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Sender: Guenter Roeck <groeck7@gmail.com>
Date:   Mon, 15 Aug 2022 13:38:49 -0700
From:   Guenter Roeck <linux@roeck-us.net>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     "Michael S. Tsirkin" <mst@redhat.com>,
        linux-kernel@vger.kernel.org, Greg KH <gregkh@linuxfoundation.org>
Subject: Re: upstream kernel crashes
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On Mon, Aug 15, 2022 at 11:37:54AM -0700, Linus Torvalds wrote:
> On Mon, Aug 15, 2022 at 11:22 AM Guenter Roeck <linux@roeck-us.net> wrote:
> >
> > I ended up publishing several of the syzkaller reports because I could
> > not figure out how to test the proposed patch otherwise. Sorry for the
> > noise on the mailing lists, but I just could not figure out how to
> > trigger test runs without making the reports public. Various test runs
> > are now queued. Hopefully we should get results soon.
> 
> I actually think that the best "test" is to just test the revert and
> see if the problems go away.
> 
> You may not have found a way to reliably trigger one particular
> problem, but apparently you can easily enough trigger some random
> issue with enough tests.
> 
> If it's some random memory corruption, there may simply not ba a great
> reproducer, with the oopses just depending on random layout and
> timing.
> 
... and the environment. So far we have only been able to reproduce
the problem on Google Cloud VMs (GCE), and there is seems to happen
pretty much all the time.

Guenter