace is able to start after a readahead request is made and is
able to complete before the readahead request completes - maybe only on a
very small and nearly empty filesystem.

This hang however is not the only problem we can have with readahead and
device removals. When the readahead extent has other zones other than the
one corresponding to the device that is being removed (either by a device
replace or a device remove operation), we risk having a use-after-free on
the device when dropping the last reference of the readahead extent.

For example if we create a readahead extent with two zones, one for the
device /dev/sdd and one for the device /dev/sde:

1) Before the readahead worker starts, the device /dev/sdd is removed,
   and the corresponding btrfs_device structure is freed. However the
   readahead extent still has the zone pointing to the device structure;

2) When the readahead worker starts, it only finds device /dev/sde in the
   current device list of the filesystem;

3) It starts the readahead work, at reada_start_machine_dev(), using the
   device /dev/sde;

4) Then when it finishes reading the extent from device /dev/sde, it calls
   __readahead_hook() which ends up dropping the last reference on the
   readahead extent through the last call to reada_extent_put();

5) At reada_extent_put() it iterates over each zone of the readahead extent
   and attempts to delete an element from the device's 'reada_extents'
   radix tree, resulting in a use-after-free, as the device pointer of the
   zone for /dev/sdd is now stale. We can also access the device after
   dropping the last reference of a zone, through reada_zone_release(),
   also called by reada_extent_put().

And a device remove suffers the same problem, however since it shrinks the
device size down to zero before removing the device, it is very unlikely to
still have readahead requests not completed by the time we free the device,
the only possibility is if the device has a very little space allocated.

While the hang problem is exclusive to scrub, since it is currently the
only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free
problem affects any path that triggers readhead, which includes
btree_readahead_hook() and __readahead_hook() (a readahead worker can
trigger readahed for the children of a node) for example - any path that
ends up calling reada_add_block() can trigger the use-after-free after a
device is removed.

So fix this by waiting for any readahead requests for a device to complete
before removing a device, ensuring that while waiting for existing ones no
new ones can be made.

This problem has been around for a very long time - the readahead code was
added in 2011, device remove exists since 2008 and device replace was
introduced in 2013, hard to pick a specific commit for a git Fixes tag.

CC: [email protected] # 4.4+
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
digetx pushed a commit that referenced this issue Nov 16, 2020
Ido Schimmel says:

====================
mlxsw: Preparations for nexthop objects support - part 1/2

This patch set contains small and non-functional changes aimed at making
it easier to support nexthop objects in mlxsw. Follow up patches can be
found here [1].

Patches #1-#4 add a type field to the nexthop group struct instead of
the existing protocol field. This will be used later on to add a nexthop
object type, which can contain both IPv4 and IPv6 nexthops.

Patches #5-#7 move the IPv4 FIB info pointer (i.e., 'struct fib_info')
from the nexthop group struct to the route. The pointer will not be
available when the nexthop group is a nexthop object, but it needs to be
accessible to routes regardless.

Patch #8 is the biggest change, but it is an entirely cosmetic change
and should therefore be easy to review. The motivation and the change
itself are explained in detail in the commit message.

Patches #9-#12 perform small changes so that two functions that are
currently split between IPv4 and IPv6 could be consolidated in patches

Patch #15 removes an outdated comment.

[1] https://github.com/idosch/linux/tree/submit/nexthop_objects
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
digetx pushed a commit that referenced this issue Dec 16, 2020
Ido Schimmel says:

====================
mlxsw: Introduce initial XM router support

This patch set implements initial eXtended Mezzanine (XM) router
support.

The XM is an external device connected to the Spectrum-{2,3} ASICs using
dedicated Ethernet ports. Its purpose is to increase the number of
routes that can be offloaded to hardware. This is achieved by having the
ASIC act as a cache that refers cache misses to the XM where the FIB is
stored and LPM lookup is performed.

Future patch sets will add more sophisticated cache flushing and
selftests that utilize cache counters on the ASIC, which we plan to
expose via devlink-metric [1].

Patch set overview:

Patches #1-#2 add registers to insert/remove routes to/from the XM and
to enable/disable it. Patch #3 utilizes these registers in order to
implement XM-specific router low-level operations.

Patches #4-#5 query from firmware the availability of the XM and the
local ports that are used to connect the ASIC to the XM, so that netdevs
will not be created for them.

Patches #6-#8 initialize the XM by configuring its cache parameters.

Patch #9-#10 implement cache management, so that LPM lookup will be
correctly cached in the ASIC.

Patches #11-#13 implement cache flushing, so that routes
insertions/removals to/from the XM will flush the affected entries in
the cache.

Patch #14 configures the ASIC to allocate half of its memory for the
cache, so that room will be left for other entries (e.g., FDBs,
neighbours).

Patch #15 starts using the XM for IPv4 route offload, when available.

[1] https://lore.kernel.org/netdev/[email protected]/
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
digetx pushed a commit that referenced this issue Jan 12, 2021
We had kernel panic, it is caused by unload module and last
close confirmation.

call trace:
[1196029.743127]  free_sess+0x15/0x50 [rtrs_client]
[1196029.743128]  rtrs_clt_close+0x4c/0x70 [rtrs_client]
[1196029.743129]  ? rnbd_clt_unmap_device+0x1b0/0x1b0 [rnbd_client]
[1196029.743130]  close_rtrs+0x25/0x50 [rnbd_client]
[1196029.743131]  rnbd_client_exit+0x93/0xb99 [rnbd_client]
[1196029.743132]  __x64_sys_delete_module+0x190/0x260

And in the crashdump confirmation kworker is also running.
PID: 6943   TASK: ffff9e2ac8098000  CPU: 4   COMMAND: "kworker/4:2"
 #0 [ffffb206cf337c30] __schedule at ffffffff9f93f891
 #1 [ffffb206cf337cc8] schedule at ffffffff9f93fe98
 #2 [ffffb206cf337cd0] schedule_timeout at ffffffff9f943938
 #3 [ffffb206cf337d50] wait_for_completion at ffffffff9f9410a7
 #4 [ffffb206cf337da0] __flush_work at ffffffff9f08ce0e
 #5 [ffffb206cf337e20] rtrs_clt_close_conns at ffffffffc0d5f668 [rtrs_client]
 #6 [ffffb206cf337e48] rtrs_clt_close at ffffffffc0d5f801 [rtrs_client]
 #7 [ffffb206cf337e68] close_rtrs at ffffffffc0d26255 [rnbd_client]
 #8 [ffffb206cf337e78] free_sess at ffffffffc0d262ad [rnbd_client]
 #9 [ffffb206cf337e88] rnbd_clt_put_dev at ffffffffc0d266a7 [rnbd_client]

The problem is both code path try to close same session, which lead to
panic.

To fix it, just skip the sess if the refcount already drop to 0.

Fixes: f7a7a5c ("block/rnbd: client: main functionality")
Signed-off-by: Jack Wang <[email protected]>
Reviewed-by: Gioh Kim <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
digetx pushed a commit that referenced this issue Jan 27, 2021
The bit that indicates if the device supports 160MHZ
is bit #9. The macro checks bit #8.

Fix IWL_SUBDEVICE_NO_160 macro to use the correct bit.

Signed-off-by: Matti Gottlieb <[email protected]>
Fixes: d6f2134 ("iwlwifi: add mac/rf types and 160MHz to the device tables")
Signed-off-by: Luca Coelho <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
Link: https://lore.kernel.org/r/iwlwifi.20210122144849.bddbf9b57a75.I16e09e2b1404b16bfff70852a5a654aa468579e2@changeid
digetx pushed a commit that referenced this issue Feb 24, 2021
The ubsan reported the following error.  It was because sample's raw
data missed u32 padding at the end.  So it broke the alignment of the
array after it.

The raw data contains an u32 size prefix so the data size should have
an u32 padding after 8-byte aligned data.

27: Sample parsing  :util/synthetic-events.c:1539:4:
  runtime error: store to misaligned address 0x62100006b9bc for type
  '__u64' (aka 'unsigned long long'), which requires 8 byte alignment
0x62100006b9bc: note: pointer points here
  00 00 00 00 ff ff ff ff  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
              ^
    #0 0x561532a9fc96 in perf_event__synthesize_sample util/synthetic-events.c:1539:13
    #1 0x5615327f4a4f in do_test tests/sample-parsing.c:284:8
    #2 0x5615327f3f50 in test__sample_parsing tests/sample-parsing.c:381:9
    #3 0x56153279d3a1 in run_test tests/builtin-test.c:424:9
    #4 0x56153279c836 in test_and_print tests/builtin-test.c:454:9
    #5 0x56153279b7eb in __cmd_test tests/builtin-test.c:675:4
    #6 0x56153279abf0 in cmd_test tests/builtin-test.c:821:9
    #7 0x56153264e796 in run_builtin perf.c:312:11
    #8 0x56153264cf03 in handle_internal_command perf.c:364:8
    #9 0x56153264e47d in run_argv perf.c:408:2
    #10 0x56153264c9a9 in main perf.c:538:3
    #11 0x7f137ab6fbbc in __libc_start_main (/lib64/libc.so.6+0x38bbc)
    #12 0x561532596828 in _start ...

SUMMARY: UndefinedBehaviorSanitizer: misaligned-pointer-use
 util/synthetic-events.c:1539:4 in

Fixes: 045f8cd ("perf tests: Add a sample parsing test")
Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Mar 29, 2021
I got several memory leak reports from Asan with a simple command.  It
was because VDSO is not released due to the refcount.  Like in
__dsos_addnew_id(), it should put the refcount after adding to the list.

  $ perf record true
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.030 MB perf.data (10 samples) ]

  =================================================================
  ==692599==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 439 byte(s) in 1 object(s) allocated from:
    #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x559bce4aa8ee in dso__new_id util/dso.c:1256
    #2 0x559bce59245a in __machine__addnew_vdso util/vdso.c:132
    #3 0x559bce59245a in machine__findnew_vdso util/vdso.c:347
    #4 0x559bce50826c in map__new util/map.c:175
    #5 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787
    #6 0x559bce512f6b in machines__deliver_event util/session.c:1481
    #7 0x559bce515107 in perf_session__deliver_event util/session.c:1551
    #8 0x559bce51d4d2 in do_flush util/ordered-events.c:244
    #9 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323
    #10 0x559bce519bea in __perf_session__process_events util/session.c:2268
    #11 0x559bce519bea in perf_session__process_events util/session.c:2297
    #12 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017
    #13 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234
    #14 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026
    #15 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858
    #16 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #17 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #18 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #19 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #20 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308

  Indirect leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x559bce520907 in nsinfo__copy util/namespaces.c:169
    #2 0x559bce50821b in map__new util/map.c:168
    #3 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787
    #4 0x559bce512f6b in machines__deliver_event util/session.c:1481
    #5 0x559bce515107 in perf_session__deliver_event util/session.c:1551
    #6 0x559bce51d4d2 in do_flush util/ordered-events.c:244
    #7 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323
    #8 0x559bce519bea in __perf_session__process_events util/session.c:2268
    #9 0x559bce519bea in perf_session__process_events util/session.c:2297
    #10 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017
    #11 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234
    #12 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026
    #13 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858
    #14 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #15 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #16 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #17 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #18 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s).

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Apr 1, 2021
The following deadlock is detected:

truncate -> setattr path is waiting for pending direct IO to be done (
inode->i_dio_count become zero) with inode->i_rwsem held (down_write).

PID: 14827  TASK: ffff881686a9af80  CPU: 20  COMMAND: "ora_p005_hrltd9"
#0 [ffffc9000bcf3c08] __schedule at ffffffff818667cc
#1 [ffffc9000bcf3ca0] schedule at ffffffff81866de6
#2 [ffffc9000bcf3cb8] inode_dio_wait at ffffffff812a2d04
#3 [ffffc9000bcf3d28] ocfs2_setattr at ffffffffc05f322e [ocfs2]
#4 [ffffc9000bcf3e18] notify_change at ffffffff812a5a09
#5 [ffffc9000bcf3e60] do_truncate at ffffffff812808f5
#6 [ffffc9000bcf3ed8] do_sys_ftruncate.constprop.18 at ffffffff81280cf2
#7 [ffffc9000bcf3f18] sys_ftruncate at ffffffff81280d8e
#8 [ffffc9000bcf3f28] do_syscall_64 at ffffffff81003949
#9 [ffffc9000bcf3f50] entry_SYSCALL_64_after_hwframe at ffffffff81a001ad

dio completion path is going to complete one direct IO (decrement
inode->i_dio_count), but before that it hang at locking inode->i_rwsem.

 #0 [ffffc90009b47b40] __schedule+700 at ffffffff818667cc
 #1 [ffffc90009b47bd8] schedule+54 at ffffffff81866de6
 #2 [ffffc90009b47bf0] rwsem_down_write_failed+536 at ffffffff8186aa28
 #3 [ffffc90009b47c88] call_rwsem_down_write_failed+23 at ffffffff8185a1b7
 #4 [ffffc90009b47cd0] down_write+45 at ffffffff81869c9d
 #5 [ffffc90009b47ce8] ocfs2_dio_end_io_write+180 at ffffffffc05d5444 [ocfs2]
 #6 [ffffc90009b47dd8] ocfs2_dio_end_io+85 at ffffffffc05d5a85 [ocfs2]
 #7 [ffffc90009b47e18] dio_complete+140 at ffffffff812c873c
 #8 [ffffc90009b47e50] dio_aio_complete_work+25 at ffffffff812c89f9
 #9 [ffffc90009b47e60] process_one_work+361 at ffffffff810b1889
#10 [ffffc90009b47ea8] worker_thread+77 at ffffffff810b233d
#11 [ffffc90009b47f08] kthread+261 at ffffffff810b7fd5
#12 [ffffc90009b47f50] ret_from_fork+62 at ffffffff81a0035e

Thus above forms ABBA deadlock. The same deadlock was mentioned in
upstream commit 28f5a8a. well, it seems
that that commit just removed cluster lock (the victim of above dead
lock) from the ABBA deadlock party.

End-user visible effects:
Process hang in truncate -> ocfs2_setattr path and other processes hang at
ocfs2_dio_end_io_write path.

This is to fix the deadlock its self. It removes inode_lock() call from dio
completion path to remove the deadlock and add ip_alloc_sem lock in setattr
path to synchronize the inode modifications.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Wengang Wang <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Joseph Qi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
digetx pushed a commit that referenced this issue Apr 10, 2021
Split mddev_find into a simple mddev_find that just finds an existing
mddev by the unit number, and a more complicated mddev_find that deals
with find or allocating a mddev.

This turns out to fix this bug reported by Zhao Heming.

----------------------------- snip ------------------------------
commit d337482 ("md: make devices disappear when they are no longer
needed.") introduced protection between mddev creating & removing. The
md_open shouldn't create mddev when all_mddevs list doesn't contain
mddev. With currently code logic, there will be very easy to trigger
soft lockup in non-preempt env.

*** env ***
kvm-qemu VM 2C1G with 2 iscsi luns
kernel should be non-preempt

*** script ***

about trigger 1 time with 10 tests

`1  node1="15sp3-mdcluster1"
2  node2="15sp3-mdcluster2"
3
4  mdadm -Ss
5  ssh ${node2} "mdadm -Ss"
6  wipefs -a /dev/sda /dev/sdb
7  mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda \
   /dev/sdb --assume-clean
8
9  for i in {1..100}; do
10    echo ==== $i ====;
11
12    echo "test  ...."
13    ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb"
14    sleep 1
15
16    echo "clean  ....."
17    ssh ${node2} "mdadm -Ss"
18 done
`
I use mdcluster env to trigger soft lockup, but it isn't mdcluster
speical bug. To stop md array in mdcluster env will do more jobs than
non-cluster array, which will leave enough time/gap to allow kernel to
run md_open.

*** stack ***

`ID: 2831   TASK: ffff8dd7223b5040  CPU: 0   COMMAND: "mdadm"
 #0 [ffffa15d00a13b90] __schedule at ffffffffb8f1935f
 #1 [ffffa15d00a13ba8] exact_lock at ffffffffb8a4a66d
 #2 [ffffa15d00a13bb0] kobj_lookup at ffffffffb8c62fe3
 #3 [ffffa15d00a13c28] __blkdev_get at ffffffffb89273b9
 #4 [ffffa15d00a13c98] blkdev_get at ffffffffb8927964
 #5 [ffffa15d00a13cb0] do_dentry_open at ffffffffb88dc4b4
 #6 [ffffa15d00a13ce0] path_openat at ffffffffb88f0ccc
 #7 [ffffa15d00a13db8] do_filp_open at ffffffffb88f32bb
 #8 [ffffa15d00a13ee0] do_sys_open at ffffffffb88ddc7d
 #9 [ffffa15d00a13f38] do_syscall_64 at ffffffffb86053cb ffffffffb900008c

or:
[  884.226509]  mddev_put+0x1c/0xe0 [md_mod]
[  884.226515]  md_open+0x3c/0xe0 [md_mod]
[  884.226518]  __blkdev_get+0x30d/0x710
[  884.226520]  ? bd_acquire+0xd0/0xd0
[  884.226522]  blkdev_get+0x14/0x30
[  884.226524]  do_dentry_open+0x204/0x3a0
[  884.226531]  path_openat+0x2fc/0x1520
[  884.226534]  ? seq_printf+0x4e/0x70
[  884.226536]  do_filp_open+0x9b/0x110
[  884.226542]  ? md_release+0x20/0x20 [md_mod]
[  884.226543]  ? seq_read+0x1d8/0x3e0
[  884.226545]  ? kmem_cache_alloc+0x18a/0x270
[  884.226547]  ? do_sys_open+0x1bd/0x260
[  884.226548]  do_sys_open+0x1bd/0x260
[  884.226551]  do_syscall_64+0x5b/0x1e0
[  884.226554]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
`
*** rootcause ***

"mdadm -A" (or other array assemble commands) will start a daemon "mdadm
--monitor" by default. When "mdadm -Ss" is running, the stop action will
wakeup "mdadm --monitor". The "--monitor" daemon will immediately get
info from /proc/mdstat. This time mddev in kernel still exist, so
/proc/mdstat still show md device, which makes "mdadm --monitor" to open
/dev/md0.

The previously "mdadm -Ss" is removing action, the "mdadm --monitor"
open action will trigger md_open which is creating action. Racing is
happening.

`<thread 1>: "mdadm -Ss"
md_release
  mddev_put deletes mddev from all_mddevs
  queue_work for mddev_delayed_delete
  at this time, "/dev/md0" is still available for opening

<thread 2>: "mdadm --monitor ..."
md_open
 + mddev_find can't find mddev of /dev/md0, and create a new mddev and
 |    return.
 + trigger "if (mddev->gendisk != bdev->bd_disk)" and return
      -ERESTARTSYS.
`
In non-preempt kernel, <thread 2> is occupying on current CPU. and
mddev_delayed_delete which was created in <thread 1> also can't be
schedule.

In preempt kernel, it can also trigger above racing. But kernel doesn't
allow one thread running on a CPU all the time. after <thread 2> running
some time, the later "mdadm -A" (refer above script line 13) will call
md_alloc to alloc a new gendisk for mddev. it will break md_open
statement "if (mddev->gendisk != bdev->bd_disk)" and return 0 to caller,
the soft lockup is broken.
------------------------------ snip ------------------------------

Cc: [email protected]
Fixes: d337482 ("md: make devices disappear when they are no longer needed.")
Reported-by: Heming Zhao <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Song Liu <[email protected]>
digetx pushed a commit that referenced this issue Apr 27, 2021
In bnxt_rx_pkt(), the RX buffers are expected to complete in order.
If the RX consumer index indicates an out of order buffer completion,
it means we are hitting a hardware bug and the driver will abort all
remaining RX packets and reset the RX ring.  The RX consumer index
that we pass to bnxt_discard_rx() is not correct.  We should be
passing the current index (tmp_raw_cons) instead of the old index
(raw_cons).  This bug can cause us to be at the wrong index when
trying to abort the next RX packet.  It can crash like this:

 #0 [ffff9bbcdf5c39a8] machine_kexec at ffffffff9b05e007
 #1 [ffff9bbcdf5c3a00] __crash_kexec at ffffffff9b111232
 #2 [ffff9bbcdf5c3ad0] panic at ffffffff9b07d61e
 #3 [ffff9bbcdf5c3b50] oops_end at ffffffff9b030978
 #4 [ffff9bbcdf5c3b78] no_context at ffffffff9b06aaf0
 #5 [ffff9bbcdf5c3bd8] __bad_area_nosemaphore at ffffffff9b06ae2e
 #6 [ffff9bbcdf5c3c28] bad_area_nosemaphore at ffffffff9b06af24
 #7 [ffff9bbcdf5c3c38] __do_page_fault at ffffffff9b06b67e
 #8 [ffff9bbcdf5c3cb0] do_page_fault at ffffffff9b06bb12
 #9 [ffff9bbcdf5c3ce0] page_fault at ffffffff9bc015c5
    [exception RIP: bnxt_rx_pkt+237]
    RIP: ffffffffc0259cdd  RSP: ffff9bbcdf5c3d98  RFLAGS: 00010213
    RAX: 000000005dd8097f  RBX: ffff9ba4cb11b7e0  RCX: ffffa923cf6e9000
    RDX: 0000000000000fff  RSI: 0000000000000627  RDI: 0000000000001000
    RBP: ffff9bbcdf5c3e60   R8: 0000000000420003   R9: 000000000000020d
    R10: ffffa923cf6ec138  R11: ffff9bbcdf5c3e83  R12: ffff9ba4d6f928c0
    R13: ffff9ba4cac28080  R14: ffff9ba4cb11b7f0  R15: ffff9ba4d5a30000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018

Fixes: a1b0e4e ("bnxt_en: Improve RX consumer index validity check.")
Reviewed-by: Pavan Chebbi <[email protected]>
Reviewed-by: Andy Gospodarek <[email protected]>
Signed-off-by: Michael Chan <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
digetx pushed a commit that referenced this issue May 20, 2021
Ido Schimmel says:

====================
mlxsw: Various updates

This patchset contains various updates to the mlxsw driver and related
selftests.

Patches #1-#5 contain various updates to mlxsw selftests. The most
significant change is the conversion of the DCB selftests to use the new
iproute2 DCB support.

Patches #6-#9 contain mostly trivial changes to the driver itself. No
user facing changes.

Patches #10-#11 remove support for SwitchX-2 and SwitchIB ASICs that did
not see any updates in the last 4-5 years and will not see any in the
future. See individual commit messages for detailed explanation as to
why it is OK to remove these drivers from the kernel.
====================

Signed-off-by: David S. Miller <[email protected]>
digetx pushed a commit that referenced this issue Jun 3, 2021
…nect

It's possible to trigger NULL pointer dereference by local unprivileged
user, when calling getsockname() after failed bind() (e.g. the bind
fails because LLCP_SAP_MAX used as SAP):

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  CPU: 1 PID: 426 Comm: llcp_sock_getna Not tainted 5.13.0-rc2-next-20210521+ #9
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1 04/01/2014
  Call Trace:
   llcp_sock_getname+0xb1/0xe0
   __sys_getpeername+0x95/0xc0
   ? lockdep_hardirqs_on_prepare+0xd5/0x180
   ? syscall_enter_from_user_mode+0x1c/0x40
   __x64_sys_getpeername+0x11/0x20
   do_syscall_64+0x36/0x70
   entry_SYSCALL_64_after_hwframe+0x44/0xae

This can be reproduced with Syzkaller C repro (bind followed by
getpeername):
https://syzkaller.appspot.com/x/repro.c?x=14def446e00000

Cc: <[email protected]>
Fixes: d646960 ("NFC: Initial LLCP support")
Reported-by: [email protected]
Reported-by: butt3rflyh4ck <[email protected]>
Signed-off-by: Krzysztof Kozlowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
digetx pushed a commit that referenced this issue Jun 9, 2021
ASan reported a memory leak caused by info_linear not being deallocated.

The info_linear was allocated during in perf_event__synthesize_one_bpf_prog().

This patch adds the corresponding free() when bpf_prog_info_node
is freed in perf_env__purge_bpf().

  $ sudo ./perf record -- sleep 5
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.025 MB perf.data (8 samples) ]

  =================================================================
  ==297735==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 7688 byte(s) in 19 object(s) allocated from:
      #0 0x4f420f in malloc (/home/user/linux/tools/perf/perf+0x4f420f)
      #1 0xc06a74 in bpf_program__get_prog_info_linear /home/user/linux/tools/lib/bpf/libbpf.c:11113:16
      #2 0xb426fe in perf_event__synthesize_one_bpf_prog /home/user/linux/tools/perf/util/bpf-event.c:191:16
      #3 0xb42008 in perf_event__synthesize_bpf_events /home/user/linux/tools/perf/util/bpf-event.c:410:9
      #4 0x594596 in record__synthesize /home/user/linux/tools/perf/builtin-record.c:1490:8
      #5 0x58c9ac in __cmd_record /home/user/linux/tools/perf/builtin-record.c:1798:8
      #6 0x58990b in cmd_record /home/user/linux/tools/perf/builtin-record.c:2901:8
      #7 0x7b2a20 in run_builtin /home/user/linux/tools/perf/perf.c:313:11
      #8 0x7b12ff in handle_internal_command /home/user/linux/tools/perf/perf.c:365:8
      #9 0x7b2583 in run_argv /home/user/linux/tools/perf/perf.c:409:2
      #10 0x7b0d79 in main /home/user/linux/tools/perf/perf.c:539:3
      #11 0x7fa357ef6b74 in __libc_start_main /usr/src/debug/glibc-2.33-8.fc34.x86_64/csu/../csu/libc-start.c:332:16

Signed-off-by: Riccardo Mancini <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Fastabend <[email protected]>
Cc: KP Singh <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Martin KaFai Lau <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Yonghong Song <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Jun 9, 2021
Our syzkaller trigger the "BUG_ON(!list_empty(&inode->i_wb_list))" in
clear_inode:

[  292.016156] ------------[ cut here ]------------
[  292.017144] kernel BUG at fs/inode.c:519!
[  292.017860] Internal error: Oops - BUG: 0 [#1] SMP
[  292.018741] Dumping ftrace buffer:
[  292.019577]    (ftrace buffer empty)
[  292.020430] Modules linked in:
[  292.021748] Process syz-executor.0 (pid: 249, stack limit =
0x00000000a12409d7)
[  292.023719] CPU: 1 PID: 249 Comm: syz-executor.0 Not tainted 4.19.95
[  292.025206] Hardware name: linux,dummy-virt (DT)
[  292.026176] pstate: 80000005 (Nzcv daif -PAN -UAO)
[  292.027244] pc : clear_inode+0x280/0x2a8
[  292.028045] lr : clear_inode+0x280/0x2a8
[  292.028877] sp : ffff8003366c7950
[  292.029582] x29: ffff8003366c7950 x28: 0000000000000000
[  292.030570] x27: ffff80032b5f4708 x26: ffff80032b5f4678
[  292.031863] x25: ffff80036ae6b300 x24: ffff8003689254d0
[  292.032902] x23: ffff80036ae69d80 x22: 0000000000033cc8
[  292.033928] x21: 0000000000000000 x20: ffff80032b5f47a0
[  292.034941] x19: ffff80032b5f4678 x18: 0000000000000000
[  292.035958] x17: 0000000000000000 x16: 0000000000000000
[  292.037102] x15: 0000000000000000 x14: 0000000000000000
[  292.038103] x13: 0000000000000004 x12: 0000000000000000
[  292.039137] x11: 1ffff00066cd8f52 x10: 1ffff00066cd8ec8
[  292.040216] x9 : dfff200000000000 x8 : ffff10006ac1e86a
[  292.041432] x7 : dfff200000000000 x6 : ffff100066cd8f1e
[  292.042516] x5 : dfff200000000000 x4 : ffff80032b5f47a0
[  292.043525] x3 : ffff200008000000 x2 : ffff200009867000
[  292.044560] x1 : ffff8003366bb000 x0 : 0000000000000000
[  292.045569] Call trace:
[  292.046083]  clear_inode+0x280/0x2a8
[  292.046828]  ext4_clear_inode+0x38/0xe8
[  292.047593]  ext4_free_inode+0x130/0xc68
[  292.048383]  ext4_evict_inode+0xb20/0xcb8
[  292.049162]  evict+0x1a8/0x3c0
[  292.049761]  iput+0x344/0x460
[  292.050350]  do_unlinkat+0x260/0x410
[  292.051042]  __arm64_sys_unlinkat+0x6c/0xc0
[  292.051846]  el0_svc_common+0xdc/0x3b0
[  292.052570]  el0_svc_handler+0xf8/0x160
[  292.053303]  el0_svc+0x10/0x218
[  292.053908] Code: 9413f4a9 d503201f f90017b6 97f4d5b1 (d4210000)
[  292.055471] ---[ end trace 01b339dd07795f8d ]---
[  292.056443] Kernel panic - not syncing: Fatal exception
[  292.057488] SMP: stopping secondary CPUs
[  292.058419] Dumping ftrace buffer:
[  292.059078]    (ftrace buffer empty)
[  292.059756] Kernel Offset: disabled
[  292.060443] CPU features: 0x10,a1006000
[  292.061195] Memory Limit: none
[  292.061794] Rebooting in 86400 seconds..

Crash of this problem show that someone call __munlock_pagevec to clear
page LRU without lock_page.

 #0 [ffff80035f02f4c0] __switch_to at ffff20000808d020
 #1 [ffff80035f02f4f0] __schedule at ffff20000985102c
 #2 [ffff80035f02f5e0] schedule at ffff200009851d1c
 #3 [ffff80035f02f600] io_schedule at ffff2000098525c0
 #4 [ffff80035f02f620] __lock_page at ffff20000842d2d4
 #5 [ffff80035f02f710] __munlock_pagevec at ffff2000084c4600
 #6 [ffff80035f02f870] munlock_vma_pages_range at ffff2000084c5928
 #7 [ffff80035f02fa60] do_munmap at ffff2000084cbdf4
 #8 [ffff80035f02faf0] mmap_region at ffff2000084ce20c
 #9 [ffff80035f02fb90] do_mmap at ffff2000084cf018

So memory_failure will call identify_page_state without
wait_on_page_writeback.  And after truncate_error_page clear the mapping
of this page.  end_page_writeback won't call sb_clear_inode_writeback to
clear inode->i_wb_list.  That will trigger BUG_ON in clear_inode!

Fix it by checking PageWriteback too to help determine should we skip
wait_on_page_writeback.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 0bc1f8b ("hwpoison: fix the handling path of the victimized page frame that belong to non-LRU")
Signed-off-by: yangerkun <[email protected]>
Acked-by: Naoya Horiguchi <[email protected]>
Cc: Jan Kara <[email protected]>
Cc: Theodore Ts'o <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Yu Kuai <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
digetx pushed a commit that referenced this issue Sep 20, 2021
It's later supposed to be either a correct address or NULL. Without the
initialization, it may contain an undefined value which results in the
following segmentation fault:

  # perf top --sort comm -g --ignore-callees=do_idle

terminates with:

  #0  0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6
  #1  0x00007ffff55e3802 in strdup () from /lib64/libc.so.6
  #2  0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489
  #3  hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564
  #4  0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420,
      sample_self=sample_self@entry=true) at util/hist.c:657
  #5  0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0,
      sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288
  #6  0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38)
      at util/hist.c:1056
  #7  iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056
  #8  0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0)
      at util/hist.c:1231
  #9  0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0)
      at builtin-top.c:842
  #10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202
  #11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244
  #12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323
  #13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339
  #14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341
  #15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339
  #16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114
  #17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0
  #18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6

If you look at the frame #2, the code is:

488	 if (he->srcline) {
489          he->srcline = strdup(he->srcline);
490          if (he->srcline == NULL)
491              goto err_rawdata;
492	 }

If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish),
it gets strdupped and strdupping a rubbish random string causes the problem.

Also, if you look at the commit 1fb7d06, it adds the srcline property
into the struct, but not initializing it everywhere needed.

Committer notes:

Now I see, when using --ignore-callees=do_idle we end up here at line
2189 in add_callchain_ip():

2181         if (al.sym != NULL) {
2182                 if (perf_hpp_list.parent && !*parent &&
2183                     symbol__match_regex(al.sym, &parent_regex))
2184                         *parent = al.sym;
2185                 else if (have_ignore_callees && root_al &&
2186                   symbol__match_regex(al.sym, &ignore_callees_regex)) {
2187                         /* Treat this symbol as the root,
2188                            forgetting its callees. */
2189                         *root_al = al;
2190                         callchain_cursor_reset(cursor);
2191                 }
2192         }

And the al that doesn't have the ->srcline field initialized will be
copied to the root_al, so then, back to:

1211 int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
1212                          int max_stack_depth, void *arg)
1213 {
1214         int err, err2;
1215         struct map *alm = NULL;
1216
1217         if (al)
1218                 alm = map__get(al->map);
1219
1220         err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent,
1221                                         iter->evsel, al, max_stack_depth);
1222         if (err) {
1223                 map__put(alm);
1224                 return err;
1225         }
1226
1227         err = iter->ops->prepare_entry(iter, al);
1228         if (err)
1229                 goto out;
1230
1231         err = iter->ops->add_single_entry(iter, al);
1232         if (err)
1233                 goto out;
1234

That al at line 1221 is what hist_entry_iter__add() (called from
sample__resolve_callchain()) saw as 'root_al', and then:

        iter->ops->add_single_entry(iter, al);

will go on with al->srcline with a bogus value, I'll add the above
sequence to the cset and apply, thanks!

Signed-off-by: Michael Petlan <[email protected]>
CC: Milian Wolff <[email protected]>
Cc: Jiri Olsa <[email protected]>
Fixes: 1fb7d06 ("perf report Use srcline from callchain for hist entries")
Link: https //lore.kernel.org/r/[email protected]
Reported-by: Juri Lelli <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Sep 20, 2021
FD uses xyarray__entry that may return NULL if an index is out of
bounds. If NULL is returned then a segv happens as FD unconditionally
dereferences the pointer. This was happening in a case of with perf
iostat as shown below. The fix is to make FD an "int*" rather than an
int and handle the NULL case as either invalid input or a closed fd.

  $ sudo gdb --args perf stat --iostat  list
  ...
  Breakpoint 1, perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50
  50      {
  (gdb) bt
   #0  perf_evsel__alloc_fd (evsel=0x5555560951a0, ncpus=1, nthreads=1) at evsel.c:50
   #1  0x000055555585c188 in evsel__open_cpu (evsel=0x5555560951a0, cpus=0x555556093410,
      threads=0x555556086fb0, start_cpu=0, end_cpu=1) at util/evsel.c:1792
   #2  0x000055555585cfb2 in evsel__open (evsel=0x5555560951a0, cpus=0x0, threads=0x555556086fb0)
      at util/evsel.c:2045
   #3  0x000055555585d0db in evsel__open_per_thread (evsel=0x5555560951a0, threads=0x555556086fb0)
      at util/evsel.c:2065
   #4  0x00005555558ece64 in create_perf_stat_counter (evsel=0x5555560951a0,
      config=0x555555c34700 <stat_config>, target=0x555555c2f1c0 <target>, cpu=0) at util/stat.c:590
   #5  0x000055555578e927 in __run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0)
      at builtin-stat.c:833
   #6  0x000055555578f3c6 in run_perf_stat (argc=1, argv=0x7fffffffe4a0, run_idx=0)
      at builtin-stat.c:1048
   #7  0x0000555555792ee5 in cmd_stat (argc=1, argv=0x7fffffffe4a0) at builtin-stat.c:2534
   #8  0x0000555555835ed3 in run_builtin (p=0x555555c3f540 <commands+288>, argc=3,
      argv=0x7fffffffe4a0) at perf.c:313
   #9  0x0000555555836154 in handle_internal_command (argc=3, argv=0x7fffffffe4a0) at perf.c:365
   #10 0x000055555583629f in run_argv (argcp=0x7fffffffe2ec, argv=0x7fffffffe2e0) at perf.c:409
   #11 0x0000555555836692 in main (argc=3, argv=0x7fffffffe4a0) at perf.c:539
  ...
  (gdb) c
  Continuing.
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (uncore_iio_0/event=0x83,umask=0x04,ch_mask=0xF,fc_mask=0x07/).
  /bin/dmesg | grep -i perf may provide additional information.

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555559b03ea in perf_evsel__close_fd_cpu (evsel=0x5555560951a0, cpu=1) at evsel.c:166
  166                     if (FD(evsel, cpu, thread) >= 0)

v3. fixes a bug in perf_evsel__run_ioctl where the sense of a branch was
    backward.

Signed-off-by: Ian Rogers <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Sep 26, 2021
Host crashes when pci_enable_atomic_ops_to_root() is called for VFs with
virtual buses. The virtual buses added to SR-IOV have bus->self set to NULL
and host crashes due to this.

  PID: 4481   TASK: ffff89c6941b0000  CPU: 53  COMMAND: "bash"
  ...
   #3 [ffff9a9481713808] oops_end at ffffffffb9025cd6
   #4 [ffff9a9481713828] page_fault_oops at ffffffffb906e417
   #5 [ffff9a9481713888] exc_page_fault at ffffffffb9a0ad14
   #6 [ffff9a94817138b0] asm_exc_page_fault at ffffffffb9c00ace
      [exception RIP: pcie_capability_read_dword+28]
      RIP: ffffffffb952fd5c  RSP: ffff9a9481713960  RFLAGS: 00010246
      RAX: 0000000000000001  RBX: ffff89c6b1096000  RCX: 0000000000000000
      RDX: ffff9a9481713990  RSI: 0000000000000024  RDI: 0000000000000000
      RBP: 0000000000000080   R8: 0000000000000008   R9: ffff89c64341a2f8
      R10: 0000000000000002  R11: 0000000000000000  R12: ffff89c648bab000
      R13: 0000000000000000  R14: 0000000000000000  R15: ffff89c648bab0c8
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #7 [ffff9a9481713988] pci_enable_atomic_ops_to_root at ffffffffb95359a6
   #8 [ffff9a94817139c0] bnxt_qplib_determine_atomics at ffffffffc08c1a33 [bnxt_re]
   #9 [ffff9a94817139d0] bnxt_re_dev_init at ffffffffc08ba2d1 [bnxt_re]

Per PCIe r5.0, sec 9.3.5.10, the AtomicOp Requester Enable bit in Device
Control 2 is reserved for VFs.  The PF value applies to all associated PFs.

Return -EINVAL if pci_enable_atomic_ops_to_root() is called for a VF.

Link: https://lore.kernel.org/r/[email protected]
Fixes: 35f5ace ("RDMA/bnxt_re: Enable global atomic ops if platform supports")
Fixes: 430a236 ("PCI: Add pci_enable_atomic_ops_to_root()")
Signed-off-by: Selvin Xavier <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Andy Gospodarek <[email protected]>
digetx pushed a commit that referenced this issue Sep 27, 2021
Ido Schimmel says:

====================
mlxsw: Add support for IP-in-IP with IPv6 underlay

Currently, mlxsw only supports IP-in-IP with IPv4 underlay. Traffic
routed through 'gre' netdevs is encapsulated with IPv4 and GRE headers.
Similarly, incoming IPv4 GRE packets are decapsulated and routed in the
overlay VRF (which can be the same as the underlay VRF).

This patchset adds support for IPv6 underlay using the 'ip6gre' netdev.
Due to architectural differences between Spectrum-1 and later ASICs,
this functionality is only supported on Spectrum-2 onwards (the software
data path is used for Spectrum-1).

Patchset overview:

Patches #1-#5 are preparations.

Patches #6-#9 add and extend required device registers.

Patches #10-#14 gradually add IPv6 underlay support.

A follow-up patchset will add net/forwarding/ selftests.
====================

Signed-off-by: David S. Miller <[email protected]>
digetx pushed a commit that referenced this issue Sep 29, 2021
If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic

 *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0);

will become undefined behavior because nbits modulo BITS_PER_BYTE is 0, and we
subtract one from that making a large number that is then shifted more than the
number of bits that fit into an unsigned long.

UBSAN reports this problem:

 UBSAN: shift-out-of-bounds in drivers/nvmem/core.c:1386:8
 shift exponent 64 is too large for 64-bit type 'unsigned long'
 CPU: 6 PID: 7 Comm: kworker/u16:0 Not tainted 5.15.0-rc3+ #9
 Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
 Workqueue: events_unbound deferred_probe_work_func
 Call trace:
  dump_backtrace+0x0/0x170
  show_stack+0x24/0x30
  dump_stack_lvl+0x64/0x7c
  dump_stack+0x18/0x38
  ubsan_epilogue+0x10/0x54
  __ubsan_handle_shift_out_of_bounds+0x180/0x194
  __nvmem_cell_read+0x1ec/0x21c
  nvmem_cell_read+0x58/0x94
  nvmem_cell_read_variable_common+0x4c/0xb0
  nvmem_cell_read_variable_le_u32+0x40/0x100
  a6xx_gpu_init+0x170/0x2f4
  adreno_bind+0x174/0x284
  component_bind_all+0xf0/0x264
  msm_drm_bind+0x1d8/0x7a0
  try_to_bring_up_master+0x164/0x1ac
  __component_add+0xbc/0x13c
  component_add+0x20/0x2c
  dp_display_probe+0x340/0x384
  platform_probe+0xc0/0x100
  really_probe+0x110/0x304
  __driver_probe_device+0xb8/0x120
  driver_probe_device+0x4c/0xfc
  __device_attach_driver+0xb0/0x128
  bus_for_each_drv+0x90/0xdc
  __device_attach+0xc8/0x174
  device_initial_probe+0x20/0x2c
  bus_probe_device+0x40/0xa4
  deferred_probe_work_func+0x7c/0xb8
  process_one_work+0x128/0x21c
  process_scheduled_works+0x40/0x54
  worker_thread+0x1ec/0x2a8
  kthread+0x138/0x158
  ret_from_fork+0x10/0x20

Fix it by making sure there are any bits to mask out.

Cc: Douglas Anderson <[email protected]>
Fixes: 69aba79 ("nvmem: Add a simple NVMEM framework for consumers")
Cc: [email protected]
Signed-off-by: Stephen Boyd <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
digetx pushed a commit that referenced this issue Sep 29, 2021
Andrii Nakryiko says:

====================

Implement opt-in stricter BPF program section name (SEC()) handling logic. For
a lot of supported ELF section names, enforce exact section name match with no
arbitrary characters added at the end. See patch #9 for more details.

To allow this, patches #2 through #4 clean up and preventively fix selftests,
normalizing existing SEC() usage across multiple selftests. While at it, those
patches also reduce the amount of remaining bpf_object__find_program_by_title()
uses, which should be completely removed soon, given it's an API with
ambiguous semantics and will be deprecated and eventually removed in libbpf 1.0.

Patch #1 also introduces SEC("tc") as an alias for SEC("classifier"). "tc" is
a better and less misleading name, so patch #3 replaces all classifier* uses
with nice and short SEC("tc").

Last patch is also fixing "sk_lookup/" definition to not require and not allow
extra "/blah" parts after it, which serve no meaning.

All the other patches are gradual internal libbpf changes to:
  - allow this optional strict logic for ELF section name handling;
  - allow new use case (for now for "struct_ops", but that could be extended
    to, say, freplace definitions), in which it can be used stand-alone to
    specify just type (SEC("struct_ops")), or also accept extra parameters
    which can be utilized by libbpf to either get more data or double-check
    valid use (e.g., SEC("struct_ops/dctcp_init") to specify desired
    struct_ops operation that is supposed to be implemented);
  - get libbpf's internal logic ready to allow other libraries and
    applications to specify their custom handlers for ELF section name for BPF
    programs. All the pieces are in place, the only thing preventing making
    this as public libbpf API is reliance on internal type for specifying BPF
    program load attributes. The work is planned to revamp related low-level
    libbpf APIs, at which point it will be possible to just re-use such new
    types for coordination between libbpf and custom handlers.

These changes are a part of libbpf 1.0 effort ([0]). They are also intended to
be applied on top of the previous preparatory series [1], so currently CI will
be failing to apply them to bpf-next until that patch set is landed. Once it
is landed, kernel-patches daemon will automatically retest this patch set.

  [0] https://github.com/libbpf/libbpf/wiki/Libbpf:-the-road-to-v1.0#stricter-and-more-uniform-bpf-program-section-name-sec-handling
  [1] https://patchwork.kernel.org/project/netdevbpf/list/?series=547675&state=*

v3->v4:
  - replace SEC("classifier*") with SEC("tc") (Daniel);
v2->v3:
  - applied acks, addressed most feedback, added comments to new flags (Dave);
v1->v2:
  - rebase onto latest bpf-next and resolve merge conflicts w/ Dave's changes.
====================

Signed-off-by: Alexei Starovoitov <[email protected]>
digetx pushed a commit that referenced this issue Oct 22, 2021
Attempting to defragment a Btrfs file containing a transparent huge page
immediately deadlocks with the following stack trace:

  #0  context_switch (kernel/sched/core.c:4940:2)
  #1  __schedule (kernel/sched/core.c:6287:8)
  #2  schedule (kernel/sched/core.c:6366:3)
  #3  io_schedule (kernel/sched/core.c:8389:2)
  #4  wait_on_page_bit_common (mm/filemap.c:1356:4)
  #5  __lock_page (mm/filemap.c:1648:2)
  #6  lock_page (./include/linux/pagemap.h:625:3)
  #7  pagecache_get_page (mm/filemap.c:1910:4)
  #8  find_or_create_page (./include/linux/pagemap.h:420:9)
  #9  defrag_prepare_one_page (fs/btrfs/ioctl.c:1068:9)
  #10 defrag_one_range (fs/btrfs/ioctl.c:1326:14)
  #11 defrag_one_cluster (fs/btrfs/ioctl.c:1421:9)
  #12 btrfs_defrag_file (fs/btrfs/ioctl.c:1523:9)
  #13 btrfs_ioctl_defrag (fs/btrfs/ioctl.c:3117:9)
  #14 btrfs_ioctl (fs/btrfs/ioctl.c:4872:10)
  #15 vfs_ioctl (fs/ioctl.c:51:10)
  #16 __do_sys_ioctl (fs/ioctl.c:874:11)
  #17 __se_sys_ioctl (fs/ioctl.c:860:1)
  #18 __x64_sys_ioctl (fs/ioctl.c:860:1)
  #19 do_syscall_x64 (arch/x86/entry/common.c:50:14)
  #20 do_syscall_64 (arch/x86/entry/common.c:80:7)
  #21 entry_SYSCALL_64+0x7c/0x15b (arch/x86/entry/entry_64.S:113)

A huge page is represented by a compound page, which consists of a
struct page for each PAGE_SIZE page within the huge page. The first
struct page is the "head page", and the remaining are "tail pages".

Defragmentation attempts to lock each page in the range. However,
lock_page() on a tail page actually locks the corresponding head page.
So, if defragmentation tries to lock more than one struct page in a
compound page, it tries to lock the same head page twice and deadlocks
with itself.

Ideally, we should be able to defragment transparent huge pages.
However, THP for filesystems is currently read-only, so a lot of code is
not ready to use huge pages for I/O. For now, let's just return
ETXTBUSY.

This can be reproduced with the following on a kernel with
CONFIG_READ_ONLY_THP_FOR_FS=y:

  $ cat create_thp_file.c
  #include <fcntl.h>
  #include <stdbool.h>
  #include <stdio.h>
  #include <stdint.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <sys/mman.h>

  static const char zeroes[1024 * 1024];
  static const size_t FILE_SIZE = 2 * 1024 * 1024;

  int main(int argc, char **argv)
  {
          if (argc != 2) {
                  fprintf(stderr, "usage: %s PATH\n", argv[0]);
                  return EXIT_FAILURE;
          }
          int fd = creat(argv[1], 0777);
          if (fd == -1) {
                  perror("creat");
                  return EXIT_FAILURE;
          }
          size_t written = 0;
          while (written < FILE_SIZE) {
                  ssize_t ret = write(fd, zeroes,
                                      sizeof(zeroes) < FILE_SIZE - written ?
                                      sizeof(zeroes) : FILE_SIZE - written);
                  if (ret < 0) {
                          perror("write");
                          return EXIT_FAILURE;
                  }
                  written += ret;
          }
          close(fd);
          fd = open(argv[1], O_RDONLY);
          if (fd == -1) {
                  perror("open");
                  return EXIT_FAILURE;
          }

          /*
           * Reserve some address space so that we can align the file mapping to
           * the huge page size.
           */
          void *placeholder_map = mmap(NULL, FILE_SIZE * 2, PROT_NONE,
                                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
          if (placeholder_map == MAP_FAILED) {
                  perror("mmap (placeholder)");
                  return EXIT_FAILURE;
          }

          void *aligned_address =
                  (void *)(((uintptr_t)placeholder_map + FILE_SIZE - 1) & ~(FILE_SIZE - 1));

          void *map = mmap(aligned_address, FILE_SIZE, PROT_READ | PROT_EXEC,
                           MAP_SHARED | MAP_FIXED, fd, 0);
          if (map == MAP_FAILED) {
                  perror("mmap");
                  return EXIT_FAILURE;
          }
          if (madvise(map, FILE_SIZE, MADV_HUGEPAGE) < 0) {
                  perror("madvise");
                  return EXIT_FAILURE;
          }

          char *line = NULL;
          size_t line_capacity = 0;
          FILE *smaps_file = fopen("/proc/self/smaps", "r");
          if (!smaps_file) {
                  perror("fopen");
                  return EXIT_FAILURE;
          }
          for (;;) {
                  for (size_t off = 0; off < FILE_SIZE; off += 4096)
                          ((volatile char *)map)[off];

                  ssize_t ret;
                  bool this_mapping = false;
                  while ((ret = getline(&line, &line_capacity, smaps_file)) > 0) {
                          unsigned long start, end, huge;
                          if (sscanf(line, "%lx-%lx", &start, &end) == 2) {
                                  this_mapping = (start <= (uintptr_t)map &&
                                                  (uintptr_t)map < end);
                          } else if (this_mapping &&
                                     sscanf(line, "FilePmdMapped: %ld", &huge) == 1 &&
                                     huge > 0) {
                                  return EXIT_SUCCESS;
                          }
                  }

                  sleep(6);
                  rewind(smaps_file);
                  fflush(smaps_file);
          }
  }
  $ ./create_thp_file huge
  $ btrfs fi defrag -czstd ./huge

Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Omar Sandoval <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
digetx pushed a commit that referenced this issue Oct 27, 2021
Ido Schimmel says:

====================
mlxsw: Support multiple RIF MAC prefixes

Currently, mlxsw enforces that all the netdevs used as router interfaces
(RIFs) have the same MAC prefix (e.g., same 38 MSBs in Spectrum-1).
Otherwise, an error is returned to user space with extack. This patchset
relaxes the limitation through the use of RIF MAC profiles.

A RIF MAC profile is a hardware entity that represents a particular MAC
prefix which multiple RIFs can reference. Therefore, the number of
possible MAC prefixes is no longer one, but the number of profiles
supported by the device.

The ability to change the MAC of a particular netdev is useful, for
example, for users who use the netdev to connect to an upstream provider
that performs MAC filtering. Currently, such users are either forced to
negotiate with the provider or change the MAC address of all other
netdevs so that they share the same prefix.

Patchset overview:

Patches #1-#3 are preparations.

Patch #4 adds actual support for RIF MAC profiles.

Patch #5 exposes RIF MAC profiles as a devlink resource, so that user
space has visibility into the maximum number of profiles and current
occupancy. Useful for debugging and testing (next 3 patches).

Patches #6-#8 add both scale and functional tests.

Patch #9 removes tests that validated the previous limitation. It is now
covered by patch #6 for devices that support a single profile.
====================

Signed-off-by: David S. Miller <[email protected]>
digetx pushed a commit that referenced this issue Oct 27, 2021
Attempting to defragment a Btrfs file containing a transparent huge page
immediately deadlocks with the following stack trace:

  #0  context_switch (kernel/sched/core.c:4940:2)
  #1  __schedule (kernel/sched/core.c:6287:8)
  #2  schedule (kernel/sched/core.c:6366:3)
  #3  io_schedule (kernel/sched/core.c:8389:2)
  #4  wait_on_page_bit_common (mm/filemap.c:1356:4)
  #5  __lock_page (mm/filemap.c:1648:2)
  #6  lock_page (./include/linux/pagemap.h:625:3)
  #7  pagecache_get_page (mm/filemap.c:1910:4)
  #8  find_or_create_page (./include/linux/pagemap.h:420:9)
  #9  defrag_prepare_one_page (fs/btrfs/ioctl.c:1068:9)
  #10 defrag_one_range (fs/btrfs/ioctl.c:1326:14)
  #11 defrag_one_cluster (fs/btrfs/ioctl.c:1421:9)
  #12 btrfs_defrag_file (fs/btrfs/ioctl.c:1523:9)
  #13 btrfs_ioctl_defrag (fs/btrfs/ioctl.c:3117:9)
  #14 btrfs_ioctl (fs/btrfs/ioctl.c:4872:10)
  #15 vfs_ioctl (fs/ioctl.c:51:10)
  #16 __do_sys_ioctl (fs/ioctl.c:874:11)
  #17 __se_sys_ioctl (fs/ioctl.c:860:1)
  #18 __x64_sys_ioctl (fs/ioctl.c:860:1)
  #19 do_syscall_x64 (arch/x86/entry/common.c:50:14)
  #20 do_syscall_64 (arch/x86/entry/common.c:80:7)
  #21 entry_SYSCALL_64+0x7c/0x15b (arch/x86/entry/entry_64.S:113)

A huge page is represented by a compound page, which consists of a
struct page for each PAGE_SIZE page within the huge page. The first
struct page is the "head page", and the remaining are "tail pages".

Defragmentation attempts to lock each page in the range. However,
lock_page() on a tail page actually locks the corresponding head page.
So, if defragmentation tries to lock more than one struct page in a
compound page, it tries to lock the same head page twice and deadlocks
with itself.

Ideally, we should be able to defragment transparent huge pages.
However, THP for filesystems is currently read-only, so a lot of code is
not ready to use huge pages for I/O. For now, let's just return
ETXTBUSY.

This can be reproduced with the following on a kernel with
CONFIG_READ_ONLY_THP_FOR_FS=y:

  $ cat create_thp_file.c
  #include <fcntl.h>
  #include <stdbool.h>
  #include <stdio.h>
  #include <stdint.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <sys/mman.h>

  static const char zeroes[1024 * 1024];
  static const size_t FILE_SIZE = 2 * 1024 * 1024;

  int main(int argc, char **argv)
  {
          if (argc != 2) {
                  fprintf(stderr, "usage: %s PATH\n", argv[0]);
                  return EXIT_FAILURE;
          }
          int fd = creat(argv[1], 0777);
          if (fd == -1) {
                  perror("creat");
                  return EXIT_FAILURE;
          }
          size_t written = 0;
          while (written < FILE_SIZE) {
                  ssize_t ret = write(fd, zeroes,
                                      sizeof(zeroes) < FILE_SIZE - written ?
                                      sizeof(zeroes) : FILE_SIZE - written);
                  if (ret < 0) {
                          perror("write");
                          return EXIT_FAILURE;
                  }
                  written += ret;
          }
          close(fd);
          fd = open(argv[1], O_RDONLY);
          if (fd == -1) {
                  perror("open");
                  return EXIT_FAILURE;
          }

          /*
           * Reserve some address space so that we can align the file mapping to
           * the huge page size.
           */
          void *placeholder_map = mmap(NULL, FILE_SIZE * 2, PROT_NONE,
                                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
          if (placeholder_map == MAP_FAILED) {
                  perror("mmap (placeholder)");
                  return EXIT_FAILURE;
          }

          void *aligned_address =
                  (void *)(((uintptr_t)placeholder_map + FILE_SIZE - 1) & ~(FILE_SIZE - 1));

          void *map = mmap(aligned_address, FILE_SIZE, PROT_READ | PROT_EXEC,
                           MAP_SHARED | MAP_FIXED, fd, 0);
          if (map == MAP_FAILED) {
                  perror("mmap");
                  return EXIT_FAILURE;
          }
          if (madvise(map, FILE_SIZE, MADV_HUGEPAGE) < 0) {
                  perror("madvise");
                  return EXIT_FAILURE;
          }

          char *line = NULL;
          size_t line_capacity = 0;
          FILE *smaps_file = fopen("/proc/self/smaps", "r");
          if (!smaps_file) {
                  perror("fopen");
                  return EXIT_FAILURE;
          }
          for (;;) {
                  for (size_t off = 0; off < FILE_SIZE; off += 4096)
                          ((volatile char *)map)[off];

                  ssize_t ret;
                  bool this_mapping = false;
                  while ((ret = getline(&line, &line_capacity, smaps_file)) > 0) {
                          unsigned long start, end, huge;
                          if (sscanf(line, "%lx-%lx", &start, &end) == 2) {
                                  this_mapping = (start <= (uintptr_t)map &&
                                                  (uintptr_t)map < end);
                          } else if (this_mapping &&
                                     sscanf(line, "FilePmdMapped: %ld", &huge) == 1 &&
                                     huge > 0) {
                                  return EXIT_SUCCESS;
                          }
                  }

                  sleep(6);
                  rewind(smaps_file);
                  fflush(smaps_file);
          }
  }
  $ ./create_thp_file huge
  $ btrfs fi defrag -czstd ./huge

Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Omar Sandoval <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
digetx pushed a commit that referenced this issue Nov 5, 2021
Host crashes when pci_enable_atomic_ops_to_root() is called for VFs with
virtual buses. The virtual buses added to SR-IOV have bus->self set to NULL
and host crashes due to this.

  PID: 4481   TASK: ffff89c6941b0000  CPU: 53  COMMAND: "bash"
  ...
   #3 [ffff9a9481713808] oops_end at ffffffffb9025cd6
   #4 [ffff9a9481713828] page_fault_oops at ffffffffb906e417
   #5 [ffff9a9481713888] exc_page_fault at ffffffffb9a0ad14
   #6 [ffff9a94817138b0] asm_exc_page_fault at ffffffffb9c00ace
      [exception RIP: pcie_capability_read_dword+28]
      RIP: ffffffffb952fd5c  RSP: ffff9a9481713960  RFLAGS: 00010246
      RAX: 0000000000000001  RBX: ffff89c6b1096000  RCX: 0000000000000000
      RDX: ffff9a9481713990  RSI: 0000000000000024  RDI: 0000000000000000
      RBP: 0000000000000080   R8: 0000000000000008   R9: ffff89c64341a2f8
      R10: 0000000000000002  R11: 0000000000000000  R12: ffff89c648bab000
      R13: 0000000000000000  R14: 0000000000000000  R15: ffff89c648bab0c8
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #7 [ffff9a9481713988] pci_enable_atomic_ops_to_root at ffffffffb95359a6
   #8 [ffff9a94817139c0] bnxt_qplib_determine_atomics at ffffffffc08c1a33 [bnxt_re]
   #9 [ffff9a94817139d0] bnxt_re_dev_init at ffffffffc08ba2d1 [bnxt_re]

Per PCIe r5.0, sec 9.3.5.10, the AtomicOp Requester Enable bit in Device
Control 2 is reserved for VFs.  The PF value applies to all associated VFs.

Return -EINVAL if pci_enable_atomic_ops_to_root() is called for a VF.

Link: https://lore.kernel.org/r/[email protected]
Fixes: 35f5ace ("RDMA/bnxt_re: Enable global atomic ops if platform supports")
Fixes: 430a236 ("PCI: Add pci_enable_atomic_ops_to_root()")
Signed-off-by: Selvin Xavier <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Andy Gospodarek <[email protected]>
digetx pushed a commit that referenced this issue Nov 16, 2021
…gy()

When testing cpu online and offline, warning happened like this:

[  146.746743] WARNING: CPU: 92 PID: 974 at kernel/sched/topology.c:2215 build_sched_domains+0x81c/0x11b0
[  146.749988] CPU: 92 PID: 974 Comm: kworker/92:2 Not tainted 5.15.0 #9
[  146.750402] Hardware name: Huawei TaiShan 2280 V2/BC82AMDDA, BIOS 1.79 08/21/2021
[  146.751213] Workqueue: events cpuset_hotplug_workfn
[  146.751629] pstate: 00400009 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  146.752048] pc : build_sched_domains+0x81c/0x11b0
[  146.752461] lr : build_sched_domains+0x414/0x11b0
[  146.752860] sp : ffff800040a83a80
[  146.753247] x29: ffff800040a83a80 x28: ffff20801f13a980 x27: ffff20800448ae00
[  146.753644] x26: ffff800012a858e8 x25: ffff800012ea48c0 x24: 0000000000000000
[  146.754039] x23: ffff800010ab7d60 x22: ffff800012f03758 x21: 000000000000005f
[  146.754427] x20: 000000000000005c x19: ffff004080012840 x18: ffffffffffffffff
[  146.754814] x17: 3661613030303230 x16: 30303078303a3239 x15: ffff800011f92b48
[  146.755197] x14: ffff20be3f95cef6 x13: 2e6e69616d6f642d x12: 6465686373204c4c
[  146.755578] x11: ffff20bf7fc83a00 x10: 0000000000000040 x9 : 0000000000000000
[  146.755957] x8 : 0000000000000002 x7 : ffffffffe0000000 x6 : 0000000000000002
[  146.756334] x5 : 0000000090000000 x4 : 00000000f0000000 x3 : 0000000000000001
[  146.756705] x2 : 0000000000000080 x1 : ffff800012f03860 x0 : 0000000000000001
[  146.757070] Call trace:
[  146.757421]  build_sched_domains+0x81c/0x11b0
[  146.757771]  partition_sched_domains_locked+0x57c/0x978
[  146.758118]  rebuild_sched_domains_locked+0x44c/0x7f0
[  146.758460]  rebuild_sched_domains+0x2c/0x48
[  146.758791]  cpuset_hotplug_workfn+0x3fc/0x888
[  146.759114]  process_one_work+0x1f4/0x480
[  146.759429]  worker_thread+0x48/0x460
[  146.759734]  kthread+0x158/0x168
[  146.760030]  ret_from_fork+0x10/0x20
[  146.760318] ---[ end trace 82c44aad6900e81a ]---

For some architectures like risc-v and arm64 which use common code
clear_cpu_topology() in shutting down CPUx, When CONFIG_SCHED_CLUSTER
is set, cluster_sibling in cpu_topology of each sibling adjacent
to CPUx is missed clearing, this causes checking failed in
topology_span_sane() and rebuilding topology failure at end when CPU online.

Different sibling's cluster_sibling in cpu_topology[] when CPU92 offline
(CPU 92, 93, 94, 95 are in one cluster):

Before revision:
CPU                 [92]      [93]      [94]      [95]
cluster_sibling     [92]     [92-95]   [92-95]   [92-95]

After revision:
CPU                 [92]      [93]      [94]      [95]
cluster_sibling     [92]     [93-95]   [93-95]   [93-95]

Signed-off-by: Wang ShaoBo <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Dietmar Eggemann <[email protected]>
Acked-by: Barry Song <[email protected]>
Tested-by: Dietmar Eggemann <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
digetx pushed a commit that referenced this issue Nov 16, 2021
The exit function fixes a memory leak with the src field as detected by
leak sanitizer. An example of which is:

Indirect leak of 25133184 byte(s) in 207 object(s) allocated from:
    #0 0x7f199ecfe987 in __interceptor_calloc libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x55defe638224 in annotated_source__alloc_histograms util/annotate.c:803
    #2 0x55defe6397e4 in symbol__hists util/annotate.c:952
    #3 0x55defe639908 in symbol__inc_addr_samples util/annotate.c:968
    #4 0x55defe63aa29 in hist_entry__inc_addr_samples util/annotate.c:1119
    #5 0x55defe499a79 in hist_iter__report_callback tools/perf/builtin-report.c:182
    #6 0x55defe7a859d in hist_entry_iter__add util/hist.c:1236
    #7 0x55defe49aa63 in process_sample_event tools/perf/builtin-report.c:315
    #8 0x55defe731bc8 in evlist__deliver_sample util/session.c:1473
    #9 0x55defe731e38 in machines__deliver_event util/session.c:1510
    #10 0x55defe732a23 in perf_session__deliver_event util/session.c:1590
    #11 0x55defe72951e in ordered_events__deliver_event util/session.c:183
    #12 0x55defe740082 in do_flush util/ordered-events.c:244
    #13 0x55defe7407cb in __ordered_events__flush util/ordered-events.c:323
    #14 0x55defe740a61 in ordered_events__flush util/ordered-events.c:341
    #15 0x55defe73837f in __perf_session__process_events util/session.c:2390
    #16 0x55defe7385ff in perf_session__process_events util/session.c:2420
    ...

Signed-off-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Martin Liška <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
digetx pushed a commit that referenced this issue Jan 16, 2022
If the key is already present then free the key used for lookup.

Found with:
$ perf stat -M IO_Read_BW /bin/true

==1749112==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 32 byte(s) in 4 object(s) allocated from:
    #0 0x7f6f6fa7d7cf in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x55acecd9d7a6 in check_per_pkg util/stat.c:343
    #2 0x55acecd9d9c5 in process_counter_values util/stat.c:365
    #3 0x55acecd9e0ab in process_counter_maps util/stat.c:421
    #4 0x55acecd9e292 in perf_stat_process_counter util/stat.c:443
    #5 0x55aceca8553e in read_counters ./tools/perf/builtin-stat.c:470
    #6 0x55aceca88fe3 in __run_perf_stat ./tools/perf/builtin-stat.c:1023
    #7 0x55aceca89146 in run_perf_stat ./tools/perf/builtin-stat.c:1048
    #8 0x55aceca90858 in cmd_stat ./tools/perf/builtin-stat.c:2555
    #9 0x55acecc05fa5 in run_builtin ./tools/perf/perf.c:313
    #10 0x55acecc064fe in handle_internal_command ./tools/perf/perf.c:365
    #11 0x55acecc068bb in run_argv ./tools/perf/perf.c:409
    #12 0x55acecc070aa in main ./tools/perf/perf.c:539

Reviewed-by: James Clark <[email protected]>
Signed-off-by: Ian Rogers <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Garry <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mathieu Poirier <[email protected]>
Cc: Mike Leach <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Paul Clarke <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Suzuki Poulouse <[email protected]>
Cc: Vineet Singh <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Feb 6, 2022
[ Upstream commit f1797e4 ]

module_alloc() first tries to allocate module text within 24 bits direct
jump from kernel text, and tries a wider allocation if first one fails.

When first allocation fails the following is observed in kernel logs:

  vmap allocation for size 2400256 failed: use vmalloc=<size> to increase size
  systemd-udevd: vmalloc error: size 2395133, vm_struct allocation failed, mode:0xcc0(GFP_KERNEL), nodemask=(null)
  CPU: 0 PID: 127 Comm: systemd-udevd Tainted: G        W         5.15.5-gentoo-PowerMacG4 grate-driver#9
  Call Trace:
  [e2a53a50] [c0ba0048] dump_stack_lvl+0x80/0xb0 (unreliable)
  [e2a53a70] [c0540128] warn_alloc+0x11c/0x2b4
  [e2a53b50] [c0531be8] __vmalloc_node_range+0xd8/0x64c
  [e2a53c10] [c00338c0] module_alloc+0xa0/0xac
  [e2a53c40] [c027a368] load_module+0x2ae0/0x8148
  [e2a53e30] [c027fc78] sys_finit_module+0xfc/0x130
  [e2a53f30] [c0035098] ret_from_syscall+0x0/0x28
  ...

Add __GFP_NOWARN flag to first allocation so that no warning appears
when it fails.

Reported-by: Erhard Furtner <[email protected]>
Fixes: 2ec13df ("powerpc/modules: Load modules closer to kernel text")
Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/93c9b84d6ec76aaf7b4f03468e22433a6d308674.1638267035.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Feb 6, 2022
[ Upstream commit af11dee ]

================================================================================
UBSAN: shift-out-of-bounds in arch/powerpc/mm/kasan/book3s_32.c:22:23
shift exponent -1 is negative
CPU: 0 PID: 0 Comm: swapper Not tainted 5.15.5-gentoo-PowerMacG4 grate-driver#9
Call Trace:
[c214be60] [c0ba0048] dump_stack_lvl+0x80/0xb0 (unreliable)
[c214be80] [c0b99288] ubsan_epilogue+0x10/0x5c
[c214be90] [c0b98fe0] __ubsan_handle_shift_out_of_bounds+0x94/0x138
[c214bf00] [c1c0f010] kasan_init_region+0xd8/0x26c
[c214bf30] [c1c0ed84] kasan_init+0xc0/0x198
[c214bf70] [c1c08024] setup_arch+0x18/0x54c
[c214bfc0] [c1c037f0] start_kernel+0x90/0x33c
[c214bff0] [00003610] 0x3610
================================================================================

This happens when the directly mapped memory is a power of 2.

Fix it by checking the shift and set the result to 0 when shift is -1

Fixes: 7974c47 ("powerpc/32s: Implement dedicated kasan_init_region()")
Reported-by: Erhard Furtner <[email protected]>
Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215169
Link: https://lore.kernel.org/r/15cbc3439d4ad988b225e2119ec99502a5cc6ad3.1638261744.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Feb 6, 2022
[ Upstream commit df1f679 ]

KeyWest i2c @0xf8001003 irq 42 /uni-n@f8000000/i2c@f8001000
BUG: key c2d00cbc has not been registered!
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:4801 lockdep_init_map_type+0x4c0/0xb4c
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.15.5-gentoo-PowerMacG4 grate-driver#9
NIP:  c01a9428 LR: c01a9428 CTR: 00000000
REGS: e1033cf0 TRAP: 0700   Not tainted  (5.15.5-gentoo-PowerMacG4)
MSR:  00029032 <EE,ME,IR,DR,RI>  CR: 24002002  XER: 00000000

GPR00: c01a9428 e1033db0 c2d1cf20 00000016 00000004 00000001 c01c0630 e1033a73
GPR08: 00000000 00000000 00000000 e1033db0 24002004 00000000 f8729377 00000003
GPR16: c1829a9c 00000000 18305357 c1416fc0 c1416f80 c006ac60 c2d00ca8 c1416f00
GPR24: 00000000 c21586f0 c2160000 00000000 c2d00cbc c2170000 c216e1a0 c2160000
NIP [c01a9428] lockdep_init_map_type+0x4c0/0xb4c
LR [c01a9428] lockdep_init_map_type+0x4c0/0xb4c
Call Trace:
[e1033db0] [c01a9428] lockdep_init_map_type+0x4c0/0xb4c (unreliable)
[e1033df0] [c1c177b8] kw_i2c_add+0x334/0x424
[e1033e20] [c1c18294] pmac_i2c_init+0x9ec/0xa9c
[e1033e80] [c1c1a790] smp_core99_probe+0xbc/0x35c
[e1033eb0] [c1c03cb0] kernel_init_freeable+0x190/0x5a4
[e1033f10] [c000946c] kernel_init+0x28/0x154
[e1033f30] [c0035148] ret_from_kernel_thread+0x14/0x1c

Add missing lockdep_register_key()

Reported-by: Erhard Furtner <[email protected]>
Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/69e4f55565bb45ebb0843977801b245af0c666fe.1638264741.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <[email protected]>
jonasschwoebel pushed a commit to Open-Surface-RT/grate-linux that referenced this issue Oct 21, 2022
Patch series "mm: COW fixes part 1: fix the COW security issue for THP and swap", v3.

This series attempts to optimize and streamline the COW logic for ordinary
anon pages and THP anon pages, fixing two remaining instances of
CVE-2020-29374 in do_swap_page() and do_huge_pmd_wp_page(): information
can leak from a parent process to a child process via anonymous pages
shared during fork().

This issue, including other related COW issues, has been summarized in [2]:
"
  1. Observing Memory Modifications of Private Pages From A Child Process

  Long story short: process-private memory might not be as private as you
  think once you fork(): successive modifications of private memory
  regions in the parent process can still be observed by the child
  process, for example, by smart use of vmsplice()+munmap().

  The core problem is that pinning pages readable in a child process, such
  as done via the vmsplice system call, can result in a child process
  observing memory modifications done in the parent process the child is
  not supposed to observe. [1] contains an excellent summary and [2]
  contains further details. This issue was assigned CVE-2020-29374 [9].

  For this to trigger, it's required to use a fork() without subsequent
  exec(), for example, as used under Android zygote. Without further
  details about an application that forks less-privileged child processes,
  one cannot really say what's actually affected and what's not -- see the
  details section the end of this mail for a short sshd/openssh analysis.

  While commit 1783985 ("gup: document and work around "COW can break
  either way" issue") fixed this issue and resulted in other problems
  (e.g., ptrace on pmem), commit 09854ba ("mm: do_wp_page()
  simplification") re-introduced part of the problem unfortunately.

  The original reproducer can be modified quite easily to use THP [3] and
  make the issue appear again on upstream kernels. I modified it to use
  hugetlb [4] and it triggers as well. The problem is certainly less
  severe with hugetlb than with THP; it merely highlights that we still
  have plenty of open holes we should be closing/fixing.

  Regarding vmsplice(), the only known workaround is to disallow the
  vmsplice() system call ... or disable THP and hugetlb. But who knows
  what else is affected (RDMA? O_DIRECT?) to achieve the same goal -- in
  the end, it's a more generic issue.
"

This security issue was first reported by Jann Horn on 27 May 2020 and it
currently affects anonymous pages during swapin, anonymous THP and hugetlb.
This series tackles anonymous pages during swapin and anonymous THP:
* do_swap_page() for handling COW on PTEs during swapin directly
* do_huge_pmd_wp_page() for handling COW on PMD-mapped THP during write
  faults

With this series, we'll apply the same COW logic we have in do_wp_page()
to all swappable anon pages: don't reuse (map writable) the page in
case there are additional references (page_count() != 1). All users of
reuse_swap_page() are remove, and consequently reuse_swap_page() is
removed.

In general, we're struggling with the following COW-related issues:
(1) "missed COW": we miss to copy on write and reuse the page (map it
    writable) although we must copy because there are pending references
    from another process to this page. The result is a security issue.
(2) "wrong COW": we copy on write although we wouldn't have to and
    shouldn't: if there are valid GUP references, they will become out of
    sync with the pages mapped into the page table. We fail to detect that
    such a page can be reused safely, especially if never more than a
    single process mapped the page. The result is an intra process
    memory corruption.
(3) "unnecessary COW": we copy on write although we wouldn't have to:
    performance degradation and temporary increases swap+memory consumption
    can be the result.

While this series fixes (1) for swappable anon pages, it tries to reduce
reported cases of (3) first as good and easy as possible to limit the
impact when streamlining. The individual patches try to describe in which
cases we will run into (3).

This series certainly makes (2) worse for THP, because a THP will now get
PTE-mapped on write faults if there are additional references, even if
there was only ever a single process involved: once PTE-mapped, we'll copy
each and every subpage and won't reuse any subpage as long as the
underlying compound page wasn't split.

I'm working on an approach to fix (2) and improve (3): PageAnonExclusive to
mark anon pages that are exclusive to a single process, allow GUP pins only
on such exclusive pages, and allow turning exclusive pages shared
(clearing PageAnonExclusive) only if there are no GUP pins. Anon pages with
PageAnonExclusive set never have to be copied during write faults, but
eventually during fork() if they cannot be turned shared. The improved
reuse logic in this series will essentially also be the logic to reset
PageAnonExclusive. This work will certainly take a while, but I'm planning
on sharing details before having code fully ready.

#1-grate-driver#5 can be applied independently of the rest. grate-driver#6-grate-driver#9 are mostly only
cleanups related to reuse_swap_page().

Notes:
* For now, I'll leave hugetlb code untouched: "unnecessary COW" might
  easily break existing setups because hugetlb pages are a scarce resource
  and we could just end up having to crash the application when we run out
  of hugetlb pages. We have to be very careful and the security aspect with
  hugetlb is most certainly less relevant than for unprivileged anon pages.
* Instead of lru_add_drain() we might actually just drain the lru_add list
  or even just remove the single page of interest from the lru_add list.
  This would require a new helper function, and could be added if the
  conditional lru_add_drain() turn out to be a problem.
* I extended the test case already included in [1] to also test for the
  newly found do_swap_page() case. I'll send that out separately once/if
  this part was merged.

[1] https://lkml.kernel.org/r/[email protected]
[2] https://lore.kernel.org/r/[email protected]

This patch (of 9):

Liang Zhang reported [1] that the current COW logic in do_wp_page() is
sub-optimal when it comes to swap+read fault+write fault of anonymous
pages that have a single user, visible via a performance degradation in
the redis benchmark.  Something similar was previously reported [2] by
Nadav with a simple reproducer.

After we put an anon page into the swapcache and unmapped it from a single
process, that process might read that page again and refault it read-only.
If that process then writes to that page, the process is actually the
exclusive user of the page, however, the COW logic in do_co_page() won't
be able to reuse it due to the additional reference from the swapcache.

Let's optimize for pages that have been added to the swapcache but only
have an exclusive user.  Try removing the swapcache reference if there is
hope that we're the exclusive user.

We will fail removing the swapcache reference in two scenarios:
(1) There are additional swap entries referencing the page: copying
    instead of reusing is the right thing to do.
(2) The page is under writeback: theoretically we might be able to reuse
    in some cases, however, we cannot remove the additional reference
    and will have to copy.

Note that we'll only try removing the page from the swapcache when it's
highly likely that we'll be the exclusive owner after removing the page
from the swapache.  As we're about to map that page writable and redirty
it, that should not affect reclaim but is rather the right thing to do.

Further, we might have additional references from the LRU pagevecs, which
will force us to copy instead of being able to reuse.  We'll try handling
such references for some scenarios next.  Concurrent writeback cannot be
handled easily and we'll always have to copy.

While at it, remove the superfluous page_mapcount() check: it's
implicitly covered by the page_count() for ordinary anon pages.

[1] https://lkml.kernel.org/r/[email protected]
[2] https://lkml.kernel.org/r/[email protected]

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: David Hildenbrand <[email protected]>
Reported-by: Liang Zhang <[email protected]>
Reported-by: Nadav Amit <[email protected]>
Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Shakeel Butt <[email protected]>
Cc: John Hubbard <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Mike Kravetz <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Yang Shi <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Don Dutile <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Jan Kara <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Jul 31, 2023
[ Upstream commit 99d4850 ]

Found by leak sanitizer:
```
==1632594==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 21 byte(s) in 1 object(s) allocated from:
    #0 0x7f2953a7077b in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:439
    #1 0x556701d6fbbf in perf_env__read_cpuid util/env.c:369
    #2 0x556701d70589 in perf_env__cpuid util/env.c:465
    #3 0x55670204bba2 in x86__is_amd_cpu arch/x86/util/env.c:14
    #4 0x5567020487a2 in arch__post_evsel_config arch/x86/util/evsel.c:83
    #5 0x556701d8f78b in evsel__config util/evsel.c:1366
    #6 0x556701ef5872 in evlist__config util/record.c:108
    #7 0x556701cd6bcd in test__PERF_RECORD tests/perf-record.c:112
    #8 0x556701cacd07 in run_test tests/builtin-test.c:236
    grate-driver#9 0x556701cacfac in test_and_print tests/builtin-test.c:265
    grate-driver#10 0x556701cadddb in __cmd_test tests/builtin-test.c:402
    grate-driver#11 0x556701caf2aa in cmd_test tests/builtin-test.c:559
    grate-driver#12 0x556701d3b557 in run_builtin tools/perf/perf.c:323
    grate-driver#13 0x556701d3bac8 in handle_internal_command tools/perf/perf.c:377
    grate-driver#14 0x556701d3be90 in run_argv tools/perf/perf.c:421
    grate-driver#15 0x556701d3c3f8 in main tools/perf/perf.c:537
    grate-driver#16 0x7f2952a46189 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58

SUMMARY: AddressSanitizer: 21 byte(s) leaked in 1 allocation(s).
```

Fixes: f7b58cb ("perf mem/c2c: Add load store event mappings for AMD")
Signed-off-by: Ian Rogers <[email protected]>
Acked-by: Ravi Bangoria <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Jul 31, 2023
[ Upstream commit b684c09 ]

ppc_save_regs() skips one stack frame while saving the CPU register states.
Instead of saving current R1, it pulls the previous stack frame pointer.

When vmcores caused by direct panic call (such as `echo c >
/proc/sysrq-trigger`), are debugged with gdb, gdb fails to show the
backtrace correctly. On further analysis, it was found that it was because
of mismatch between r1 and NIP.

GDB uses NIP to get current function symbol and uses corresponding debug
info of that function to unwind previous frames, but due to the
mismatching r1 and NIP, the unwinding does not work, and it fails to
unwind to the 2nd frame and hence does not show the backtrace.

GDB backtrace with vmcore of kernel without this patch:

---------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=<optimized out>,
    newregs=0xc000000004f8f8d8) at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=<optimized out>) at kernel/kexec_core.c:974
 #2  0x0000000000000063 in ?? ()
 #3  0xc000000003579320 in ?? ()
---------

Further analysis revealed that the mismatch occurred because
"ppc_save_regs" was saving the previous stack's SP instead of the current
r1. This patch fixes this by storing current r1 in the saved pt_regs.

GDB backtrace with vmcore of patched kernel:

--------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=0x0, newregs=0xc00000000670b8d8)
    at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=regs@entry=0x0) at kernel/kexec_core.c:974
 #2  0xc000000000168918 in panic (fmt=fmt@entry=0xc000000001654a60 "sysrq triggered crash\n")
    at kernel/panic.c:358
 #3  0xc000000000b735f8 in sysrq_handle_crash (key=<optimized out>) at drivers/tty/sysrq.c:155
 #4  0xc000000000b742cc in __handle_sysrq (key=key@entry=99, check_mask=check_mask@entry=false)
    at drivers/tty/sysrq.c:602
 #5  0xc000000000b7506c in write_sysrq_trigger (file=<optimized out>, buf=<optimized out>,
    count=2, ppos=<optimized out>) at drivers/tty/sysrq.c:1163
 #6  0xc00000000069a7bc in pde_write (ppos=<optimized out>, count=<optimized out>,
    buf=<optimized out>, file=<optimized out>, pde=0xc00000000362cb40) at fs/proc/inode.c:340
 #7  proc_reg_write (file=<optimized out>, buf=<optimized out>, count=<optimized out>,
    ppos=<optimized out>) at fs/proc/inode.c:352
 #8  0xc0000000005b3bbc in vfs_write (file=file@entry=0xc000000006aa6b00,
    buf=buf@entry=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>,
    count=count@entry=2, pos=pos@entry=0xc00000000670bda0) at fs/read_write.c:582
 grate-driver#9  0xc0000000005b4264 in ksys_write (fd=<optimized out>,
    buf=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>, count=2)
    at fs/read_write.c:637
 grate-driver#10 0xc00000000002ea2c in system_call_exception (regs=0xc00000000670be80, r0=<optimized out>)
    at arch/powerpc/kernel/syscall.c:171
 grate-driver#11 0xc00000000000c270 in system_call_vectored_common ()
    at arch/powerpc/kernel/interrupt_64.S:192
--------

Nick adds:
  So this now saves regs as though it was an interrupt taken in the
  caller, at the instruction after the call to ppc_save_regs, whereas
  previously the NIP was there, but R1 came from the caller's caller and
  that mismatch is what causes gdb's dwarf unwinder to go haywire.

Signed-off-by: Aditya Gupta <[email protected]>
Fixes: d16a58f ("powerpc: Improve ppc_save_regs()")
Reivewed-by: Nicholas Piggin <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Dec 4, 2023
When scanning namespaces, it is possible to get valid data from the first
call to nvme_identify_ns() in nvme_alloc_ns(), but not from the second
call in nvme_update_ns_info_block().  In particular, if the NSID becomes
inactive between the two commands, a storage device may return a buffer
filled with zero as per 4.1.5.1.  In this case, we can get a kernel crash
due to a divide-by-zero in blk_stack_limits() because ns->lba_shift will
be set to zero.

PID: 326      TASK: ffff95fec3cd8000  CPU: 29   COMMAND: "kworker/u98:10"
 #0 [ffffad8f8702f9e0] machine_kexec at ffffffff91c76ec7
 #1 [ffffad8f8702fa38] __crash_kexec at ffffffff91dea4fa
 #2 [ffffad8f8702faf8] crash_kexec at ffffffff91deb788
 #3 [ffffad8f8702fb00] oops_end at ffffffff91c2e4bb
 #4 [ffffad8f8702fb20] do_trap at ffffffff91c2a4ce
 #5 [ffffad8f8702fb70] do_error_trap at ffffffff91c2a595
 #6 [ffffad8f8702fbb0] exc_divide_error at ffffffff928506e6
 #7 [ffffad8f8702fbd0] asm_exc_divide_error at ffffffff92a00926
    [exception RIP: blk_stack_limits+434]
    RIP: ffffffff92191872  RSP: ffffad8f8702fc80  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff95efa0c91800  RCX: 0000000000000001
    RDX: 0000000000000000  RSI: 0000000000000001  RDI: 0000000000000001
    RBP: 00000000ffffffff   R8: ffff95fec7df35a8   R9: 0000000000000000
    R10: 0000000000000000  R11: 0000000000000001  R12: 0000000000000000
    R13: 0000000000000000  R14: 0000000000000000  R15: ffff95fed33c09a8
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #8 [ffffad8f8702fce0] nvme_update_ns_info_block at ffffffffc06d3533 [nvme_core]
 grate-driver#9 [ffffad8f8702fd18] nvme_scan_ns at ffffffffc06d6fa7 [nvme_core]

This happened when the check for valid data was moved out of nvme_identify_ns()
into one of the callers.  Fix this by checking in both callers.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=218186
Fixes: 0dd6fff ("nvme: bring back auto-removal of deleted namespaces during sequential scan")
Cc: [email protected]
Signed-off-by: Ewan D. Milne <[email protected]>
Signed-off-by: Keith Busch <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Dec 18, 2023
Validate @smb->WordCount to avoid reading off the end of @smb and thus
causing the following KASAN splat:

  BUG: KASAN: slab-out-of-bounds in smbCalcSize+0x32/0x40 [cifs]
  Read of size 2 at addr ffff88801c024ec5 by task cifsd/1328

  CPU: 1 PID: 1328 Comm: cifsd Not tainted 6.7.0-rc5 grate-driver#9
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? smbCalcSize+0x32/0x40 [cifs]
   ? smbCalcSize+0x32/0x40 [cifs]
   kasan_check_range+0x105/0x1b0
   smbCalcSize+0x32/0x40 [cifs]
   checkSMB+0x162/0x370 [cifs]
   ? __pfx_checkSMB+0x10/0x10 [cifs]
   cifs_handle_standard+0xbc/0x2f0 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   cifs_demultiplex_thread+0xed1/0x1360 [cifs]
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lockdep_hardirqs_on_prepare+0x136/0x210
   ? __pfx_lock_release+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? mark_held_locks+0x1a/0x90
   ? lockdep_hardirqs_on_prepare+0x136/0x210
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kthread_parkme+0xce/0xf0
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   kthread+0x18d/0x1d0
   ? kthread+0xdb/0x1d0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x34/0x60
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1b/0x30
   </TASK>

This fixes CVE-2023-6606.

Reported-by: [email protected]
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218218
Cc: [email protected]
Signed-off-by: Paulo Alcantara (SUSE) <[email protected]>
Signed-off-by: Steve French <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Dec 19, 2023
Validate @smb->WordCount to avoid reading off the end of @smb and thus
causing the following KASAN splat:

  BUG: KASAN: slab-out-of-bounds in smbCalcSize+0x32/0x40 [cifs]
  Read of size 2 at addr ffff88801c024ec5 by task cifsd/1328

  CPU: 1 PID: 1328 Comm: cifsd Not tainted 6.7.0-rc5 grate-driver#9
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? smbCalcSize+0x32/0x40 [cifs]
   ? smbCalcSize+0x32/0x40 [cifs]
   kasan_check_range+0x105/0x1b0
   smbCalcSize+0x32/0x40 [cifs]
   checkSMB+0x162/0x370 [cifs]
   ? __pfx_checkSMB+0x10/0x10 [cifs]
   cifs_handle_standard+0xbc/0x2f0 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   cifs_demultiplex_thread+0xed1/0x1360 [cifs]
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lockdep_hardirqs_on_prepare+0x136/0x210
   ? __pfx_lock_release+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? mark_held_locks+0x1a/0x90
   ? lockdep_hardirqs_on_prepare+0x136/0x210
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kthread_parkme+0xce/0xf0
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   kthread+0x18d/0x1d0
   ? kthread+0xdb/0x1d0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x34/0x60
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1b/0x30
   </TASK>

This fixes CVE-2023-6606.

Reported-by: [email protected]
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218218
Cc: [email protected]
Signed-off-by: Paulo Alcantara (SUSE) <[email protected]>
Signed-off-by: Steve French <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Dec 27, 2023
Jiri Pirko says:

====================
devlink: introduce notifications filtering

From: Jiri Pirko <[email protected]>

Currently the user listening on a socket for devlink notifications
gets always all messages for all existing devlink instances and objects,
even if he is interested only in one of those. That may cause
unnecessary overhead on setups with thousands of instances present.

User is currently able to narrow down the devlink objects replies
to dump commands by specifying select attributes.

Allow similar approach for notifications providing user a new
notify-filter-set command to select attributes with values
the notification message has to match. In that case, it is delivered
to the socket.

Note that the filtering is done per-socket, so multiple users may
specify different selection of attributes with values.

This patchset initially introduces support for following attributes:
DEVLINK_ATTR_BUS_NAME
DEVLINK_ATTR_DEV_NAME
DEVLINK_ATTR_PORT_INDEX

Patches #1 - #4 are preparations in devlink code, patch #3 is
                an optimization done on the way.
Patches #5 - #7 are preparations in netlink and generic netlink code.
Patch #8 is the main one in this set implementing of
         the notify-filter-set command and the actual
         per-socket filtering.
Patch grate-driver#9 extends the infrastructure allowing to filter according
         to a port index.

Example:
$ devlink mon port pci/0000:08:00.0/32768
[port,new] pci/0000:08:00.0/32768: type notset flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type eth flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type eth netdev eth3 flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type eth netdev eth3 flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type eth flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,new] pci/0000:08:00.0/32768: type notset flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
[port,del] pci/0000:08:00.0/32768: type notset flavour pcisf controller 0 pfnum 0 sfnum 107 splittable false
  function:
    hw_addr 00:00:00:00:00:00 state inactive opstate detached roce enable
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Dec 27, 2023
Andrii Nakryiko says:

====================
Enhance BPF global subprogs with argument tags

This patch set adds verifier support for annotating user's global BPF subprog
arguments with few commonly requested annotations, to improve global subprog
verification experience.

These tags are:
  - ability to annotate a special PTR_TO_CTX argument;
  - ability to annotate a generic PTR_TO_MEM as non-null.

We utilize btf_decl_tag attribute for this and provide two helper macros as
part of bpf_helpers.h in libbpf (patch #8).

Besides this we also add abilit to pass a pointer to dynptr into global
subprog. This is done based on type name match (struct bpf_dynptr *). This
allows to pass dynptrs into global subprogs, for use cases that deal with
variable-sized generic memory pointers.

Big chunk of the patch set (patches #1 through #5) are various refactorings to
make verifier internals around global subprog validation logic easier to
extend and support long term, eliminating BTF parsing logic duplication,
factoring out argument expectation definitions from BTF parsing, etc.

New functionality is added in patch #6 (ctx and non-null) and patch #7
(dynptr), extending global subprog checks with awareness for arg tags.

Patch grate-driver#9 adds simple tests validating each of the added tags and dynptr
argument passing.

Patch grate-driver#10 adds a simple negative case for freplace programs to make sure that
target BPF programs with "unreliable" BTF func proto cannot be freplaced.

v2->v3:
  - patch grate-driver#10 improved by checking expected verifier error (Eduard);
v1->v2:
  - dropped packet args for now (Eduard);
  - added back unreliable=true detection for entry BPF programs (Eduard);
  - improved subprog arg validation (Eduard);
  - switched dynptr arg from tag to just type name based check (Eduard).
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Dec 27, 2023
Ido Schimmel says:

====================
Add MDB bulk deletion support

This patchset adds MDB bulk deletion support, allowing user space to
request the deletion of matching entries instead of dumping the entire
MDB and issuing a separate deletion request for each matching entry.
Support is added in both the bridge and VXLAN drivers in a similar
fashion to the existing FDB bulk deletion support.

The parameters according to which bulk deletion can be performed are
similar to the FDB ones, namely: Destination port, VLAN ID, state (e.g.,
"permanent"), routing protocol, source / destination VNI, destination IP
and UDP port. Flushing based on flags (e.g., "offload", "fast_leave",
"added_by_star_ex", "blocked") is not currently supported, but can be
added in the future, if a use case arises.

Patch #1 adds a new uAPI attribute to allow specifying the state mask
according to which bulk deletion will be performed, if any.

Patch #2 adds a new policy according to which bulk deletion requests
(with 'NLM_F_BULK' flag set) will be parsed.

Patches #3-#4 add a new NDO for MDB bulk deletion and invoke it from the
rtnetlink code when a bulk deletion request is made.

Patches #5-#6 implement the MDB bulk deletion NDO in the bridge and
VXLAN drivers, respectively.

Patch #7 allows user space to issue MDB bulk deletion requests by no
longer rejecting the 'NLM_F_BULK' flag when it is set in 'RTM_DELMDB'
requests.

Patches #8-grate-driver#9 add selftests for both drivers, for both good and bad
flows.

iproute2 changes can be found here [1].

https://github.com/idosch/iproute2/tree/submit/mdb_flush_v1
====================

Signed-off-by: David S. Miller <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Dec 27, 2023
An issue occurred while reading an ELF file in libbpf.c during fuzzing:

	Program received signal SIGSEGV, Segmentation fault.
	0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	4206 in libbpf.c
	(gdb) bt
	#0 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	#1 0x000000000094f9d6 in bpf_object.collect_relos () at libbpf.c:6706
	#2 0x000000000092bef3 in bpf_object_open () at libbpf.c:7437
	#3 0x000000000092c046 in bpf_object.open_mem () at libbpf.c:7497
	#4 0x0000000000924afa in LLVMFuzzerTestOneInput () at fuzz/bpf-object-fuzzer.c:16
	#5 0x000000000060be11 in testblitz_engine::fuzzer::Fuzzer::run_one ()
	#6 0x000000000087ad92 in tracing::span::Span::in_scope ()
	#7 0x00000000006078aa in testblitz_engine::fuzzer::util::walkdir ()
	#8 0x00000000005f3217 in testblitz_engine::entrypoint::main::{{closure}} ()
	grate-driver#9 0x00000000005f2601 in main ()
	(gdb)

scn_data was null at this code(tools/lib/bpf/src/libbpf.c):

	if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) {

The scn_data is derived from the code above:

	scn = elf_sec_by_idx(obj, sec_idx);
	scn_data = elf_sec_data(obj, scn);

	relo_sec_name = elf_sec_str(obj, shdr->sh_name);
	sec_name = elf_sec_name(obj, scn);
	if (!relo_sec_name || !sec_name)// don't check whether scn_data is NULL
		return -EINVAL;

In certain special scenarios, such as reading a malformed ELF file,
it is possible that scn_data may be a null pointer

Signed-off-by: Mingyi Zhang <[email protected]>
Signed-off-by: Xin Liu <[email protected]>
Signed-off-by: Changye Wu <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Daniel Borkmann <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
okias pushed a commit to okias/linux that referenced this issue Jan 7, 2024
[ Upstream commit a84fbf2 ]

Generating metrics llc_code_read_mpi_demand_plus_prefetch,
llc_data_read_mpi_demand_plus_prefetch,
llc_miss_local_memory_bandwidth_read,
llc_miss_local_memory_bandwidth_write,
nllc_miss_remote_memory_bandwidth_read, memory_bandwidth_read,
memory_bandwidth_write, uncore_frequency, upi_data_transmit_bw,
C2_Pkg_Residency, C3_Core_Residency, C3_Pkg_Residency,
C6_Core_Residency, C6_Pkg_Residency, C7_Core_Residency,
C7_Pkg_Residency, UNCORE_FREQ and tma_info_system_socket_clks would
trigger an address sanitizer heap-buffer-overflows on a SkylakeX.

```
==2567752==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x5020003ed098 at pc 0x5621a816654e bp 0x7fffb55d4da0 sp 0x7fffb55d4d98
READ of size 4 at 0x5020003eee78 thread T0
    #0 0x558265d6654d in aggr_cpu_id__is_empty tools/perf/util/cpumap.c:694:12
    #1 0x558265c914da in perf_stat__get_aggr tools/perf/builtin-stat.c:1490:6
    #2 0x558265c914da in perf_stat__get_global_cached tools/perf/builtin-stat.c:1530:9
    #3 0x558265e53290 in should_skip_zero_counter tools/perf/util/stat-display.c:947:31
    #4 0x558265e53290 in print_counter_aggrdata tools/perf/util/stat-display.c:985:18
    #5 0x558265e51931 in print_counter tools/perf/util/stat-display.c:1110:3
    #6 0x558265e51931 in evlist__print_counters tools/perf/util/stat-display.c:1571:5
    #7 0x558265c8ec87 in print_counters tools/perf/builtin-stat.c:981:2
    #8 0x558265c8cc71 in cmd_stat tools/perf/builtin-stat.c:2837:3
    grate-driver#9 0x558265bb9bd4 in run_builtin tools/perf/perf.c:323:11
    grate-driver#10 0x558265bb98eb in handle_internal_command tools/perf/perf.c:377:8
    grate-driver#11 0x558265bb9389 in run_argv tools/perf/perf.c:421:2
    grate-driver#12 0x558265bb9389 in main tools/perf/perf.c:537:3
```

The issue was the use of testing a cpumap with NULL rather than using
empty, as a map containing the dummy value isn't NULL and the -1
results in an empty aggr map being allocated which legitimately
overflows when any member is accessed.

Fixes: 8a96f45 ("perf stat: Avoid SEGV if core.cpus isn't set")
Signed-off-by: Ian Rogers <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Jan 7, 2024
[ Upstream commit ede72dc ]

Fuzzing found that an invalid tracepoint name would create a memory
leak with an address sanitizer build:
```
$ perf stat -e '*:o/' true
event syntax error: '*:o/'
                       \___ parser error
Run 'perf list' for a list of valid events

 Usage: perf stat [<options>] [<command>]

    -e, --event <event>   event selector. use 'perf list' to list available events

=================================================================
==59380==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 4 byte(s) in 2 object(s) allocated from:
    #0 0x7f38ac07077b in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:439
    #1 0x55f2f41be73b in str util/parse-events.l:49
    #2 0x55f2f41d08e8 in parse_events_lex util/parse-events.l:338
    #3 0x55f2f41dc3b1 in parse_events_parse util/parse-events-bison.c:1464
    #4 0x55f2f410b8b3 in parse_events__scanner util/parse-events.c:1822
    #5 0x55f2f410d1b9 in __parse_events util/parse-events.c:2094
    #6 0x55f2f410e57f in parse_events_option util/parse-events.c:2279
    #7 0x55f2f4427b56 in get_value tools/lib/subcmd/parse-options.c:251
    #8 0x55f2f4428d98 in parse_short_opt tools/lib/subcmd/parse-options.c:351
    grate-driver#9 0x55f2f4429d80 in parse_options_step tools/lib/subcmd/parse-options.c:539
    grate-driver#10 0x55f2f442acb9 in parse_options_subcommand tools/lib/subcmd/parse-options.c:654
    grate-driver#11 0x55f2f3ec99fc in cmd_stat tools/perf/builtin-stat.c:2501
    grate-driver#12 0x55f2f4093289 in run_builtin tools/perf/perf.c:322
    grate-driver#13 0x55f2f40937f5 in handle_internal_command tools/perf/perf.c:375
    grate-driver#14 0x55f2f4093bbd in run_argv tools/perf/perf.c:419
    grate-driver#15 0x55f2f409412b in main tools/perf/perf.c:535

SUMMARY: AddressSanitizer: 4 byte(s) leaked in 2 allocation(s).
```
Fix by adding the missing destructor.

Fixes: 865582c ("perf tools: Adds the tracepoint name parsing support")
Signed-off-by: Ian Rogers <[email protected]>
Cc: He Kuang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Jan 7, 2024
commit d8b90d6 upstream.

When scanning namespaces, it is possible to get valid data from the first
call to nvme_identify_ns() in nvme_alloc_ns(), but not from the second
call in nvme_update_ns_info_block().  In particular, if the NSID becomes
inactive between the two commands, a storage device may return a buffer
filled with zero as per 4.1.5.1.  In this case, we can get a kernel crash
due to a divide-by-zero in blk_stack_limits() because ns->lba_shift will
be set to zero.

PID: 326      TASK: ffff95fec3cd8000  CPU: 29   COMMAND: "kworker/u98:10"
 #0 [ffffad8f8702f9e0] machine_kexec at ffffffff91c76ec7
 #1 [ffffad8f8702fa38] __crash_kexec at ffffffff91dea4fa
 #2 [ffffad8f8702faf8] crash_kexec at ffffffff91deb788
 #3 [ffffad8f8702fb00] oops_end at ffffffff91c2e4bb
 #4 [ffffad8f8702fb20] do_trap at ffffffff91c2a4ce
 #5 [ffffad8f8702fb70] do_error_trap at ffffffff91c2a595
 #6 [ffffad8f8702fbb0] exc_divide_error at ffffffff928506e6
 #7 [ffffad8f8702fbd0] asm_exc_divide_error at ffffffff92a00926
    [exception RIP: blk_stack_limits+434]
    RIP: ffffffff92191872  RSP: ffffad8f8702fc80  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff95efa0c91800  RCX: 0000000000000001
    RDX: 0000000000000000  RSI: 0000000000000001  RDI: 0000000000000001
    RBP: 00000000ffffffff   R8: ffff95fec7df35a8   R9: 0000000000000000
    R10: 0000000000000000  R11: 0000000000000001  R12: 0000000000000000
    R13: 0000000000000000  R14: 0000000000000000  R15: ffff95fed33c09a8
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #8 [ffffad8f8702fce0] nvme_update_ns_info_block at ffffffffc06d3533 [nvme_core]
 grate-driver#9 [ffffad8f8702fd18] nvme_scan_ns at ffffffffc06d6fa7 [nvme_core]

This happened when the check for valid data was moved out of nvme_identify_ns()
into one of the callers.  Fix this by checking in both callers.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=218186
Fixes: 0dd6fff ("nvme: bring back auto-removal of deleted namespaces during sequential scan")
Cc: [email protected]
Signed-off-by: Ewan D. Milne <[email protected]>
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
okias pushed a commit to okias/linux that referenced this issue Jan 7, 2024
[ Upstream commit e3e82fc ]

When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   grate-driver#9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   grate-driver#10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   grate-driver#11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   grate-driver#12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   grate-driver#13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   grate-driver#14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   grate-driver#15 [ffff88aa841efb88] device_del at ffffffff82179d23
   grate-driver#16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   grate-driver#17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   grate-driver#18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   grate-driver#19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   grate-driver#20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   grate-driver#21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/[email protected]
Suggested-by: "Ismail, Mustafa" <[email protected]>
Signed-off-by: Shifeng Li <[email protected]>
Reviewed-by: Shiraz Saleem <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
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