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Date:   Wed, 25 May 2022 09:10:16 +0300
From:   Leon Romanovsky <leon@kernel.org>
To:     Ryan Stone <rysto32@gmail.com>
Cc:     linux-rdma@vger.kernel.org
Subject: Re: Possible bug in ipoib_reap_dead_ahs in datagram mode
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On Tue, May 24, 2022 at 03:18:53PM -0400, Ryan Stone wrote:
> I believe that if we never enter that if statement, then we will leak
> the entries that are supposed to be cleaned up.  That's better than
> the use-after-free that I feared but still not good.

I don't know, we are running enhanced IPoIB all the time and I never got
any reports about kmemleaks/KASAN in that area.

Thanks

> 
> On Tue, May 24, 2022 at 3:08 PM Leon Romanovsky <leon@kernel.org> wrote:
> >
> > On Tue, May 24, 2022 at 09:33:52AM -0400, Ryan Stone wrote:
> > > On Tue, May 24, 2022 at 3:07 AM Leon Romanovsky <leon@kernel.org> wrote:
> > > > IPoIB in mlx5 is HW offloaded version of ulp/ipoib one. AFAIK, it doesn't
> > > > change "tx_tail" and we won't enter into this if (...).
> > > >
> > > > Thanks
> > >
> > > I don't quite follow this response.  Is this the if statement that you
> > > mean that we won't fall into?
> > >
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/infiniband/ulp/ipoib/ipoib_ib.c#n682
> >
> > Yes, I think so, maybe wrong here.