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    SubjectRe: [PATCH 1/2] x86/kasan: clear kasan_zero_page after TLB flush
    On Mon, Jan 11, 2016 at 4:51 AM, Andrey Ryabinin
    <aryabinin@virtuozzo.com> wrote:
    > Currently we clear kasan_zero_page before __flush_tlb_all(). This
    > works with current implementation of native_flush_tlb[_global]()
    > because it doesn't cause do any writes to kasan shadow memory.
    > But any subtle change made in native_flush_tlb*() could break this.
    > Also current code seems doesn't work for paravirt guests (lguest).
    >
    > Only after the TLB flush we can be sure that kasan_zero_page is not
    > used as early shadow anymore (instrumented code will not write to it).
    > So it should cleared it only after the TLB flush.

    This seems to fix the issue with my patch set. Thanks.

    Tested-by: Andy Lutomirski <luto@kernel.org>

    --Andy

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