From c060bc7c44829a85f4ebbcb016890a87619f8a69 Mon Sep 17 00:00:00 2001
From: Pawel Wieczorkiewicz <wipawel@amazon.de>
Date: Mon, 26 Oct 2020 15:03:55 +0100
Subject: [PATCH] asm: use proper page size alignment

Stack should start at page boundary.
Use PAGE_SIZE macro where possible.

Signed-off-by: Pawel Wieczorkiewicz <wipawel@amazon.de>
---
 arch/x86/boot/head.S       | 5 ++++-
 arch/x86/boot/pagetables.S | 6 +++---
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/arch/x86/boot/head.S b/arch/x86/boot/head.S
index 8c435cdf..f3d180b4 100644
--- a/arch/x86/boot/head.S
+++ b/arch/x86/boot/head.S
@@ -23,6 +23,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include <asm-macros.h>
+#include <page.h>
 #include <processor.h>
 #include <segment.h>
 
@@ -95,15 +96,17 @@ GLOBAL(_start)
 
     ud2
 
-SECTION(.bss.init, "aw", 16)
+SECTION(.bss.init, "aw", PAGE_SIZE)
 _boot_stack:
     .skip BOOT_STACK_SIZE
 GLOBAL(_boot_stack_top)
 
+.align PAGE_SIZE
 _boot_stack_ist:
     .skip BOOT_STACK_SIZE
 GLOBAL(_boot_stack_ist_top)
 
+.align PAGE_SIZE
 _boot_stack_df:
     .skip BOOT_STACK_SIZE
 GLOBAL(_boot_stack_df_top)
diff --git a/arch/x86/boot/pagetables.S b/arch/x86/boot/pagetables.S
index b026e885..4eb6d3bb 100644
--- a/arch/x86/boot/pagetables.S
+++ b/arch/x86/boot/pagetables.S
@@ -29,7 +29,7 @@
 #define _PADDR(table, shift) (((. - (table)) / PTE_SIZE) << (shift))
 
 /* Initial identity map page tables */
-SECTION(.data.init, "aw", 0x1000)
+SECTION(.data.init, "aw", PAGE_SIZE)
 GLOBAL(l1_pt_entries)
     .rept L1_PT_ENTRIES
     .long _PADDR(l1_pt_entries, L1_PT_SHIFT) + L1_PROT, 0
@@ -42,7 +42,7 @@ GLOBAL(l2_pt_entries)
 END_OBJECT(l2_pt_entries)
 
 #if defined(__i386__)
-.align 0x1000
+.align PAGE_SIZE
 #endif
 GLOBAL(l3_pt_entries)
     .long l2_pt_entries + L3_PROT, 0
@@ -55,7 +55,7 @@ GLOBAL(l3_pt_entries)
 END_OBJECT(l3_pt_entries)
 
 #if defined(__x86_64__)
-.align 0x1000
+.align PAGE_SIZE
 GLOBAL(l4_pt_entries)
     .long l3_pt_entries + L4_PROT, 0