On Tue, 2023-01-24 at 10:17 -0500, Rodrigo Vivi wrote:
> On Mon, Jan 23, 2023 at 09:31:49PM -0800, Alan Previn wrote:
> > A driver bug was recently discovered where the security firmware
> > was
> > receiving internal HW signals indicating that session key
> > expirations
> > had occurred. Architecturally, the firmware was expecting a
> > response
> > from the GuC to acknowledge the event with the firmware side.
> > However the OS was in a suspended state and GuC had been reset.
> >
> > Internal specifications actually required the driver to ensure
> > that all active sessions be properly cleaned up in such cases where
> > the system is suspended and the GuC potentially unable to respond.
> >
> > This patch adds the global teardown code in i915's suspend_prepare
> > code path.
> >
> > Signed-off-by: Alan Previn <alan.previn.teres.alexis@xxxxxxxxx>
> > Reviewed-by: Juston Li <justonli@xxxxxxxxxxxx>
>
> it should probably contain some revision history above so the
> reviewer can know what changed from the time he reviewed and now.
>
> it looks we have another function that I don't remember...
> Juston, could you please confirm your review stands in this version?
> if so feel free to add my ack with that.
Sure, v6 is:
Reviewed-by: Juston Li <justonli@xxxxxxxxxxxx>
Appreciate the reviews/revisions Rodrigo and Alan!
>
> > ---
> > drivers/gpu/drm/i915/pxp/intel_pxp.c | 65
> > +++++++++++++++++---
> > drivers/gpu/drm/i915/pxp/intel_pxp.h | 1 +
> > drivers/gpu/drm/i915/pxp/intel_pxp_pm.c | 2 +-
> > drivers/gpu/drm/i915/pxp/intel_pxp_session.c | 6 +-
> > drivers/gpu/drm/i915/pxp/intel_pxp_session.h | 5 ++
> > 5 files changed, 66 insertions(+), 13 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> > b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> > index cfc9af8b3d21..9d4c7724e98e 100644
> > --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> > @@ -270,6 +270,60 @@ static bool pxp_component_bound(struct
> > intel_pxp *pxp)
> > return bound;
> > }
> >
> > +static int __pxp_global_teardown_final(struct intel_pxp *pxp)
> > +{
> > + if (!pxp->arb_is_valid)
> > + return 0;
> > + /*
> > + * To ensure synchronous and coherent session teardown
> > completion
> > + * in response to suspend or shutdown triggers, don't use a
> > worker.
> > + */
> > + intel_pxp_mark_termination_in_progress(pxp);
> > + intel_pxp_terminate(pxp, false);
> > +
> > + if (!wait_for_completion_timeout(&pxp->termination,
> > msecs_to_jiffies(250)))
> > + return -ETIMEDOUT;
> > +
> > + return 0;
> > +}
> > +
> > +static int __pxp_global_teardown_restart(struct intel_pxp *pxp)
> > +{
> > + if (pxp->arb_is_valid)
> > + return 0;
> > + /*
> > + * The arb-session is currently inactive and we are doing a
> > reset and restart
> > + * due to a runtime event. Use the worker that was designed
> > for this.
> > + */
> > + pxp_queue_termination(pxp);
> > +
> > + if (!wait_for_completion_timeout(&pxp->termination,
> > msecs_to_jiffies(250)))
> > + return -ETIMEDOUT;
> > +
> > + return 0;
> > +}
> > +
> > +void intel_pxp_end(struct intel_pxp *pxp)
> > +{
> > + struct drm_i915_private *i915 = pxp->ctrl_gt->i915;
> > + intel_wakeref_t wakeref;
> > +
> > + if (!intel_pxp_is_enabled(pxp))
> > + return;
> > +
> > + wakeref = intel_runtime_pm_get(&i915->runtime_pm);
> > +
> > + mutex_lock(&pxp->arb_mutex);
> > +
> > + if (__pxp_global_teardown_final(pxp))
> > + drm_dbg(&i915->drm, "PXP end timed out\n");
> > +
> > + mutex_unlock(&pxp->arb_mutex);
> > +
> > + intel_pxp_fini_hw(pxp);
> > + intel_runtime_pm_put(&i915->runtime_pm, wakeref);
> > +}
> > +
> > /*
> > * the arb session is restarted from the irq work when we receive
> > the
> > * termination completion interrupt
> > @@ -286,16 +340,9 @@ int intel_pxp_start(struct intel_pxp *pxp)
> >
> > mutex_lock(&pxp->arb_mutex);
> >
> > - if (pxp->arb_is_valid)
> > - goto unlock;
> > -
> > - pxp_queue_termination(pxp);
> > -
> > - if (!wait_for_completion_timeout(&pxp->termination,
> > - msecs_to_jiffies(250))) {
> > - ret = -ETIMEDOUT;
> > + ret = __pxp_global_teardown_restart(pxp);
> > + if (ret)
> > goto unlock;
> > - }
> >
> > /* make sure the compiler doesn't optimize the double
> > access */
> > barrier();
> > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.h
> > b/drivers/gpu/drm/i915/pxp/intel_pxp.h
> > index 9658d3005222..3ded0890cd27 100644
> > --- a/drivers/gpu/drm/i915/pxp/intel_pxp.h
> > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.h
> > @@ -27,6 +27,7 @@ void
> > intel_pxp_mark_termination_in_progress(struct intel_pxp *pxp);
> > void intel_pxp_tee_end_arb_fw_session(struct intel_pxp *pxp, u32
> > arb_session_id);
> >
> > int intel_pxp_start(struct intel_pxp *pxp);
> > +void intel_pxp_end(struct intel_pxp *pxp);
> >
> > int intel_pxp_key_check(struct intel_pxp *pxp,
> > struct drm_i915_gem_object *obj,
> > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> > b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> > index 892d39cc61c1..e427464aa131 100644
> > --- a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> > @@ -16,7 +16,7 @@ void intel_pxp_suspend_prepare(struct intel_pxp
> > *pxp)
> > if (!intel_pxp_is_enabled(pxp))
> > return;
> >
> > - pxp->arb_is_valid = false;
> > + intel_pxp_end(pxp);
> >
> > intel_pxp_invalidate(pxp);
> > }
> > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> > b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> > index 74ed7e16e481..448cacb0465d 100644
> > --- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> > @@ -115,11 +115,11 @@ static int
> > pxp_terminate_arb_session_and_global(struct intel_pxp *pxp)
> > return ret;
> > }
> >
> > -static void pxp_terminate(struct intel_pxp *pxp)
> > +void intel_pxp_terminate(struct intel_pxp *pxp, bool
> > post_invalidation_needs_restart)
> > {
> > int ret;
> >
> > - pxp->hw_state_invalidated = true;
> > + pxp->hw_state_invalidated =
> > post_invalidation_needs_restart;
> >
> > /*
> > * if we fail to submit the termination there is no point
> > in waiting for
> > @@ -167,7 +167,7 @@ static void pxp_session_work(struct work_struct
> > *work)
> >
> > if (events & PXP_TERMINATION_REQUEST) {
> > events &= ~PXP_TERMINATION_COMPLETE;
> > - pxp_terminate(pxp);
> > + intel_pxp_terminate(pxp, true);
> > }
> >
> > if (events & PXP_TERMINATION_COMPLETE)
> > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.h
> > b/drivers/gpu/drm/i915/pxp/intel_pxp_session.h
> > index 903ac52cffa1..ba5788127109 100644
> > --- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.h
> > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.h
> > @@ -12,9 +12,14 @@ struct intel_pxp;
> >
> > #ifdef CONFIG_DRM_I915_PXP
> > void intel_pxp_session_management_init(struct intel_pxp *pxp);
> > +void intel_pxp_terminate(struct intel_pxp *pxp, bool
> > post_invalidation_needs_restart);
> > #else
> > static inline void intel_pxp_session_management_init(struct
> > intel_pxp *pxp)
> > {
> > }
> > +
> > +static inline void intel_pxp_terminate(struct intel_pxp *pxp, bool
> > post_invalidation_needs_restart)
> > +{
> > +}
> > #endif
> > #endif /* __INTEL_PXP_SESSION_H__ */
> > --
> > 2.39.0
> >
