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    SubjectRe: [PATCH] x86/entry/64: Fix native_load_gs_index() SWAPGS handling with IRQ state tracing enabled
    On Wed, Nov 29, 2017 at 08:09:51AM +0100, Ingo Molnar wrote:
    > diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
    > index f81d50d7ceac..c0b52df8ee4f 100644
    > --- a/arch/x86/entry/entry_64.S
    > +++ b/arch/x86/entry/entry_64.S
    > @@ -945,16 +945,16 @@ idtentry simd_coprocessor_error do_simd_coprocessor_error has_error_code=0
    > */
    > ENTRY(native_load_gs_index)
    > FRAME_BEGIN
    > + SWAPGS /* switch from user GS to kernel GS */
    > pushfq
    > DISABLE_INTERRUPTS(CLBR_ANY & ~CLBR_RDI)
    > TRACE_IRQS_OFF
    > - SWAPGS

    I'm thinking those moves it too far back; we should at least have
    interrupts disabled when we do SWAPGS, no? Also, curse paravirt.

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