Re: [PATCH v4 0/4] btrf_show_devname related fixes

On Wed, Aug 25, 2021 at 10:13:52AM +0800, Anand Jain wrote:

On 25/08/2021 00:11, David Sterba wrote:

quoted

On Tue, Aug 24, 2021 at 08:28:09AM +0800, Anand Jain wrote:

quoted

On 24/08/2021 03:46, David Sterba wrote:

quoted

On Mon, Aug 23, 2021 at 07:31:38PM +0800, Anand Jain wrote:

quoted

These fixes are inspired by the bug report and its discussions in the
mailing list subject
   btrfs: traverse seed devices if fs_devices::devices is empty in show_devname

And depends on the patch
   [PATCH v2] btrfs: fix lockdep warning while mounting sprout fs
in the ML

v4:
   Fix unrelated changes in 2/4
v3:
   Fix rcu_lock in the patch 3/4

Anand Jain (4):
    btrfs: consolidate device_list_mutex in prepare_sprout to its parent
    btrfs: save latest btrfs_device instead of its block_device in
      fs_devices
    btrfs: use latest_dev in btrfs_show_devname
    btrfs: update latest_dev when we sprout

Patchset survived one round of fstests and I haven't seen the lockdep
warning in btrfs/020 that's caused by some unrelated work in loop device
driver.

quoted

There's a series from Josef to fix it by shuffling locking,

   Hm. Is it a recent patch? I can't find.

https://lore.kernel.org/linux-btrfs/cover.1627419595.git.josef@toxicpanda.com/ (local)

Thx.
It is the same fix I sent ~3months before in the ML[1].

Well, I've seen the patch and pings but sometimes the timing is not good
and there's something else I have to finish before looking into new
area. And device locking is something that needs full attention. The
bugs/warnings in question weren't that important.

But anyway now the 5.15 branch is out and there are several patches
regarding the devices so I'm going to spend time on that.  Also because
the recent updates to loop devices started to trigger lockdep warnings
that make testing harder and we're missing lockdep in many tests.