Commit 6829f198 authored by Uros Bizjak's avatar Uros Bizjak Committed by Ingo Molnar
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x86/process/32: Use correct type for 'gs' variable in __show_regs() to avoid zero-extension 



Change the type of 'gs' variable in __show_regs() from
'unsigned short' to 'unsigned int'. This prevents unwanted
zero-extension when storing the 16-bit segment register
into a wider general purpose register.

The code improves from:

  50:	8c ee                	mov    %gs,%esi
  52:	0f b7 f6             	movzwl %si,%esi
  ...
  be:	89 74 24 14          	mov    %esi,0x14(%esp)

to:

  50:	8c ef                	mov    %gs,%edi
  ...
  bb:	89 7c 24 14          	mov    %edi,0x14(%esp)

No functional change intended.

Signed-off-by: default avatarUros Bizjak <ubizjak@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://patch.msgid.link/20260330085938.67985-3-ubizjak@gmail.com
parent 81310ce4

arch/x86/kernel/process_32.c

+1 −1
Original line number Diff line number Diff line
@@ -61,7 +61,7 @@ void __show_regs(struct pt_regs *regs, enum show_regs_mode mode, 
{

	unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L;

	unsigned long d0, d1, d2, d3, d6, d7;

	unsigned short gs;

	unsigned int gs;



	savesegment(gs, gs);