Re: general protection fault in mas_empty_area_rev

From: Marius Fleischer
Date: Mon Apr 22 2024 - 14:07:43 EST


Hi Liam,

On Mon, 22 Apr 2024 at 10:05, Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> wrote:
> * Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> [240422 11:25]:
> > * Marius Fleischer <fleischermarius@xxxxxxxxx> [240422 11:11]:
> > > Hi Liam,
> > >
> > > Thank you so much for the response!
> > >
> > > > >
> > > > > Crash log:
> > > > >
> > > > > general protection fault, probably for non-canonical address
> > > > > 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI
> > > > >
> > > > > KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
> > > > >
> > > > > CPU: 0 PID: 79545 Comm: syz-executor.0 Not tainted 6.9.0-rc4-dirty #3
> > > >
> > > > This indicates that you built with your own patches. Could you test an
> > > > unmodified 6.9.0-rc4 with your setup?
> > > >
> > >
> > > I'm very sorry for this oversight. I had applied the patches for another bug
> > > from this conversation
> > > (https://lore.kernel.org/all/20240404070702.2744-3-osalvador@xxxxxxx/T/#m480f21ab850996395082d0faab7f624f45b83781)
> > > I will test the reproducer without these patches and get back to you!
> >
> > After testing with your config, I can see that those fixes are needed to
> > boot.
> >
> > I am going to try 6.9-rc5 with your configuration and see if I can
> > trigger the issue there.
> >
>
> The reproducer does not trigger for me with your configuration and
> reproducer.
>
> Does it still happen for you in 6.9-rc5?
>
You are right, indeed, I was not able to boot v6.9-rc4 without the fixes.

I tested the reproducer on 6.9-rc5 (ed30a4a51bb196781c8058073ea720133a65596f)
and it still triggers the crash in my setup. How can I help you
further troubleshoot
this issue?

Thanks,
Marius