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Date:   Thu, 24 Oct 2019 20:09:40 -0700 (PDT)
From:   Paul Walmsley <paul.walmsley@sifive.com>
To:     Atish Patra <atish.patra@wdc.com>
cc:     linux-kernel@vger.kernel.org, Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv@lists.infradead.org,
        Palmer Dabbelt <palmer@sifive.com>,
        Christoph Hellwig <hch@lst.de>, Anup Patel <Anup.Patel@wdc.com>
Subject: Re: [PATCH v4 0/3] Optimize tlbflush path
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On Fri, 30 Aug 2019, Paul Walmsley wrote:

> On Thu, 22 Aug 2019, Atish Patra wrote:
> 
> > This series adds few optimizations to reduce the trap cost in the tlb
> > flush path. We should only make SBI calls to remote tlb flush only if
> > absolutely required. 
> 
> The patches look great.  My understanding is that these optimization 
> patches may actually be a partial workaround for the TLB flushing bug that 
> we've been looking at for the last month or so, which can corrupt memory 
> or crash the system.

I don't think we're any closer to root-causing this issue.  Meanwhile, 
OpenSBI has merged patches to work around it.  So since many of us have 
looked at Atish's TLB optimization patches, and we all think they are 
useful optimizations, let's plan to merge it for v5.5-rc1.


- Paul