K 10 svn:author V 3 mav K 8 svn:date V 27 2018-04-16T04:11:48.585745Z K 7 svn:log V 930 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 END