Re: general protection fault in rds_ib_get_mr

From: Johannes Thumshirn
Date: Thu Jul 05 2018 - 03:06:49 EST


On Wed, Jul 04, 2018 at 05:32:20PM -0700, santosh.shilimkar@xxxxxxxxxx wrote:
> On 7/4/18 2:35 PM, Eric Biggers wrote:
> > On Sun, May 13, 2018 at 10:46:37PM -0700, santosh.shilimkar@xxxxxxxxxx wrote:
> > > On 5/13/18 2:10 PM, Eric Biggers wrote:
> > > > On Wed, Mar 21, 2018 at 09:00:01AM -0700, syzbot wrote:
> > >
> > > [...]
> > >
> > >
> > > > Still reproducible on Linus' tree (commit 66e1c94db3cd4) and linux-next
> > > > (next-20180511). Here's a simplified reproducer:
> > > >
> > > Thanks for the test case !!
> > >
>
> [...]
>
> >
> > Ping; this RDS bug is still unfixed. The same reproducer I gave earlier still
> > works, even when run as a non-root user. I tested upstream commit
> > fc36def997cfd6 (v4.18-rc3-113-gfc36def997cfd), and linux-next commit
> > bce40927669338 (next-20180704).
> >
> Yeah I haven't sent a fix for this yet. Downstream we have refactored
> MR code and I wanted to get that upstream. With that this bug will
> also get addressed. I was hoping to get that series but since some
> optimisation is still pending investigations its getting delayed.
>
> Will find out if I can fix this panic in meantime with smaller change.
> Thanks for reminder.

Oh please sent bug fixes _before_ refactoring in that area. Otherwise
it's a pain for everybody backporting the fix to a stable kernel.

Thanks,
Johannes
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Johannes Thumshirn Storage
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