On Wed, Aug 21, 2019 at 04:14:53PM +0200, David Sterba wrote: > On Wed, Aug 21, 2019 at 03:24:46PM +0200, David Sterba wrote: > > On Wed, Aug 21, 2019 at 03:20:21PM +0200, David Sterba wrote: > > > On Tue, Aug 13, 2019 at 10:33:42AM -0700, Omar Sandoval wrote: > > > > From: Omar Sandoval <osandov@xxxxxx> > > > > > > > > This does some cleanups to the Btrfs workqueue code following my > > > > previous fix [1]. Changed since v1 [2]: > > > > > > > > - Removed errant Fixes: tag in patch 1 > > > > - Fixed a comment typo in patch 2 > > > > - Added NB: to comments in patch 2 > > > > - Added Nikolay and Filipe's reviewed-by tags > > > > > > > > Thanks! > > > > > > > > 1: https://lore.kernel.org/linux-btrfs/0bea516a54b26e4e1c42e6fe47548cb48cc4172b.1565112813.git.osandov@xxxxxx/ > > > > 2: https://lore.kernel.org/linux-btrfs/cover.1565680721.git.osandov@xxxxxx/ > > > > > > > > Omar Sandoval (2): > > > > Btrfs: get rid of unique workqueue helper functions > > > > Btrfs: get rid of pointless wtag variable in async-thread.c > > > > > > The patches seem to cause crashes inside the worques, happend several > > > times in random patches, sample stacktrace below. This blocks me from > > > testing so I'll move the patches out of misc-next for now and add back > > > once there's a fix. > > > > Another possibility is that the cleanup patches make it more likely to > > happen and the root cause is "Btrfs: fix workqueue deadlock on dependent > > filesystems". > > With just the deadlock fix on top<F2>, crashed in btrfs/011; > It's because we're doing wq = work->wq; after we've done set_bit(WORK_DONE_BIT, &work->flags). The work could be freed immediately after this and thus doing work->wq could give you garbage. Could you try with this diff applied and verify it goes away? diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c index 6b8ad4a1b568..10a04b99798a 100644 --- a/fs/btrfs/async-thread.c +++ b/fs/btrfs/async-thread.c @@ -252,9 +252,9 @@ static inline void thresh_exec_hook(struct __btrfs_workqueue *wq) } } -static void run_ordered_work(struct btrfs_work *self) +static void run_ordered_work(struct __btrfs_workqueue *wq, + struct btrfs_work *self) { - struct __btrfs_workqueue *wq = self->wq; struct list_head *list = &wq->ordered_list; struct btrfs_work *work; spinlock_t *lock = &wq->list_lock; @@ -356,7 +356,7 @@ static void normal_work_helper(struct btrfs_work *work) work->func(work); if (need_order) { set_bit(WORK_DONE_BIT, &work->flags); - run_ordered_work(work); + run_ordered_work(wq, work); } if (!need_order) trace_btrfs_all_work_done(wq->fs_info, wtag);
