Re: possible deadlock in ovl_llseek 27c1936af506

From: Weiß, Simone
Date: Wed Mar 13 2024 - 11:50:29 EST


On Wed, 2024-03-13 at 15:47 +0100, Miklos Szeredi wrote:
> On Wed, 13 Mar 2024 at 14:14, Amir Goldstein <amir73il@xxxxxxxxx> wrote:
>
> > The reason for this report is calling llseek() on lower ovl from
> > ovl_copy_up_data() when ovl_copy_up_data() is called with upper
> > inode lock and the lower ovl uses the same upper fs.
> >
> > It looks to me like the possible deadlock should have been solved by commit
> > c63e56a4a652 ovl: do not open/llseek lower file with upper sb_writers held
> > that moved ovl_copy_up_data() out of the inode_lock() scope.
>
> That commit is in v6.7, so something different must be happening on v6.8-rc1.
>
> Simone, please send a new report for v6.8-rc1 if a lockdep splat can
> be reproduced on that kernel.
>
> Thanks,
> Miklos

Sure, I will try to reproduce it again and send a new report if needed.

Thanks,
Simone