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x86/copy_user_64: Remove .fixup usage

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Place the anonymous .fixup code at the tail of the regular functions.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211110101325.068505810@infradead.org
This commit is contained in:
Peter Zijlstra 2021-11-10 11:01:05 +01:00
parent c6dbd3e5e6
commit acba44d243
1 changed files with 11 additions and 21 deletions
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32
arch/x86/lib/copy_user_64.S
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@ -32,14 +32,10 @@
decl %ecx
jnz 100b
102:
.section .fixup,"ax"
103: addl %ecx,%edx /* ecx is zerorest also */
jmp .Lcopy_user_handle_tail
.previous
_ASM_EXTABLE_CPY(100b, 103b)
_ASM_EXTABLE_CPY(101b, 103b)
.endm
_ASM_EXTABLE_CPY(100b, .Lcopy_user_handle_align)
_ASM_EXTABLE_CPY(101b, .Lcopy_user_handle_align)
.endm
/*
* copy_user_generic_unrolled - memory copy with exception handling.
@ -107,7 +103,6 @@ SYM_FUNC_START(copy_user_generic_unrolled)
ASM_CLAC
RET
.section .fixup,"ax"
30: shll $6,%ecx
addl %ecx,%edx
jmp 60f
@ -115,7 +110,6 @@ SYM_FUNC_START(copy_user_generic_unrolled)
jmp 60f
50: movl %ecx,%edx
60: jmp .Lcopy_user_handle_tail /* ecx is zerorest also */
.previous
_ASM_EXTABLE_CPY(1b, 30b)
_ASM_EXTABLE_CPY(2b, 30b)
@ -166,20 +160,16 @@ SYM_FUNC_START(copy_user_generic_string)
movl %edx,%ecx
shrl $3,%ecx
andl $7,%edx
1: rep
movsq
1: rep movsq
2: movl %edx,%ecx
3: rep
movsb
3: rep movsb
xorl %eax,%eax
ASM_CLAC
RET
.section .fixup,"ax"
11: leal (%rdx,%rcx,8),%ecx
12: movl %ecx,%edx /* ecx is zerorest also */
jmp .Lcopy_user_handle_tail
.previous
_ASM_EXTABLE_CPY(1b, 11b)
_ASM_EXTABLE_CPY(3b, 12b)
@ -203,16 +193,13 @@ SYM_FUNC_START(copy_user_enhanced_fast_string)
cmpl $64,%edx
jb .L_copy_short_string /* less then 64 bytes, avoid the costly 'rep' */
movl %edx,%ecx
1: rep
movsb
1: rep movsb
xorl %eax,%eax
ASM_CLAC
RET
.section .fixup,"ax"
12: movl %ecx,%edx /* ecx is zerorest also */
jmp .Lcopy_user_handle_tail
.previous
_ASM_EXTABLE_CPY(1b, 12b)
SYM_FUNC_END(copy_user_enhanced_fast_string)
@ -240,6 +227,11 @@ SYM_CODE_START_LOCAL(.Lcopy_user_handle_tail)
RET
_ASM_EXTABLE_CPY(1b, 2b)
.Lcopy_user_handle_align:
addl %ecx,%edx /* ecx is zerorest also */
jmp .Lcopy_user_handle_tail
SYM_CODE_END(.Lcopy_user_handle_tail)
/*
@ -350,7 +342,6 @@ SYM_FUNC_START(__copy_user_nocache)
sfence
RET
.section .fixup,"ax"
.L_fixup_4x8b_copy:
shll $6,%ecx
addl %ecx,%edx
@ -366,7 +357,6 @@ SYM_FUNC_START(__copy_user_nocache)
.L_fixup_handle_tail:
sfence
jmp .Lcopy_user_handle_tail
.previous
_ASM_EXTABLE_CPY(1b, .L_fixup_4x8b_copy)
_ASM_EXTABLE_CPY(2b, .L_fixup_4x8b_copy)