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[79.181.91.42]) by smtp.gmail.com with ESMTPSA id q17sm40074395qtl.13.2019.08.10.12.12.14 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Sat, 10 Aug 2019 12:12:16 -0700 (PDT) Date: Sat, 10 Aug 2019 15:12:11 -0400 From: "Michael S. Tsirkin" To: Jason Wang Cc: Jason Gunthorpe , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH V5 0/9] Fixes for vhost metadata acceleration Message-ID: <20190810150611-mutt-send-email-mst@kernel.org> References: <20190807070617.23716-1-jasowang@redhat.com> <20190807070617.23716-8-jasowang@redhat.com> <20190807120738.GB1557@ziepe.ca> <1000f8a3-19a9-0383-61e5-ba08ddc9fcba@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1000f8a3-19a9-0383-61e5-ba08ddc9fcba@redhat.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Aug 08, 2019 at 08:54:54PM +0800, Jason Wang wrote: > I don't have any objection to convert  to spinlock() but just want to > know if any case that the above smp_mb() + counter looks good to you? So how about we try this: - revert the original patch for this release - new safe patch with a spinlock for the next release - whatever improvements we can come up with on top Thoughts? Because I think this needs much more scrutiny than we can give an incremental patch. -- MST