On Mon, Apr 25, 2022 at 04:57:26PM -0700, Luis Chamberlain wrote: > On Mon, Apr 25, 2022 at 04:34:34PM -0700, Andrew Morton wrote: > > On Mon, 25 Apr 2022 16:08:57 -0700 Luis Chamberlain <mcgrof@xxxxxxxxxx> wrote: > > > > > On Mon, Apr 25, 2022 at 02:46:07PM -0700, Andrew Morton wrote: > > > > On Mon, 25 Apr 2022 12:00:21 -0700 Luis Chamberlain <mcgrof@xxxxxxxxxx> wrote: > > > > > > > > > Andrew, can we drop this patch for now? > > > > > > > > I've been sitting on (ie, forgotten about) this patch > > > > (https://lore.kernel.org/all/20200709235115.56954-1-jpitti@xxxxxxxxx/T/#u) > > > > > > Jesh, yeah I see. > > > > > > > for two years. Evidently waiting for you/Kees/Ingo to provide > > > > guidance. So sure, the need seems very unurgent so I can drop it. > > > > > > Well Keew as OK with it, but I yeah I can't decipher the issue at this > > > point in time. > > > > > > > However I fail to see how that patch could have caused this crash. I'm > > > > suspecting a bisection error? > > > > > > > > Maybe something is unwell in drivers/vdpa/vdpa_user/vduse_dev.c. > > > > > > At a quick glance, yes it could very well by vduse_init() is messy and > > > races somehow with init, but if a race does lurk here my instincts tell > > > me this can't be the only place. > > > > > > Not sure if leaving a patch in place more time to see how else things > > > can explode is worth it. > > > > Confused. Are you thinking that the above-linked patch was somehow > > involved in this crash? If so, but how? All it does it to permit > > unprivileged reads to four ints via proc_dointvec_minmax()? > > If the priv allows for it access to dereferencing a pointer is allowed. > How that race happens though, indeed is beyond the patch's fault. Even so, I am 99.99% sure this is a driver bug then. And so if enabling this patch just enables more driver bugs so be it. So driver maintainers: please take a look, I tried to check but the driver bug is not obvious to me yet. Luis _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
