Re: [PATCH 2/2] btrfs: zoned: skip reporting zone for new block group

Shinichiro Kawasaki
2025-03-13T02:24:11Z

On Mar 12, 2025 / 10:42, Damien Le Moal wrote:
> On 3/12/25 10:31, Naohiro Aota wrote:
> > There is a potential deadlock if we do report zones in an IO context. When one
> > process do a report zones and another process freezes the block device, the
> > report zones side cannot allocate a tag because the freeze is already started.
> > This can thus result in new block group creation to hang forever, blocking the
> > write path.
>
> +Shin'ichiro
>
> blktest has a failing test case due to a lockdep splat triggered by this. Would
> be good to add that information (with the splat) here.

I confirmed that this fix avoids the blktests zbd/009 failure I reported [1].
Thanks for the fix!

Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>

[1] https://lore.kernel.org/linux-block/uyijd3ufbrfbiyyaajvhyhdyytssubekvymzgyiqjqmkh33cmi@ksqjpewsqlvw/