From 131c4bda1665e57d7d85081a2b9249334f46d7e7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= Date: Fri, 28 Jun 2024 17:38:48 +0200 Subject: [PATCH] drm/ttm: Always take the bo delayed cleanup path for imported bos MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Bos can be put with multiple unrelated dma-resv locks held. But imported bos attempt to grab the bo dma-resv during dma-buf detach that typically happens during cleanup. That leads to lockde splats similar to the below and a potential ABBA deadlock. Fix this by always taking the delayed workqueue cleanup path for imported bos. Requesting stable fixes from when the Xe driver was introduced, since its usage of drm_exec and wide vm dma_resvs appear to be the first reliable trigger of this. [22982.116427] ============================================ [22982.116428] WARNING: possible recursive locking detected [22982.116429] 6.10.0-rc2+ #10 Tainted: G U W [22982.116430] -------------------------------------------- [22982.116430] glxgears:sh0/5785 is trying to acquire lock: [22982.116431] ffff8c2bafa539a8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_detach+0x3b/0xf0 [22982.116438] but task is already holding lock: [22982.116438] ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116442] other info that might help us debug this: [22982.116442] Possible unsafe locking scenario: [22982.116443] CPU0 [22982.116444] ---- [22982.116444] lock(reservation_ww_class_mutex); [22982.116445] lock(reservation_ww_class_mutex); [22982.116447] *** DEADLOCK *** [22982.116447] May be due to missing lock nesting notation [22982.116448] 5 locks held by glxgears:sh0/5785: [22982.116449] #0: ffff8c2d9aba58c8 (&xef->vm.lock){+.+.}-{3:3}, at: xe_file_close+0xde/0x1c0 [xe] [22982.116507] #1: ffff8c2e28cc8480 (&vm->lock){++++}-{3:3}, at: xe_vm_close_and_put+0x161/0x9b0 [xe] [22982.116578] #2: ffff8c2e31982970 (&val->lock){.+.+}-{3:3}, at: xe_validation_ctx_init+0x6d/0x70 [xe] [22982.116647] #3: ffffacdc469478a8 (reservation_ww_class_acquire){+.+.}-{0:0}, at: xe_vma_destroy_unlocked+0x7f/0xe0 [xe] [22982.116716] #4: ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116719] stack backtrace: [22982.116720] CPU: 8 PID: 5785 Comm: glxgears:sh0 Tainted: G U W 6.10.0-rc2+ #10 [22982.116721] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023 [22982.116723] Call Trace: [22982.116724] [22982.116725] dump_stack_lvl+0x77/0xb0 [22982.116727] __lock_acquire+0x1232/0x2160 [22982.116730] lock_acquire+0xcb/0x2d0 [22982.116732] ? dma_buf_detach+0x3b/0xf0 [22982.116734] ? __lock_acquire+0x417/0x2160 [22982.116736] __ww_mutex_lock.constprop.0+0xd0/0x13b0 [22982.116738] ? dma_buf_detach+0x3b/0xf0 [22982.116741] ? dma_buf_detach+0x3b/0xf0 [22982.116743] ? ww_mutex_lock+0x2b/0x90 [22982.116745] ww_mutex_lock+0x2b/0x90 [22982.116747] dma_buf_detach+0x3b/0xf0 [22982.116749] drm_prime_gem_destroy+0x2f/0x40 [drm] [22982.116775] xe_ttm_bo_destroy+0x32/0x220 [xe] [22982.116818] ? __mutex_unlock_slowpath+0x3a/0x290 [22982.116821] drm_exec_unlock_all+0xa1/0xd0 [drm_exec] [22982.116823] drm_exec_fini+0x12/0xb0 [drm_exec] [22982.116824] xe_validation_ctx_fini+0x15/0x40 [xe] [22982.116892] xe_vma_destroy_unlocked+0xb1/0xe0 [xe] [22982.116959] xe_vm_close_and_put+0x41a/0x9b0 [xe] [22982.117025] ? xa_find+0xe3/0x1e0 [22982.117028] xe_file_close+0x10a/0x1c0 [xe] [22982.117074] drm_file_free+0x22a/0x280 [drm] [22982.117099] drm_release_noglobal+0x22/0x70 [drm] [22982.117119] __fput+0xf1/0x2d0 [22982.117122] task_work_run+0x59/0x90 [22982.117125] do_exit+0x330/0xb40 [22982.117127] do_group_exit+0x36/0xa0 [22982.117129] get_signal+0xbd2/0xbe0 [22982.117131] arch_do_signal_or_restart+0x3e/0x240 [22982.117134] syscall_exit_to_user_mode+0x1e7/0x290 [22982.117137] do_syscall_64+0xa1/0x180 [22982.117139] ? lock_acquire+0xcb/0x2d0 [22982.117140] ? __set_task_comm+0x28/0x1e0 [22982.117141] ? find_held_lock+0x2b/0x80 [22982.117144] ? __set_task_comm+0xe1/0x1e0 [22982.117145] ? lock_release+0xca/0x290 [22982.117147] ? __do_sys_prctl+0x245/0xab0 [22982.117149] ? lockdep_hardirqs_on_prepare+0xde/0x190 [22982.117150] ? syscall_exit_to_user_mode+0xb0/0x290 [22982.117152] ? do_syscall_64+0xa1/0x180 [22982.117154] ? __lock_acquire+0x417/0x2160 [22982.117155] ? reacquire_held_locks+0xd1/0x1f0 [22982.117156] ? do_user_addr_fault+0x30c/0x790 [22982.117158] ? lock_acquire+0xcb/0x2d0 [22982.117160] ? find_held_lock+0x2b/0x80 [22982.117162] ? do_user_addr_fault+0x357/0x790 [22982.117163] ? lock_release+0xca/0x290 [22982.117164] ? do_user_addr_fault+0x361/0x790 [22982.117166] ? trace_hardirqs_off+0x4b/0xc0 [22982.117168] ? clear_bhb_loop+0x45/0xa0 [22982.117170] ? clear_bhb_loop+0x45/0xa0 [22982.117172] ? clear_bhb_loop+0x45/0xa0 [22982.117174] entry_SYSCALL_64_after_hwframe+0x76/0x7e [22982.117176] RIP: 0033:0x7f943d267169 [22982.117192] Code: Unable to access opcode bytes at 0x7f943d26713f. [22982.117193] RSP: 002b:00007f9430bffc80 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [22982.117195] RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 00007f943d267169 [22982.117196] RDX: 0000000000000000 RSI: 0000000000000189 RDI: 00005622f89579d0 [22982.117197] RBP: 00007f9430bffcb0 R08: 0000000000000000 R09: 00000000ffffffff [22982.117198] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [22982.117199] R13: 0000000000000000 R14: 0000000000000000 R15: 00005622f89579d0 [22982.117202] Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs") Cc: Christian König Cc: Daniel Vetter Cc: dri-devel@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Cc: # v6.8+ Signed-off-by: Thomas Hellström Reviewed-by: Matthew Brost Reviewed-by: Daniel Vetter Reviewed-by: Christian König Link: https://patchwork.freedesktop.org/patch/msgid/20240628153848.4989-1-thomas.hellstrom@linux.intel.com --- drivers/gpu/drm/ttm/ttm_bo.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 470515a1587..37ea0381e72 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -346,6 +346,7 @@ static void ttm_bo_release(struct kref *kref) if (!dma_resv_test_signaled(bo->base.resv, DMA_RESV_USAGE_BOOKKEEP) || (want_init_on_free() && (bo->ttm != NULL)) || + bo->type == ttm_bo_type_sg || !dma_resv_trylock(bo->base.resv)) { /* The BO is not idle, resurrect it for delayed destroy */ ttm_bo_flush_all_fences(bo);