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Subject: Re: panic: wm_page_unwire
From: Dmitry Sivachenko <trtrmitya@gmail.com>
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Date: Sat, 20 Jun 2015 14:07:51 +0300
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To: Konstantin Belousov <kostikbel@gmail.com>
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> On 20 =C9=C0=CE=D1 2015 =C7., at 13:01, Konstantin Belousov =
<kostikbel@gmail.com> wrote:
>=20
>=20
> I was able to reproduce something related, this may be very well your
> problem.  Take the attached program.  Select a scratch file on UFS =
mount
> point, say x.  Run the following commands:
> mlock_modify x&
> dd if=3D/dev/zero of=3Dx bs=3D1 count=3D1
> fg
> ^C <- system might panic at this point, if buffers are in short supply
> dd if=3D/dev/zero of=3Dx bs=3D1 count=3D1 <- at this point, the system =
must panic


Yes, that is exactly two cases when I was able to reproduce a panic, so =
it is apparently my issue.

I tried your patch and I can confirm that it does fix the problem.

Thanks!