Re: [PATCH v3 0/8] kernel: taint when the driver firmware crashes

From: Luis Chamberlain
Date: Tue May 26 2020 - 19:07:53 EST

On Tue, May 26, 2020 at 03:46:06PM -0700, Jakub Kicinski wrote:
> On Tue, 26 May 2020 14:58:07 +0000 Luis Chamberlain wrote:
> > To those new on CC -- this is intended to be a simple generic interface
> > to the kernel to annotate when the firwmare has crashed leaving the
> > driver or system in a questionable state, in the worst case requiring
> > full system reboot. This series is first addressing only a few
> > networking patches, however, I already have an idea of where such
> > firmware crashes happen across the tree. The goal with this series then
> > is to first introduce the simple framework, and only if that moves
> > forward will I continue to chug on with the rest of the drivers /
> > subsystems.
> >
> > This is *not* a networking specific problem only.
> >
> > This v3 augments the last series by introducing the uevent for panic
> > events, one of them is during tainting. The uvent mechanism is
> > independent from any of this firmware taint mechanism. I've also
> > addressed Jessica Yu's feedback. Given I've extended the patches a bit
> > with other minor cleanup which complains over, and since
> > this infrastructure is still being discussed, I've trimmed the patch
> > series size to only cover drivers for which I've received an Acked-by
> > from the respective driver maintainer, or where we have bug reports to
> > support such dire situations on the driver such as ath10k.
> >
> > During the last v2 it was discussed that we should instead use devlink
> > for this work, however the initial RFC patches produced by Jakub
> > Kicinski [0] shows how devlink is networking specific, and the intent
> > behind this series is to produce simple helpers which can be used by *any*
> > device driver, for any subsystem, not just networking. Subsystem
> > specific infrastructure to help address firwmare crashes may still make
> > sense, however that does not mean we *don't* need something even more
> > generic regardless of the subsystem the issue happens on. Since uevents
> > for taints are exposed, we now expose these through uapi as well, and
> > that was something which eventually had to happen given that the current
> > scheme of relying on sensible character representations for each taint
> > will not scale beyond the alphabet.
> Nacked-by: Jakub Kicinski <kuba@xxxxxxxxxx>

Care to elaborate?