Re: [PATCH v3 0/9] Don't whitelist OA registers unconditionally

["Dixit, Ashutosh" <ashutosh.dixit@intel.com>]

On Mon, 22 Jun 2026 17:48:12 -0700, Dixit, Ashutosh wrote:
>
> On Mon, 15 Jun 2026 15:42:18 -0700, Ashutosh Dixit wrote:
> >
> > Whitelisting OA registers unconditionally is a security violation. In this
> > series we resolve this issue as follows:
> >
> > * Set the 'deny' bit (bit 30) for all OA registers, ensuring OA registers
> >   are not whitelisted by default after probe/reset/restart
> > * Reset the 'deny' bit when an OA stream is opened and certain conditions
> >   are met, whitelisting OA registers only for the duration when OA streams
> >   are open for a gt
> > * Set the 'deny' bit again, when OA streams are closed
> > * To manage this scheme, separate out OA whitelists from non-OA whitelists
> >   (into separate save-restore lists)
> >
> > v2: Address code review from Umesh. Patches changed in v2 have changelog
> >     appended to commit message
> > v3: Minor change to Patch 3
> >
> > Ashutosh Dixit (9):
> >   drm/xe/rtp: Add RING_FORCE_TO_NONPRIV_DENY to OA whitelists
> >   drm/xe/rtp: Maintain OA whitelists separately
> >   drm/xe/rtp: Keep track of non-OA nonpriv slots
> >   drm/xe/rtp: Generalize whitelist_apply_to_hwe
> >   drm/xe/rtp: Save OA nonpriv registers to register save/restore lists
> >   drm/xe/rtp: Toggle 'deny' bit to (de-)whitelist OA regs
> >   drm/xe/rtp: (De-)whitelist OA registers for all hwe's for a gt
> >   drm/xe/oa: (De-)whitelist OA registers on OA stream open/release
> >   drm/xe/rtp: Ensure locking/ref counting for OA whitelists
>
> I have added the following to all the patches here and merge this series:
>
>	Cc: stable@vger.kernel.org # v6.12+
>	Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>

Sorry I meant:

	Fixes: 828a8eaf37c3 ("drm/xe/oa: Add MMIO trigger support")
	Cc: stable@vger.kernel.org # v6.12+

>
> So the plan is to propagate this series to the previous LTS kernel versions
> too, in order to plug this security violation related to unconditional OA
> register whitelisting.
>
> I am preparing v6.12 and v6.18 stable kernel version series, based on this
> series. Since these are a bit old, this series needs porting to these old
> kernel versions. These will be sent after this series reaches Linus'
> master.

This is needed for patches to be added to stable versions.

>
> Thanks.
> --
> Ashutosh