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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 18 Aug 2020 12:01:43 -0700
Message-ID: <CAHk-=wjbaptBBKYS+XdCgdjU_RbFPaAd8EkT6_Un6CtNmezt9A@mail.gmail.com>
Subject: Re: [v3 PATCH] mm/memory.c: skip spurious TLB flush for retried page fault
To:     Yang Shi <shy828301@gmail.com>
Cc:     Yu Xu <xuyu@linux.alibaba.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux-MM <linux-mm@kvack.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        stable <stable@vger.kernel.org>
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On Mon, Aug 17, 2020 at 2:04 PM Yang Shi <shy828301@gmail.com> wrote:
>
> We could just skip the spurious TLB flush to mitigate the regression.

Ok, this patch I will apply.

I still hope that arm64 fixes (maybe already fixed) their spurious TLB
function, and I think we should rename it to make sure everybody
understands it's local, but in the meantime this patch hides the
regression and isn't wrong.

Thanks,

                Linus