Re: [PATCH v2 0/3] btrfs: fix problem with balance recovery and snap delete

[David Sterba <dsterba@suse.cz>]

On Mon, Feb 21, 2022 at 05:20:32PM +0100, David Sterba wrote:
> On Fri, Feb 18, 2022 at 02:56:09PM -0500, Josef Bacik wrote:
> > v1->v2:
> > - reworked the fix based on Filipe's feedback.  Instead of just doing all the
> >   snapshot delete at mount time simply keep track of any in-progress drops.
> >   Then gate relocation on those drops finishing.  Once the drops finish we
> >   unblock relocation and carry on like normal.
> > 
> > --- Original email ---
> > Hello,
> > 
> > I found a problem where we'll try to add refs to blocks that no longer have
> > references because we started a relocation while we had a half deleted snapshot
> > in the file system.  This only occurs on a clean mount with a pending snapshot
> > delete in place.  I saw this in production but lost the file system before I
> > could test my patch.  However I reproduced it locally with some error injection.
> > Without my patch we'd fail to run delayed refs with the warning in the commit
> > message in the first patch, with my patch we mount and can use the file system.
> > 
> > The other two patches are just cleanups that i noticed while messing with this
> > code.  Thanks,
> > 
> > Josef
> > 
> > Josef Bacik (3):
> >   btrfs: do not start relocation until in progress drops are done
> >   btrfs: use btrfs_fs_info for deleting snapshots and cleaner
> >   btrfs: pass btrfs_fs_info to btrfs_recover_relocation
> 
> Added as topic branch to for-next, thanks.

Moved to misc-next, with the clear_and_wake_up_bit fixup.