Commit acba44d2 authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

x86/copy_user_64: Remove .fixup usage 



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

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: default avatarBorislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211110101325.068505810@infradead.org
parent c6dbd3e5

arch/x86/lib/copy_user_64.S

+11 −21
Original line number Diff line number Diff line
@@ -32,13 +32,9 @@ 
	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)

	_ASM_EXTABLE_CPY(100b, .Lcopy_user_handle_align)

	_ASM_EXTABLE_CPY(101b, .Lcopy_user_handle_align)

.endm



/*
@@ -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)