From owner-svn-src-stable@freebsd.org Mon Apr 16 04:11:49 2018 Return-Path: Delivered-To: svn-src-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 40977F83832; Mon, 16 Apr 2018 04:11:49 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id E2B266AA4D; Mon, 16 Apr 2018 04:11:48 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id DD4651854E; Mon, 16 Apr 2018 04:11:48 +0000 (UTC) (envelope-from mav@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id w3G4Bmcq030371; Mon, 16 Apr 2018 04:11:48 GMT (envelope-from mav@FreeBSD.org) Received: (from mav@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w3G4BmWs030370; Mon, 16 Apr 2018 04:11:48 GMT (envelope-from mav@FreeBSD.org) Message-Id: <201804160411.w3G4BmWs030370@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mav set sender to mav@FreeBSD.org using -f From: Alexander Motin Date: Mon, 16 Apr 2018 04:11:48 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r332548 - stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs X-SVN-Group: stable-11 X-SVN-Commit-Author: mav X-SVN-Commit-Paths: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs X-SVN-Commit-Revision: 332548 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Apr 2018 04:11:49 -0000 Author: mav Date: Mon Apr 16 04:11:48 2018 New Revision: 332548 URL: https://svnweb.freebsd.org/changeset/base/332548 Log: MFC r331703: MFV 331702: 9187 racing condition between vdev label and spa_last_synced_txg in vdev_validate illumos/illumos-gate@d1de72cfa29ab77ff80e2bb0e668a6afa5bccaf0 ztest failed with uncorrectable IO error despite having the fix for #7163. Both sides of the mirror have CANT_OPEN_BAD_LABEL, which also distinguishes it from that issue. Definitely seems like a racing condition between the vdev_validate and spa_sync: 1. Thread A (spa_sync): vdev label is updated to latest txg 2. Thread B (vdev_validate): vdev label's txg is compared to spa_last_synced_txg and is ahead. 3. Thread A (spa_sync): spa_last_synced_txg is updated to latest txg. Solution: do not check txg in vdev_validate unless config lock is held. Reviewed by: George Wilson Reviewed by: Matt Ahrens Approved by: Robert Mustacchi Author: Pavel Zakharov Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c ============================================================================== --- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c Mon Apr 16 04:10:56 2018 (r332547) +++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c Mon Apr 16 04:11:48 2018 (r332548) @@ -1696,8 +1696,11 @@ vdev_validate(vdev_t *vd) /* * If we are performing an extreme rewind, we allow for a label that * was modified at a point after the current txg. + * If config lock is not held do not check for the txg. spa_sync could + * be updating the vdev's label before updating spa_last_synced_txg. */ - if (spa->spa_extreme_rewind || spa_last_synced_txg(spa) == 0) + if (spa->spa_extreme_rewind || spa_last_synced_txg(spa) == 0 || + spa_config_held(spa, SCL_CONFIG, RW_WRITER) != SCL_CONFIG) txg = UINT64_MAX; else txg = spa_last_synced_txg(spa);