From nobody Mon Sep 16 20:23:51 2024 Delivered-To: importer2@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer2=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1712735029186257.5026159376026; Wed, 10 Apr 2024 00:43:49 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ruSNr-0005v1-Vm; Wed, 10 Apr 2024 03:28:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ruSNq-0005hW-Hr; Wed, 10 Apr 2024 03:28:38 -0400 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ruSNn-0004uq-Oa; Wed, 10 Apr 2024 03:28:38 -0400 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id A02C35D6A9; Wed, 10 Apr 2024 10:25:06 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id 44083B02E9; Wed, 10 Apr 2024 10:23:08 +0300 (MSK) Received: (nullmailer pid 4191820 invoked by uid 1000); Wed, 10 Apr 2024 07:23:04 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Fiona Ebner , Kevin Wolf , Stefan Hajnoczi , Michael Tokarev Subject: [Stable-8.2.3 57/87] block-backend: fix edge case in bdrv_next_cleanup() where BDS associated to BB changes Date: Wed, 10 Apr 2024 10:22:30 +0300 Message-Id: <20240410072303.4191455-57-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer2=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer2=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer2=patchew.org@nongnu.org X-ZM-MESSAGEID: 1712735030985100007 Content-Type: text/plain; charset="utf-8" From: Fiona Ebner Same rationale as for commit "block-backend: fix edge case in bdrv_next() where BDS associated to BB changes". The block graph might change between the bdrv_next() call and the bdrv_next_cleanup() call, so it could be that the associated BDS is not the same that was referenced previously anymore. Instead, rely on bdrv_next() to set it->bs to the BDS it referenced and unreference that one in any case. Signed-off-by: Fiona Ebner Message-ID: <20240322095009.346989-4-f.ebner@proxmox.com> Reviewed-by: Kevin Wolf Reviewed-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf (cherry picked from commit bac09b093ebbb79e6a7444c7b979c32ca5540132) Signed-off-by: Michael Tokarev diff --git a/block/block-backend.c b/block/block-backend.c index 4a419f75fb..86315d62c6 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -677,13 +677,10 @@ void bdrv_next_cleanup(BdrvNextIterator *it) /* Must be called from the main loop */ assert(qemu_get_current_aio_context() =3D=3D qemu_get_aio_context()); =20 - if (it->phase =3D=3D BDRV_NEXT_BACKEND_ROOTS) { - if (it->blk) { - bdrv_unref(blk_bs(it->blk)); - blk_unref(it->blk); - } - } else { - bdrv_unref(it->bs); + bdrv_unref(it->bs); + + if (it->phase =3D=3D BDRV_NEXT_BACKEND_ROOTS && it->blk) { + blk_unref(it->blk); } =20 bdrv_next_reset(it); --=20 2.39.2