Unverified Commit 7c32c286 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!12767 x86/bugs: Use code segment selector for VERW operand 

Merge Pull Request from: @ci-robot 
 
PR sync from: Xiongfeng Wang <wangxiongfeng2@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/RGXMA3AVMMOWUK5Q2W7HHUNSJ43NAI5N/ 
 
https://gitee.com/src-openeuler/kernel/issues/IB0EMW 
 
Link:https://gitee.com/openeuler/kernel/pulls/12767

 

Reviewed-by: default avatarXie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: default avatarZhang Peng <zhangpeng362@huawei.com>
parents 42a01c6d d6ed7123

arch/x86/include/asm/nospec-branch.h

+10 −1
Original line number Diff line number Diff line
@@ -332,7 +332,16 @@ 
 * Note: Only the memory operand variant of VERW clears the CPU buffers.

 */

.macro CLEAR_CPU_BUFFERS

	ALTERNATIVE "", __stringify(verw _ASM_RIP(mds_verw_sel)), X86_FEATURE_CLEAR_CPU_BUF

#ifdef CONFIG_X86_64

	ALTERNATIVE "", "verw mds_verw_sel(%rip)", X86_FEATURE_CLEAR_CPU_BUF

#else

	/*

	 * In 32bit mode, the memory operand must be a %cs reference. The data

	 * segments may not be usable (vm86 mode), and the stack segment may not

	 * be flat (ESPFIX32).

	 */

	ALTERNATIVE "", "verw %cs:mds_verw_sel", X86_FEATURE_CLEAR_CPU_BUF

#endif

.endm



#ifdef CONFIG_X86_64