diff options
| author | Andrzej Hajda <andrzej.hajda@intel.com> | 2023-08-21 17:30:35 +0200 |
|---|---|---|
| committer | Rodrigo Vivi <rodrigo.vivi@intel.com> | 2023-08-30 11:32:48 -0400 |
| commit | 5eefc5307c983b59344a4cb89009819f580c84fa (patch) | |
| tree | 04a173a41f8db2f89166a7edd63187083149092c | |
| parent | 3698a75f5a98d0a6599e2878ab25d30a82dd836a (diff) | |
drm/i915: mark requests for GuC virtual engines to avoid use-after-free
References to i915_requests may be trapped by userspace inside a
sync_file or dmabuf (dma-resv) and held indefinitely across different
proceses. To counter-act the memory leaks, we try to not to keep
references from the request past their completion.
On the other side on fence release we need to know if rq->engine
is valid and points to hw engine (true for non-virtual requests).
To make it possible extra bit has been added to rq->execution_mask,
for marking virtual engines.
Fixes: bcb9aa45d5a0 ("Revert "drm/i915: Hold reference to intel_context over life of i915_request"")
Signed-off-by: Chris Wilson <chris.p.wilson@linux.intel.com>
Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230821153035.3903006-1-andrzej.hajda@intel.com
(cherry picked from commit 280410677af763f3871b93e794a199cfcf6fb580)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_engine_types.h | 1 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 3 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_request.c | 7 |
3 files changed, 6 insertions, 5 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_types.h b/drivers/gpu/drm/i915/gt/intel_engine_types.h index e99a6fa03d45..a7e677598004 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_types.h +++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h @@ -58,6 +58,7 @@ struct i915_perf_group; typedef u32 intel_engine_mask_t; #define ALL_ENGINES ((intel_engine_mask_t)~0ul) +#define VIRTUAL_ENGINES BIT(BITS_PER_TYPE(intel_engine_mask_t) - 1) struct intel_hw_status_page { struct list_head timelines; diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c index a0e3ef1c65d2..b5b7f2fe8c78 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -5470,6 +5470,9 @@ guc_create_virtual(struct intel_engine_cs **siblings, unsigned int count, ve->base.flags = I915_ENGINE_IS_VIRTUAL; + BUILD_BUG_ON(ilog2(VIRTUAL_ENGINES) < I915_NUM_ENGINES); + ve->base.mask = VIRTUAL_ENGINES; + intel_context_init(&ve->context, &ve->base); for (n = 0; n < count; n++) { diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index 7c7da284990d..f59081066a19 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -134,9 +134,7 @@ static void i915_fence_release(struct dma_fence *fence) i915_sw_fence_fini(&rq->semaphore); /* - * Keep one request on each engine for reserved use under mempressure - * do not use with virtual engines as this really is only needed for - * kernel contexts. + * Keep one request on each engine for reserved use under mempressure. * * We do not hold a reference to the engine here and so have to be * very careful in what rq->engine we poke. The virtual engine is @@ -166,8 +164,7 @@ static void i915_fence_release(struct dma_fence *fence) * know that if the rq->execution_mask is a single bit, rq->engine * can be a physical engine with the exact corresponding mask. */ - if (!intel_engine_is_virtual(rq->engine) && - is_power_of_2(rq->execution_mask) && + if (is_power_of_2(rq->execution_mask) && !cmpxchg(&rq->engine->request_pool, NULL, rq)) return; |