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From:   Nadav Amit <namit@vmware.com>
To:     Dave Hansen <dave.hansen@linux.intel.com>
CC:     LKML <linux-kernel@vger.kernel.org>,
        Hugh Dickins <hughd@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        X86 ML <x86@kernel.org>, Linux MM <linux-mm@kvack.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        Nadav Amit <nadav.amit@gmail.com>
Subject: Re: [PATCH v2] x86/mm/tlb: ignore f->new_tlb_gen when zero
Thread-Topic: [PATCH v2] x86/mm/tlb: ignore f->new_tlb_gen when zero
Thread-Index: AQHYlPRIBVYGglwRp0y21cAEvAmJeq15cHiA
Date:   Mon, 11 Jul 2022 17:39:37 +0000
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References: <20220710232837.3618-1-namit@vmware.com>
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On Jul 10, 2022, at 4:28 PM, Nadav Amit <nadav.amit@gmail.com> wrote:

> From: Nadav Amit <namit@vmware.com>
>=20
> Commit aa44284960d5 ("x86/mm/tlb: Avoid reading mm_tlb_gen when
> possible") introduced an optimization of skipping the flush if the TLB
> generation that is flushed (as provided in flush_tlb_info) was already
> flushed.

Dave,

Can you please review this patch today?

I feel bad (for a good reason) for breaking swap/migration.

Thanks,
Nadav