diff options
| author | Xiaoyao Li <[email protected]> | 2019-06-27 12:55:25 +0800 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2019-06-27 10:56:11 +0200 |
| commit | 2238246ff8d533a5f2327d1f953375876d8a013c (patch) | |
| tree | e3b64cc4f0c0979b156aeb489e24c1d98d51fddc | |
| parent | 5a949b38839e284b1307540c56b03caf57da9736 (diff) | |
x86/boot: Make the GDT 8-byte aligned
The segment descriptors are loaded with an implicitly LOCK-ed instruction,
which could trigger the split lock #AC exception if the variable is not
properly aligned and crosses a cache line.
Align the GDT properly so the descriptors are all 8 byte aligned.
Signed-off-by: Xiaoyao Li <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Fenghua Yu <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/boot/compressed/head_64.S | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index fafb75c6c592..6233ae35d0d9 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -659,6 +659,7 @@ no_longmode: gdt64: .word gdt_end - gdt .quad 0 + .balign 8 gdt: .word gdt_end - gdt .long gdt |