On 4/27/18 4:48 AM, Filipe Manana wrote: > On Thu, Apr 26, 2018 at 8:23 PM, <je...@suse.com> wrote: >> From: Jeff Mahoney <je...@suse.com> >> >> Commit d2c609b834d6 (Btrfs: fix qgroup rescan worker initialization) >> fixed the issue with BTRFS_IOC_QUOTA_RESCAN_WAIT being racy, but >> ended up reintroducing the hang-on-unmount bug that the commit it >> intended to fix addressed. >> >> The race this time is between qgroup_rescan_init setting >> ->qgroup_rescan_running = true and the worker starting. There are >> many scenarios where we initialize the worker and never start it. The >> completion btrfs_ioctl_quota_rescan_wait waits for will never come. >> This can happen even without involving error handling, since mounting >> the file system read-only returns between initializing the worker and >> queueing it. >> >> The right place to do it is when we're queuing the worker. The flag >> really just means that btrfs_ioctl_quota_rescan_wait should wait for >> a completion. >> >> This patch introduces a new helper, queue_rescan_worker, that handles >> the ->qgroup_rescan_running flag, including any races with umount. >> >> While we're at it, ->qgroup_rescan_running is protected only by the >> ->qgroup_rescan_mutex. btrfs_ioctl_quota_rescan_wait doesn't need >> to take the spinlock too. >> >> Fixes: d2c609b834d6 (Btrfs: fix qgroup rescan worker initialization) > > The commit id and subjects don't match: > > commit d2c609b834d62f1e91f1635a27dca29f7806d3d6 > Author: Jeff Mahoney <je...@suse.com> > Date: Mon Aug 15 12:10:33 2016 -0400 > > btrfs: properly track when rescan worker is running >
Thanks. Fixed. -Jeff -- Jeff Mahoney SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
