Re: [syzbot] [mm?] [fs?] BUG: sleeping function called from invalid context in folio_mc_copy

[Luis Chamberlain]

On Thu, Mar 27, 2025 at 09:26:41AM -0700, syzbot wrote:
> Hello,

Thanks, this is a known issue and we're having a hard time reproducing [0].

> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=152d4de4580000

Thanks! Sadly this has not yet been able to let me reprodouce the issue,
and so we're trying to come up with other ways to test the imminent spin
lock + sleep on buffer_migrate_folio_norefs() path different ways now,
including a new fstests [1] but no luck yet.

We will work on a fix, let's follow up on the original report [0] or the new
tests case suggested thread [1] thanks!

[0] https://lkml.kernel.org/r/202503101536.27099c77-lkp@xxxxxxxxx                    
[1] https://lkml.kernel.org/r/0250326185101.2237319-1-mcgrof@xxxxxxxxxx

  Luis