Merge tag 'iwlwifi-for-john-2014-10-23' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / arch / x86 / ia32 / ia32entry.S

diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 4299eb0..711de08 100644 (file)
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -151,6 +151,16 @@ ENTRY(ia32_sysenter_target)
 1:     movl    (%rbp),%ebp
        _ASM_EXTABLE(1b,ia32_badarg)
        ASM_CLAC
+
+       /*
+        * Sysenter doesn't filter flags, so we need to clear NT
+        * ourselves.  To save a few cycles, we can check whether
+        * NT was set instead of doing an unconditional popfq.
+        */
+       testl $X86_EFLAGS_NT,EFLAGS(%rsp)       /* saved EFLAGS match cpu */
+       jnz sysenter_fix_flags
+sysenter_flags_fixed:
+
        orl     $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
        testl   $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
        CFI_REMEMBER_STATE
@@ -184,6 +194,8 @@ sysexit_from_sys_call:
        TRACE_IRQS_ON
        ENABLE_INTERRUPTS_SYSEXIT32
 
+       CFI_RESTORE_STATE
+
 #ifdef CONFIG_AUDITSYSCALL
        .macro auditsys_entry_common
        movl %esi,%r9d                  /* 6th arg: 4th syscall arg */
@@ -226,7 +238,6 @@ sysexit_from_sys_call:
        .endm
 
 sysenter_auditsys:
-       CFI_RESTORE_STATE
        auditsys_entry_common
        movl %ebp,%r9d                  /* reload 6th syscall arg */
        jmp sysenter_dispatch
@@ -235,6 +246,11 @@ sysexit_audit:
        auditsys_exit sysexit_from_sys_call
 #endif
 
+sysenter_fix_flags:
+       pushq_cfi $(X86_EFLAGS_IF|X86_EFLAGS_FIXED)
+       popfq_cfi
+       jmp sysenter_flags_fixed
+
 sysenter_tracesys:
 #ifdef CONFIG_AUDITSYSCALL
        testl   $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)