From: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Date: Thu, 21 Apr 2022 22:10:51 +0800
Subject: x86/entry: Move CLD to the start of the idtentry macro
Git-commit: c64cc2802a784ecfd25d39945e57e7a147854a5b
Patch-mainline: 5.19-rc1
References: git-fixes
Move it after CLAC.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220503032107.680190-5-jiangshanlai@gmail.com
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/x86/entry/entry_64.S | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -364,6 +364,7 @@ SYM_CODE_END(push_and_clear_regs)
SYM_CODE_START(\asmsym)
UNWIND_HINT_IRET_REGS offset=\has_error_code*8
ASM_CLAC
+ cld
.if \has_error_code == 0
pushq $-1 /* ORIG_RAX: no syscall to restart */
@@ -431,6 +432,7 @@ SYM_CODE_END(\asmsym)
SYM_CODE_START(\asmsym)
UNWIND_HINT_IRET_REGS
ASM_CLAC
+ cld
pushq $-1 /* ORIG_RAX: no syscall to restart */
@@ -486,6 +488,7 @@ SYM_CODE_END(\asmsym)
SYM_CODE_START(\asmsym)
UNWIND_HINT_IRET_REGS
ASM_CLAC
+ cld
/*
* If the entry is from userspace, switch stacks and treat it as
@@ -548,6 +551,7 @@ SYM_CODE_END(\asmsym)
SYM_CODE_START(\asmsym)
UNWIND_HINT_IRET_REGS offset=8
ASM_CLAC
+ cld
/* paranoid_entry returns GS information for paranoid_exit in EBX. */
call paranoid_entry
@@ -862,7 +866,6 @@ SYM_CODE_END(xen_failsafe_callback)
*/
SYM_CODE_START_LOCAL(paranoid_entry)
UNWIND_HINT_FUNC
- cld
PUSH_AND_CLEAR_REGS save_ret=1
ENCODE_FRAME_POINTER 8
@@ -980,7 +983,6 @@ SYM_CODE_END(paranoid_exit)
*/
SYM_CODE_START_LOCAL(error_entry)
UNWIND_HINT_FUNC
- cld
testb $3, CS+8(%rsp)
jz .Lerror_kernelspace
@@ -1113,6 +1115,7 @@ SYM_CODE_START(asm_exc_nmi)
*/
ASM_CLAC
+ cld
/* Use %rdx as our temp variable throughout */
pushq %rdx
@@ -1132,7 +1135,6 @@ SYM_CODE_START(asm_exc_nmi)
*/
swapgs
- cld
FENCE_SWAPGS_USER_ENTRY
SWITCH_TO_KERNEL_CR3 scratch_reg=%rdx
movq %rsp, %rdx