Commit-ID: 0e181bb58143cb4a2e8f01c281b0816cd0e4798e Gitweb: http://git.kernel.org/tip/0e181bb58143cb4a2e8f01c281b0816cd0e4798e Author: Andy Lutomirski <luto@xxxxxxxxxx> AuthorDate: Wed, 15 Jul 2015 10:29:34 -0700 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Fri, 17 Jul 2015 12:50:11 +0200 x86/nmi/64: Remove asm code that saves CR2 Now that do_nmi saves CR2, we don't need to save it in asm. Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx> Reviewed-by: Steven Rostedt <rostedt@xxxxxxxxxxx> Acked-by: Borislav Petkov <bp@xxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/entry/entry_64.S | 17 ----------------- 1 file changed, 17 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 3bb2c43..062feb4 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -1415,28 +1415,11 @@ end_repeat_nmi: */ call paranoid_entry - /* - * 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: -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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