diff options
| author | Andy Lutomirski <[email protected]> | 2015-07-15 10:29:34 -0700 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2015-07-17 12:50:11 +0200 |
| commit | 0e181bb58143cb4a2e8f01c281b0816cd0e4798e (patch) | |
| tree | 14eb4bb8ddec0622dc8123f744f893d14b09cdb5 | |
| parent | 9d05041679904b12c12421cbcf9cb5f4860a8d7b (diff) | |
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 <[email protected]>
Reviewed-by: Steven Rostedt <[email protected]>
Acked-by: Borislav Petkov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/entry/entry_64.S | 17 |
1 files changed, 0 insertions, 17 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 3bb2c4302df1..062feb4eb478 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: |