Merge tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 core updates from Borislav Petkov:

 - Get rid of all the .fixup sections because this generates
   misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and
   LIVEPATCH as the backtrace misses the function which is being fixed
   up.

 - Add Straight Line Speculation mitigation support which uses a new
   compiler switch -mharden-sls= which sticks an INT3 after a RET or an
   indirect branch in order to block speculation after them. Reportedly,
   CPUs do speculate behind such insns.

 - The usual set of cleanups and improvements

* tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  x86/entry_32: Fix segment exceptions
  objtool: Remove .fixup handling
  x86: Remove .fixup section
  x86/word-at-a-time: Remove .fixup usage
  x86/usercopy: Remove .fixup usage
  x86/usercopy_32: Simplify __copy_user_intel_nocache()
  x86/sgx: Remove .fixup usage
  x86/checksum_32: Remove .fixup usage
  x86/vmx: Remove .fixup usage
  x86/kvm: Remove .fixup usage
  x86/segment: Remove .fixup usage
  x86/fpu: Remove .fixup usage
  x86/xen: Remove .fixup usage
  x86/uaccess: Remove .fixup usage
  x86/futex: Remove .fixup usage
  x86/msr: Remove .fixup usage
  x86/extable: Extend extable functionality
  x86/entry_32: Remove .fixup usage
  x86/entry_64: Remove .fixup usage
  x86/copy_mc_64: Remove .fixup usage
  ...

1 files changed, 16 insertions, 26 deletions

diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index a2cbeae4b180..8ca5ecf16dc4 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -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.
@@ -105,9 +101,8 @@ SYM_FUNC_START(copy_user_generic_unrolled)
 	jnz 21b
 23:	xor %eax,%eax
 	ASM_CLAC
-	ret
+	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
+	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)
 	/* CPUs without FSRM should avoid rep movsb for short copies */
 	ALTERNATIVE "cmpl $64, %edx; jb .L_copy_short_string", "", X86_FEATURE_FSRM
 	movl %edx,%ecx
-1:	rep
-	movsb
+1:	rep movsb
 	xorl %eax,%eax
 	ASM_CLAC
-	ret
+	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)
@@ -241,7 +228,7 @@ SYM_CODE_START_LOCAL(.Lcopy_user_handle_tail)
 1:	rep movsb
 2:	mov %ecx,%eax
 	ASM_CLAC
-	ret
+	RET
 
 3:
 	movl %edx,%eax
@@ -249,6 +236,11 @@ 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)
 
 /*
@@ -357,9 +349,8 @@ SYM_FUNC_START(__copy_user_nocache)
 	xorl %eax,%eax
 	ASM_CLAC
 	sfence
-	ret
+	RET
 
-	.section .fixup,"ax"
 .L_fixup_4x8b_copy:
 	shll $6,%ecx
 	addl %ecx,%edx
@@ -375,7 +366,6 @@ 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)