{"id":2229019,"url":"http://patchwork.ozlabs.org/api/1.1/covers/2229019/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/cover/20260427170520.101242-1-kwolf@redhat.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.1/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260427170520.101242-1-kwolf@redhat.com>","date":"2026-04-27T17:05:16","name":"[0/4] qcow2: Fix corruption on discard during write with COW","submitter":{"id":2714,"url":"http://patchwork.ozlabs.org/api/1.1/people/2714/?format=json","name":"Kevin Wolf","email":"kwolf@redhat.com"},"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/cover/20260427170520.101242-1-kwolf@redhat.com/mbox/","series":[{"id":501688,"url":"http://patchwork.ozlabs.org/api/1.1/series/501688/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=501688","date":"2026-04-27T17:05:16","name":"qcow2: Fix corruption on discard during write with COW","version":1,"mbox":"http://patchwork.ozlabs.org/series/501688/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/covers/2229019/comments/","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=NUKfexdq;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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Mon, 27 Apr 2026 13:05:45 -0400","from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com\n (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by\n relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3,\n cipher=TLS_AES_256_GCM_SHA384) id us-mta-421-K8iLuBRbM_2UTbEIT5v4CA-1; Mon,\n 27 Apr 2026 13:05:40 -0400","from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com\n (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111])\n (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest\n SHA256)\n (No client certificate requested)\n by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS\n id 2C72B19560AB; Mon, 27 Apr 2026 17:05:39 +0000 (UTC)","from merkur.fritz.box (unknown [10.44.49.22])\n by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP\n id D1838180047F; Mon, 27 Apr 2026 17:05:36 +0000 (UTC)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;\n s=mimecast20190719; t=1777309543;\n h=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n to:to:cc:cc:mime-version:mime-version:\n content-transfer-encoding:content-transfer-encoding;\n bh=zGre//01tH2c35nomgMy5ZkAJ2hN3fs8V+xTYufnCEk=;\n b=NUKfexdqVSnxQEqtBawLcpNUAIBkqthjmZ++0v70OQRrCKBlx5Z1drY//MYeZzeknR1aGc\n NOwUX70kLmFDxqomUu9cJsi9SXmRRRIlnfePrsyxxYMOHW2nTPGV36H6v8vq2hPh/KOJ0i\n phzEMUddlgs85UwH2RMxpj+gJcO1MEg=","X-MC-Unique":"K8iLuBRbM_2UTbEIT5v4CA-1","X-Mimecast-MFC-AGG-ID":"K8iLuBRbM_2UTbEIT5v4CA_1777309539","From":"Kevin Wolf ","To":"qemu-block@nongnu.org","Cc":"kwolf@redhat.com, hreitz@redhat.com, den@openvz.org, stefanha@redhat.com,\n qemu-stable@nongnu.org, qemu-devel@nongnu.org","Subject":"[PATCH 0/4] qcow2: Fix corruption on discard during write with COW","Date":"Mon, 27 Apr 2026 19:05:16 +0200","Message-ID":"<20260427170520.101242-1-kwolf@redhat.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Scanned-By":"MIMEDefang 3.4.1 on 10.30.177.111","Received-SPF":"pass client-ip=170.10.129.124; envelope-from=kwolf@redhat.com;\n helo=us-smtp-delivery-124.mimecast.com","X-Spam_score_int":"-20","X-Spam_score":"-2.1","X-Spam_bar":"--","X-Spam_report":"(-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001,\n DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001,\n SPF_HELO_PASS=-0.001,\n SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no","X-Spam_action":"no action","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"This is an alternative fix for the corruption problem reported by Denis:\nhttps://patchew.org/QEMU/20260421155628.3600671-1-den@openvz.org/\n\nI think it really is a qcow2 level bug and should be fixed on the qcow2\nlevel. The test is also more targeted than just doing random I/O for a\nwhile, and therefore runs faster and documents the problem better.\n\nKevin Wolf (4):\n commit: Drain nodes across all of bdrv_commit()\n qemu-io: Add 'aio_discard' command\n qcow2: Fix corruption on discard during write with COW\n iotests/046: Test that discard/write_zeroes wait for dependencies\n\n block/commit.c | 10 +++-\n block/qcow2-cluster.c | 52 ++++++++++++++++-\n qemu-io-cmds.c | 113 +++++++++++++++++++++++++++++++++++++\n tests/qemu-iotests/046 | 46 +++++++++++++++\n tests/qemu-iotests/046.out | 36 ++++++++++++\n 5 files changed, 252 insertions(+), 5 deletions(-)"}