On Thu, Jul 15, 2021 at 09:10:28PM -0700, Daniele Ceraolo Spurio wrote: > From: "Huang, Sean Z" <sean.z.huang@xxxxxxxxx> > > The HW will generate a teardown interrupt when session termination is > required, which requires i915 to submit a terminating batch. Once the HW > is done with the termination it will generate another interrupt, at > which point it is safe to re-create the session. > > Since the termination and re-creation flow is something we want to > trigger from the driver as well, use a common work function that can be > called both from the irq handler and from the driver set-up flows, which > has the addded benefit of allowing us to skip any extra locks because > the work itself serializes the operations. > > v2: use struct completion instead of bool (Chris) > v3: drop locks, clean up functions and improve comments (Chris), > move to common work function. > v4: improve comments, simplify wait logic (Rodrigo) > v5: unconditionally set interrupts, I didn't find this... this looks the same as v4 > rename state_attacked var (Rodrigo) thanks > > Signed-off-by: Huang, Sean Z <sean.z.huang@xxxxxxxxx> > Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx> > Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> #v4 anyway, this patch looks good to me... Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > --- > drivers/gpu/drm/i915/Makefile | 1 + > drivers/gpu/drm/i915/gt/intel_gt_irq.c | 7 ++ > drivers/gpu/drm/i915/i915_reg.h | 1 + > drivers/gpu/drm/i915/pxp/intel_pxp.c | 66 +++++++++++-- > drivers/gpu/drm/i915/pxp/intel_pxp.h | 8 ++ > drivers/gpu/drm/i915/pxp/intel_pxp_irq.c | 99 ++++++++++++++++++++ > drivers/gpu/drm/i915/pxp/intel_pxp_irq.h | 32 +++++++ > drivers/gpu/drm/i915/pxp/intel_pxp_session.c | 54 ++++++++++- > drivers/gpu/drm/i915/pxp/intel_pxp_session.h | 5 +- > drivers/gpu/drm/i915/pxp/intel_pxp_tee.c | 8 +- > drivers/gpu/drm/i915/pxp/intel_pxp_types.h | 18 ++++ > 11 files changed, 283 insertions(+), 16 deletions(-) > create mode 100644 drivers/gpu/drm/i915/pxp/intel_pxp_irq.c > create mode 100644 drivers/gpu/drm/i915/pxp/intel_pxp_irq.h > > diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile > index 44d3a2bcb64c..1714089a10f0 100644 > --- a/drivers/gpu/drm/i915/Makefile > +++ b/drivers/gpu/drm/i915/Makefile > @@ -279,6 +279,7 @@ i915-y += i915_perf.o > i915-$(CONFIG_DRM_I915_PXP) += \ > pxp/intel_pxp.o \ > pxp/intel_pxp_cmd.o \ > + pxp/intel_pxp_irq.o \ > pxp/intel_pxp_session.o \ > pxp/intel_pxp_tee.o > > diff --git a/drivers/gpu/drm/i915/gt/intel_gt_irq.c b/drivers/gpu/drm/i915/gt/intel_gt_irq.c > index c13462274fe8..96f0e9172a09 100644 > --- a/drivers/gpu/drm/i915/gt/intel_gt_irq.c > +++ b/drivers/gpu/drm/i915/gt/intel_gt_irq.c > @@ -13,6 +13,7 @@ > #include "intel_lrc_reg.h" > #include "intel_uncore.h" > #include "intel_rps.h" > +#include "pxp/intel_pxp_irq.h" > > static void guc_irq_handler(struct intel_guc *guc, u16 iir) > { > @@ -64,6 +65,9 @@ gen11_other_irq_handler(struct intel_gt *gt, const u8 instance, > if (instance == OTHER_GTPM_INSTANCE) > return gen11_rps_irq_handler(>->rps, iir); > > + if (instance == OTHER_KCR_INSTANCE) > + return intel_pxp_irq_handler(>->pxp, iir); > + > WARN_ONCE(1, "unhandled other interrupt instance=0x%x, iir=0x%x\n", > instance, iir); > } > @@ -190,6 +194,9 @@ void gen11_gt_irq_reset(struct intel_gt *gt) > intel_uncore_write(uncore, GEN11_GPM_WGBOXPERF_INTR_MASK, ~0); > intel_uncore_write(uncore, GEN11_GUC_SG_INTR_ENABLE, 0); > intel_uncore_write(uncore, GEN11_GUC_SG_INTR_MASK, ~0); > + > + intel_uncore_write(uncore, GEN11_CRYPTO_RSVD_INTR_ENABLE, 0); > + intel_uncore_write(uncore, GEN11_CRYPTO_RSVD_INTR_MASK, ~0); > } > > void gen11_gt_irq_postinstall(struct intel_gt *gt) > diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h > index 943fe485c662..2c583f2d410d 100644 > --- a/drivers/gpu/drm/i915/i915_reg.h > +++ b/drivers/gpu/drm/i915/i915_reg.h > @@ -8051,6 +8051,7 @@ enum { > /* irq instances for OTHER_CLASS */ > #define OTHER_GUC_INSTANCE 0 > #define OTHER_GTPM_INSTANCE 1 > +#define OTHER_KCR_INSTANCE 4 > > #define GEN11_INTR_IDENTITY_REG(x) _MMIO(0x190060 + ((x) * 4)) > > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c b/drivers/gpu/drm/i915/pxp/intel_pxp.c > index 26176d43a02d..b0c7edc10cc3 100644 > --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c > @@ -2,7 +2,9 @@ > /* > * Copyright(c) 2020 Intel Corporation. > */ > +#include <linux/workqueue.h> > #include "intel_pxp.h" > +#include "intel_pxp_irq.h" > #include "intel_pxp_session.h" > #include "intel_pxp_tee.h" > #include "gt/intel_context.h" > @@ -68,6 +70,16 @@ void intel_pxp_init(struct intel_pxp *pxp) > > mutex_init(&pxp->tee_mutex); > > + /* > + * we'll use the completion to check if there is a termination pending, > + * so we start it as completed and we reinit it when a termination > + * is triggered. > + */ > + init_completion(&pxp->termination); > + complete_all(&pxp->termination); > + > + INIT_WORK(&pxp->session_work, intel_pxp_session_work); > + > ret = create_vcs_context(pxp); > if (ret) > return; > @@ -96,19 +108,61 @@ void intel_pxp_fini(struct intel_pxp *pxp) > destroy_vcs_context(pxp); > } > > -void intel_pxp_init_hw(struct intel_pxp *pxp) > +void intel_pxp_mark_termination_in_progress(struct intel_pxp *pxp) > { > - int ret; > + pxp->arb_is_valid = false; > + reinit_completion(&pxp->termination); > +} > + > +static void intel_pxp_queue_termination(struct intel_pxp *pxp) > +{ > + struct intel_gt *gt = pxp_to_gt(pxp); > + > + /* > + * We want to get the same effect as if we received a termination > + * interrupt, so just pretend that we did. > + */ > + spin_lock_irq(>->irq_lock); > + intel_pxp_mark_termination_in_progress(pxp); > + pxp->session_events |= PXP_TERMINATION_REQUEST; > + queue_work(system_unbound_wq, &pxp->session_work); > + spin_unlock_irq(>->irq_lock); > +} > > +/* > + * the arb session is restarted from the irq work when we receive the > + * termination completion interrupt > + */ > +int intel_pxp_wait_for_arb_start(struct intel_pxp *pxp) > +{ > + if (!intel_pxp_is_enabled(pxp)) > + return 0; > + > + if (!wait_for_completion_timeout(&pxp->termination, > + msecs_to_jiffies(100))) > + return -ETIMEDOUT; > + > + if (!pxp->arb_is_valid) > + return -EIO; > + > + return 0; > +} > + > +void intel_pxp_init_hw(struct intel_pxp *pxp) > +{ > kcr_pxp_enable(pxp_to_gt(pxp)); > + intel_pxp_irq_enable(pxp); > > - /* always emit a full termination to clean the state */ > - ret = intel_pxp_terminate_arb_session_and_global(pxp); > - if (!ret) > - intel_pxp_create_arb_session(pxp); > + /* > + * the session could've been attacked while we weren't loaded, so > + * handle it as if it was and re-create it. > + */ > + intel_pxp_queue_termination(pxp); > } > > void intel_pxp_fini_hw(struct intel_pxp *pxp) > { > kcr_pxp_disable(pxp_to_gt(pxp)); > + > + intel_pxp_irq_disable(pxp); > } > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.h b/drivers/gpu/drm/i915/pxp/intel_pxp.h > index 8eeb65af78b1..074b3b980957 100644 > --- a/drivers/gpu/drm/i915/pxp/intel_pxp.h > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.h > @@ -30,6 +30,9 @@ void intel_pxp_fini(struct intel_pxp *pxp); > > void intel_pxp_init_hw(struct intel_pxp *pxp); > void intel_pxp_fini_hw(struct intel_pxp *pxp); > + > +void intel_pxp_mark_termination_in_progress(struct intel_pxp *pxp); > +int intel_pxp_wait_for_arb_start(struct intel_pxp *pxp); > #else > static inline void intel_pxp_init(struct intel_pxp *pxp) > { > @@ -38,6 +41,11 @@ static inline void intel_pxp_init(struct intel_pxp *pxp) > static inline void intel_pxp_fini(struct intel_pxp *pxp) > { > } > + > +static inline int intel_pxp_wait_for_arb_start(struct intel_pxp *pxp) > +{ > + return 0; > +} > #endif > > #endif /* __INTEL_PXP_H__ */ > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_irq.c b/drivers/gpu/drm/i915/pxp/intel_pxp_irq.c > new file mode 100644 > index 000000000000..46eca1e81b9b > --- /dev/null > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_irq.c > @@ -0,0 +1,99 @@ > +// SPDX-License-Identifier: MIT > +/* > + * Copyright(c) 2020 Intel Corporation. > + */ > +#include <linux/workqueue.h> > +#include "intel_pxp.h" > +#include "intel_pxp_irq.h" > +#include "intel_pxp_session.h" > +#include "gt/intel_gt_irq.h" > +#include "i915_irq.h" > +#include "i915_reg.h" > + > +/** > + * intel_pxp_irq_handler - Handles PXP interrupts. > + * @pxp: pointer to pxp struct > + * @iir: interrupt vector > + */ > +void intel_pxp_irq_handler(struct intel_pxp *pxp, u16 iir) > +{ > + struct intel_gt *gt = pxp_to_gt(pxp); > + > + if (GEM_WARN_ON(!intel_pxp_is_enabled(pxp))) > + return; > + > + lockdep_assert_held(>->irq_lock); > + > + if (unlikely(!iir)) > + return; > + > + if (iir & (GEN12_DISPLAY_PXP_STATE_TERMINATED_INTERRUPT | > + GEN12_DISPLAY_APP_TERMINATED_PER_FW_REQ_INTERRUPT)) { > + /* immediately mark PXP as inactive on termination */ > + intel_pxp_mark_termination_in_progress(pxp); > + pxp->session_events |= PXP_TERMINATION_REQUEST; > + } > + > + if (iir & GEN12_DISPLAY_STATE_RESET_COMPLETE_INTERRUPT) > + pxp->session_events |= PXP_TERMINATION_COMPLETE; > + > + if (pxp->session_events) > + queue_work(system_unbound_wq, &pxp->session_work); > +} > + > +static inline void __pxp_set_interrupts(struct intel_gt *gt, u32 interrupts) > +{ > + struct intel_uncore *uncore = gt->uncore; > + const u32 mask = interrupts << 16; > + > + intel_uncore_write(uncore, GEN11_CRYPTO_RSVD_INTR_ENABLE, mask); > + intel_uncore_write(uncore, GEN11_CRYPTO_RSVD_INTR_MASK, ~mask); > +} > + > +static inline void pxp_irq_reset(struct intel_gt *gt) > +{ > + spin_lock_irq(>->irq_lock); > + gen11_gt_reset_one_iir(gt, 0, GEN11_KCR); > + spin_unlock_irq(>->irq_lock); > +} > + > +void intel_pxp_irq_enable(struct intel_pxp *pxp) > +{ > + struct intel_gt *gt = pxp_to_gt(pxp); > + > + spin_lock_irq(>->irq_lock); > + > + if (!pxp->irq_enabled) > + WARN_ON_ONCE(gen11_gt_reset_one_iir(gt, 0, GEN11_KCR)); > + > + __pxp_set_interrupts(gt, GEN12_PXP_INTERRUPTS); > + pxp->irq_enabled = true; > + > + spin_unlock_irq(>->irq_lock); > +} > + > +void intel_pxp_irq_disable(struct intel_pxp *pxp) > +{ > + struct intel_gt *gt = pxp_to_gt(pxp); > + > + /* > + * We always need to submit a global termination when we re-enable the > + * interrupts, so there is no need to make sure that the session state > + * makes sense at the end of this function. Just make sure this is not > + * called in a path were the driver consider the session as valid and > + * doesn't call a termination on restart. > + */ > + GEM_WARN_ON(intel_pxp_is_active(pxp)); > + > + spin_lock_irq(>->irq_lock); > + > + pxp->irq_enabled = false; > + __pxp_set_interrupts(gt, 0); > + > + spin_unlock_irq(>->irq_lock); > + intel_synchronize_irq(gt->i915); > + > + pxp_irq_reset(gt); > + > + flush_work(&pxp->session_work); > +} > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_irq.h b/drivers/gpu/drm/i915/pxp/intel_pxp_irq.h > new file mode 100644 > index 000000000000..8b5793654844 > --- /dev/null > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_irq.h > @@ -0,0 +1,32 @@ > +/* SPDX-License-Identifier: MIT */ > +/* > + * Copyright(c) 2020, Intel Corporation. All rights reserved. > + */ > + > +#ifndef __INTEL_PXP_IRQ_H__ > +#define __INTEL_PXP_IRQ_H__ > + > +#include <linux/types.h> > + > +struct intel_pxp; > + > +#define GEN12_DISPLAY_PXP_STATE_TERMINATED_INTERRUPT BIT(1) > +#define GEN12_DISPLAY_APP_TERMINATED_PER_FW_REQ_INTERRUPT BIT(2) > +#define GEN12_DISPLAY_STATE_RESET_COMPLETE_INTERRUPT BIT(3) > + > +#define GEN12_PXP_INTERRUPTS \ > + (GEN12_DISPLAY_PXP_STATE_TERMINATED_INTERRUPT | \ > + GEN12_DISPLAY_APP_TERMINATED_PER_FW_REQ_INTERRUPT | \ > + GEN12_DISPLAY_STATE_RESET_COMPLETE_INTERRUPT) > + > +#ifdef CONFIG_DRM_I915_PXP > +void intel_pxp_irq_enable(struct intel_pxp *pxp); > +void intel_pxp_irq_disable(struct intel_pxp *pxp); > +void intel_pxp_irq_handler(struct intel_pxp *pxp, u16 iir); > +#else > +static inline void intel_pxp_irq_handler(struct intel_pxp *pxp, u16 iir) > +{ > +} > +#endif > + > +#endif /* __INTEL_PXP_IRQ_H__ */ > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c > index b8e24adeb1f3..67c30e534d50 100644 > --- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c > @@ -48,7 +48,7 @@ static int pxp_wait_for_session_state(struct intel_pxp *pxp, u32 id, bool in_pla > return ret; > } > > -int intel_pxp_create_arb_session(struct intel_pxp *pxp) > +static int pxp_create_arb_session(struct intel_pxp *pxp) > { > struct intel_gt *gt = pxp_to_gt(pxp); > int ret; > @@ -77,12 +77,13 @@ int intel_pxp_create_arb_session(struct intel_pxp *pxp) > return 0; > } > > -int intel_pxp_terminate_arb_session_and_global(struct intel_pxp *pxp) > +static int pxp_terminate_arb_session_and_global(struct intel_pxp *pxp) > { > int ret; > struct intel_gt *gt = pxp_to_gt(pxp); > > - pxp->arb_is_valid = false; > + /* must mark termination in progress calling this function */ > + GEM_WARN_ON(pxp->arb_is_valid); > > /* terminate the hw sessions */ > ret = intel_pxp_terminate_session(pxp, ARB_SESSION); > @@ -101,3 +102,50 @@ int intel_pxp_terminate_arb_session_and_global(struct intel_pxp *pxp) > > return ret; > } > + > +static void pxp_terminate(struct intel_pxp *pxp) > +{ > + int ret; > + > + pxp->hw_state_invalidated = true; > + > + /* > + * if we fail to submit the termination there is no point in waiting for > + * it to complete. PXP will be marked as non-active until the next > + * termination is issued. > + */ > + ret = pxp_terminate_arb_session_and_global(pxp); > + if (ret) > + complete_all(&pxp->termination); > +} > + > +static void pxp_terminate_complete(struct intel_pxp *pxp) > +{ > + /* Re-create the arb session after teardown handle complete */ > + if (fetch_and_zero(&pxp->hw_state_invalidated)) > + pxp_create_arb_session(pxp); > + > + complete_all(&pxp->termination); > +} > + > +void intel_pxp_session_work(struct work_struct *work) > +{ > + struct intel_pxp *pxp = container_of(work, typeof(*pxp), session_work); > + struct intel_gt *gt = pxp_to_gt(pxp); > + u32 events = 0; > + > + spin_lock_irq(>->irq_lock); > + events = fetch_and_zero(&pxp->session_events); > + spin_unlock_irq(>->irq_lock); > + > + if (!events) > + return; > + > + if (events & PXP_TERMINATION_REQUEST) { > + events &= ~PXP_TERMINATION_COMPLETE; > + pxp_terminate(pxp); > + } > + > + if (events & PXP_TERMINATION_COMPLETE) > + pxp_terminate_complete(pxp); > +} > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.h b/drivers/gpu/drm/i915/pxp/intel_pxp_session.h > index 7354314b1cc4..ba4c9d2b94b7 100644 > --- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.h > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.h > @@ -8,9 +8,8 @@ > > #include <linux/types.h> > > -struct intel_pxp; > +struct work_struct; > > -int intel_pxp_create_arb_session(struct intel_pxp *pxp); > -int intel_pxp_terminate_arb_session_and_global(struct intel_pxp *pxp); > +void intel_pxp_session_work(struct work_struct *work); > > #endif /* __INTEL_PXP_SESSION_H__ */ > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c > index 3662bf67407a..7693540dc1f9 100644 > --- a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c > @@ -80,6 +80,7 @@ static int i915_pxp_tee_component_bind(struct device *i915_kdev, > { > struct drm_i915_private *i915 = kdev_to_i915(i915_kdev); > struct intel_pxp *pxp = i915_dev_to_pxp(i915_kdev); > + int ret; > > mutex_lock(&pxp->tee_mutex); > pxp->pxp_component = data; > @@ -88,15 +89,14 @@ static int i915_pxp_tee_component_bind(struct device *i915_kdev, > > /* the component is required to fully start the PXP HW */ > intel_pxp_init_hw(pxp); > - > - if (!pxp->arb_is_valid) { > + ret = intel_pxp_wait_for_arb_start(pxp); > + if (ret) { > drm_err(&i915->drm, "Failed to create arb session during bind\n"); > intel_pxp_fini_hw(pxp); > pxp->pxp_component = NULL; > - return -EIO; > } > > - return 0; > + return ret; > } > > static void i915_pxp_tee_component_unbind(struct device *i915_kdev, > diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h > index a4797a98c1f9..475e3312c287 100644 > --- a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h > +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h > @@ -6,8 +6,10 @@ > #ifndef __INTEL_PXP_TYPES_H__ > #define __INTEL_PXP_TYPES_H__ > > +#include <linux/completion.h> > #include <linux/mutex.h> > #include <linux/types.h> > +#include <linux/workqueue.h> > > struct intel_context; > struct i915_pxp_component; > @@ -25,6 +27,22 @@ struct intel_pxp { > bool arb_is_valid; > > struct mutex tee_mutex; /* protects the tee channel binding */ > + > + /* > + * If the HW perceives an attack on the integrity of the encryption it > + * will invalidate the keys and expect SW to re-initialize the session. > + * We keep track of this state to make sure we only re-start the arb > + * session when required. > + */ > + bool hw_state_invalidated; > + > + bool irq_enabled; > + struct completion termination; > + > + struct work_struct session_work; > + u32 session_events; /* protected with gt->irq_lock */ > +#define PXP_TERMINATION_REQUEST BIT(0) > +#define PXP_TERMINATION_COMPLETE BIT(1) > }; > > #endif /* __INTEL_PXP_TYPES_H__ */ > -- > 2.32.0 >