Re: [syzbot] [mm?] possible deadlock in __vma_start_write

From: Lorenzo Stoakes
Date: Wed Jun 04 2025 - 01:18:29 EST


On Tue, Jun 03, 2025 at 05:51:41PM -0700, Suren Baghdasaryan wrote:
> On Mon, Jun 2, 2025 at 7:19 AM Lorenzo Stoakes
> <lorenzo.stoakes@xxxxxxxxxx> wrote:
> >
> > On Mon, Jun 02, 2025 at 07:16:40AM -0700, Suren Baghdasaryan wrote:
> > > On Mon, Jun 2, 2025 at 6:04 AM Lorenzo Stoakes
> > > <lorenzo.stoakes@xxxxxxxxxx> wrote:
> > > >
> > > > +cc Suren
> > > >
> > > > Suren - could you take a look at this please?
> > >
> > > Sure. I'll take a look today or tomorrow once I sort out my email
> > > backlog. I was away for 10 days and have 2K emails to go through.
> > >
> >
>
> I spent some time trying to connect the dots and still don't have the
> definitive answer. I'll dive into it again tomorrow and post once I
> have something useful.
> Thanks,
> Suren.

Thanks for taking a look! This is a tricky one as non-repro, etc. I suspect a
very short race window somewhere.

>
> > Oh man and I thought my inbox was bad :) Sorry to add to it!
> >
> > No pressure, just a weird locking case, I'm wondering if there's something
> > here or we just need to teach lockdep that this situation is ok.
> >
> > Hope you had some nice time away anyway :)
> >
> > Cheers, Lorenzo