On Thu, Jan 17, 2019 at 09:04:13AM +0800, Qu Wenruo wrote: > > > On 2019/1/17 上午12:00, Josef Bacik wrote: > > qgroups will do the old roots lookup at delayed ref time, which could be > > while walking down the extent root while running a delayed ref. This > > should be fine, except we specifically lock eb's in the backref walking > > code irrespective of path->skip_locking, which deadlocks the system. > > Fix up the backref code to honor path->skip_locking, nobody will be > > modifying the commit_root when we're searching so it's completely safe > > to do. Thanks, > > > > Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx> > > Reviewed-by: Qu Wenruo <wqu@xxxxxxxx> What can we use from https://patchwork.kernel.org/patch/10725371/ to add to the changelog? Is the deadlock caused by fb235dc06fac? The fix applies to stable 4.19+ directly and to 4.14 with context fixups. Thanks.
