nvme-6.3: blktests nvme/45 lockdep warning

[Shinichiro Kawasaki]

On Jan 30, 2023 / 12:08, Daniel Wagner wrote:
> Hi,
> 
> while trying to get a baseline run with blktest against the current nvme-6.3
> branch I got a lockdep warning. I haven't really looked into it yet. I
> as that Shinichiro has fixed a bunch of those in v5.19. Thought this one
> looks slightly different.

I also observed the failure with kernel v6.2-rc6 by running the test case
nvme/045 only (I overlooked the failure since lockdep was disabled by by other
lockdep WARNs at other test cases in the same run).

I once observed this "WARNING: possible recursive locking detected" and reported
[1], while I was investigating the "bad unlock balance" issue which Sagi fixed.

[1] https://lore.kernel.org/linux-nvme/20221026120150.luck4dinfvhrw7se@shindev/

I think the cause of the WARN is that ctrl->dhchap_auth_work flushes
chap->auth_work but these two works are queued in the same queue. I created a
patch to add another queue dedicated to chap->auth_work. With the patch, I
observed the WARN is avoided. Will post it to ask comments.

-- 
Shin'ichiro Kawasaki