diff options
Diffstat (limited to 'arch/x86/kernel/entry_64.S')
| -rw-r--r-- | arch/x86/kernel/entry_64.S | 38 |
1 files changed, 20 insertions, 18 deletions
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 7d65133b51be..69babd8c834f 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -1048,24 +1048,6 @@ apicinterrupt LOCAL_TIMER_VECTOR \ apicinterrupt X86_PLATFORM_IPI_VECTOR \ x86_platform_ipi smp_x86_platform_ipi -#ifdef CONFIG_SMP - ALIGN - INTR_FRAME -.irp idx,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15, \ - 16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31 -.if NUM_INVALIDATE_TLB_VECTORS > \idx -ENTRY(invalidate_interrupt\idx) - pushq_cfi $~(INVALIDATE_TLB_VECTOR_START+\idx) - jmp .Lcommon_invalidate_interrupt0 - CFI_ADJUST_CFA_OFFSET -8 -END(invalidate_interrupt\idx) -.endif -.endr - CFI_ENDPROC -apicinterrupt INVALIDATE_TLB_VECTOR_START, \ - invalidate_interrupt0, smp_invalidate_interrupt -#endif - apicinterrupt THRESHOLD_APIC_VECTOR \ threshold_interrupt smp_threshold_interrupt apicinterrupt THERMAL_APIC_VECTOR \ @@ -1758,10 +1740,30 @@ end_repeat_nmi: */ call save_paranoid DEFAULT_FRAME 0 + + /* + * Save off the CR2 register. If we take a page fault in the NMI then + * it could corrupt the CR2 value. If the NMI preempts a page fault + * handler before it was able to read the CR2 register, and then the + * NMI itself takes a page fault, the page fault that was preempted + * will read the information from the NMI page fault and not the + * origin fault. Save it off and restore it if it changes. + * Use the r12 callee-saved register. + */ + movq %cr2, %r12 + /* paranoidentry do_nmi, 0; without TRACE_IRQS_OFF */ movq %rsp,%rdi movq $-1,%rsi call do_nmi + + /* Did the NMI take a page fault? Restore cr2 if it did */ + movq %cr2, %rcx + cmpq %rcx, %r12 + je 1f + movq %r12, %cr2 +1: + testl %ebx,%ebx /* swapgs needed? */ jnz nmi_restore nmi_swapgs: |