diff options
Diffstat (limited to 'arch/x86/entry/entry_64_compat.S')
| -rw-r--r-- | arch/x86/entry/entry_64_compat.S | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index 3c990eeee40b..da5c19443e0b 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -66,8 +66,6 @@ ENTRY(entry_SYSENTER_compat) */ pushfq /* pt_regs->flags (except IF = 0) */ orl $X86_EFLAGS_IF, (%rsp) /* Fix saved flags */ - ASM_CLAC /* Clear AC after saving FLAGS */ - pushq $__USER32_CS /* pt_regs->cs */ xorq %r8,%r8 pushq %r8 /* pt_regs->ip = 0 (placeholder) */ @@ -90,9 +88,9 @@ ENTRY(entry_SYSENTER_compat) cld /* - * Sysenter doesn't filter flags, so we need to clear NT + * SYSENTER doesn't filter flags, so we need to clear NT and AC * ourselves. To save a few cycles, we can check whether - * NT was set instead of doing an unconditional popfq. + * either was set instead of doing an unconditional popfq. * This needs to happen before enabling interrupts so that * we don't get preempted with NT set. * @@ -102,7 +100,7 @@ ENTRY(entry_SYSENTER_compat) * we're keeping that code behind a branch which will predict as * not-taken and therefore its instructions won't be fetched. */ - testl $X86_EFLAGS_NT, EFLAGS(%rsp) + testl $X86_EFLAGS_NT|X86_EFLAGS_AC, EFLAGS(%rsp) jnz .Lsysenter_fix_flags .Lsysenter_flags_fixed: |