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([2001:b07:6468:f312:9c71:ae6b:ee1c:2d9e]) by smtp.gmail.com with ESMTPSA id u17sm7518267wmu.31.2020.04.08.08.05.24 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 08 Apr 2020 08:05:24 -0700 (PDT) Subject: Re: [RFC PATCH 0/4] async: fix hangs on weakly-ordered architectures To: Ying Fang , qemu-devel@nongnu.org References: <20200407140746.8041-1-pbonzini@redhat.com> <047d4327-8a79-ffc1-94fe-47355ed955c5@huawei.com> From: Paolo Bonzini Message-ID: <13f3affe-0c08-476d-e85c-2a3826b5dc1c@redhat.com> Date: Wed, 8 Apr 2020 17:05:21 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <047d4327-8a79-ffc1-94fe-47355ed955c5@huawei.com> Content-Language: en-US X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: stefanha@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 08/04/20 11:12, Ying Fang wrote: > On 2020/4/7 22:07, Paolo Bonzini wrote: >> ARM machines and other weakly-ordered architectures have been suffering >> for a long time from hangs in qemu-img and qemu-io.=C2=A0 For QEMU binar= ies >> these are mitigated by the timers that sooner or later fire in the main >> loop, but these will not happen for the tools and probably not with I/O >> threads either. > > yes, we occasionally see qemu main thread hangs and VM stuck in in-shutdo= wn > state on aarch64 platform. So this could happen with I/O threads. Thanks for confirming! Have you managed to test the final version of the patches? It would be great to include test results. Paolo