Re: xfs : WARNING: possible circular locking dependency detected

From: Andrey Ryabinin
Date: Thu Apr 18 2024 - 10:00:59 EST


On Thu, Apr 18, 2024 at 8:56 AM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote:
>
> Adding the KASAN maintainer so that we actuall have a chane of
> fixing this instead of a rant that just gets lost on the xfs list..
>

Thanks.

> On Thu, Apr 18, 2024 at 03:04:24PM +1000, Dave Chinner wrote:
> > The only krealloc() in this path is:
> >
> > new = krealloc(ifp->if_data, new_size,
> > GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
> >
> > And it explicitly uses __GFP_NOLOCKDEP to tell lockdep not to warn
> > about this allocation because of this false positive situation.
> >
> > Oh. I've seen this before. This is a KASAN bug, and I'm pretty sure
> > I've posted a patch to fix it a fair while back that nobody seemed
> > to care about enough to review or merge it.
> >

Sorry, must have been my bad. I didn't find the actual patch though,
only proposed way to fix this bug:
https://lkml.kernel.org/r/%3C20230119045253.GI360264@xxxxxxxxxxxxxxxxxxx%3E
So I'll cook patch and will send it shortly.