Re: general protection fault in __handle_mm_fault

[Willem de Bruijn]

On Tue, Oct 9, 2018 at 11:00 AM Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
>
>
>
> On 10/09/2018 01:53 AM, Aneesh Kumar K.V wrote:
> ...
>
> >>>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=13cdb67e400000
> ...
>
> >
> > Can you check with this patch

Thanks. With that patch the crash indeed does not occur.

>
> Well, this is a C repro, you can test this yourself instead of asking Willem who
> already did a painful bisection.

Thanks Eric. It does take some effort to get the syzkaller environment
up and running [1] and I happen to have it ready, so I don't mind testing
a few patches.

It just had to wait until I got to the office. Somehow the debug kernel
produces so much output that it consistently locked up my shell over ssh.

[1] for reference:
https://github.com/google/syzkaller/blob/master/docs/linux/setup_ubuntu-host_qemu-vm_x86-64-kernel.md