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FAILED: patch "[PATCH] drm/i915/execlists: Avoid reusing the same logical CCID" failed to apply to 5.6-stable tree

PATCH [email protected] 1 participant 1 message May 18, 2020

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Stable branch DRM drivers Intel i915 Intel GVT-g drivers (Intel GPU Virtualization)
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The patch below does not apply to the 5.6-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 53b2622e774681943230fb9f31096512fff99fe7 Mon Sep 17 00:00:00 2001
From: Chris Wilson <[email protected]>
Date: Tue, 28 Apr 2020 19:47:49 +0100
Subject: [PATCH] drm/i915/execlists: Avoid reusing the same logical CCID

The bspec is confusing on the nature of the upper 32bits of the LRC descriptor. Once upon a time, it said that it uses the upper 32b to decide if it should perform a lite-restore, and so we must ensure that each unique context submitted to HW is given a unique CCID [for the duration of it being on the HW]. Currently, this is achieved by using a small circular tag, and assigning every context submitted to HW a new id. However, this tag is being cleared on repinning an inflight context such that we end up re-using the 0 tag for multiple contexts.

To avoid accidentally clearing the CCID in the upper 32bits of the LRC descriptor, split the descriptor into two dwords so we can update the GGTT address separately from the CCID.

Closes https://gitlab.freedesktop.org/drm/intel/-/issues/1796
Fixes 2935ed5339c4 ("drm/i915: Remove logical HW ID")
Signed-off-by Chris Wilson <[email protected]>
Cc Mika Kuoppala <[email protected]>
Cc <[email protected]> # v5.5+
Reviewed-by Mika Kuoppala <[email protected]>
Link https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit 2632f174a2e1a5fd40a70404fa8ccfd0b1f79ebd)
(cherry picked from commit a4b70fcc587860f4b972f68217d8ebebe295ec15)
Signed-off-by Rodrigo Vivi <[email protected]>
drivers/gpu/drm/i915/gt/intel_context_types.h +7 -1
index 07cb83a0d017..ca0d4f4f3615 100644
@@ -69,7 +69,13 @@ struct intel_context {
 #define CONTEXT_NOPREEMPT		7
 
 	u32 *lrc_reg_state;
-	u64 lrc_desc;
+	union {
+		struct {
+			u32 lrca;
+			u32 ccid;
+		};
+		u64 desc;
+	} lrc;
 	u32 tag; /* cookie passed to HW to track this context on submission */
 
 	/* Time on GPU as tracked by the hw. */
drivers/gpu/drm/i915/gt/intel_engine_types.h +5 -0
index 763f8f530ded..8dd210a2c340 100644
@@ -156,6 +156,11 @@ struct intel_engine_execlists {
 	 */
 	struct i915_priolist default_priolist;
 
+	/**
+	 * @ccid: identifier for contexts submitted to this engine
+	 */
+	u32 ccid;
+
 	/**
 	 * @yield: CCID at the time of the last semaphore-wait interrupt.
 	 *
drivers/gpu/drm/i915/gt/intel_lrc.c +21 -29

125 lines not on this page · raw message

drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +1 -1
index fe7778c28d2d..aa6d56e25a10 100644
@@ -217,7 +217,7 @@ static void guc_wq_item_append(struct intel_guc *guc,
 static void guc_add_request(struct intel_guc *guc, struct i915_request *rq)
 {
 	struct intel_engine_cs *engine = rq->engine;
-	u32 ctx_desc = lower_32_bits(rq->context->lrc_desc);
+	u32 ctx_desc = rq->context->lrc.ccid;
 	u32 ring_tail = intel_ring_set_tail(rq->ring, rq->tail) / sizeof(u64);
 
 	guc_wq_item_append(guc, engine->guc_id, ctx_desc,
drivers/gpu/drm/i915/gvt/scheduler.c +2 -2
index cb11c3184085..6eb6710b35e9 100644
@@ -290,7 +290,7 @@ static void
 shadow_context_descriptor_update(struct intel_context *ce,
 				 struct intel_vgpu_workload *workload)
 {
-	u64 desc = ce->lrc_desc;
+	u64 desc = ce->lrc.desc;
 
 	/*
 	 * Update bits 0-11 of the context descriptor which includes flags

@@ -300,7 +300,7 @@ shadow_context_descriptor_update(struct intel_context *ce,
 	desc |= (u64)workload->ctx_desc.addressing_mode <<
 		GEN8_CTX_ADDRESSING_MODE_SHIFT;
 
-	ce->lrc_desc = desc;
+	ce->lrc.desc = desc;
 }
 
 static int copy_workload_to_ring_buffer(struct intel_vgpu_workload *workload)
drivers/gpu/drm/i915/i915_perf.c +1 -2
index 66a46e41d5ef..b5030192be3e 100644
@@ -1310,8 +1310,7 @@ static int oa_get_render_ctx_id(struct i915_perf_stream *stream)
 			 * dropped by GuC. They won't be part of the context
 			 * ID in the OA reports, so squash those lower bits.
 			 */
-			stream->specific_ctx_id =
-				lower_32_bits(ce->lrc_desc) >> 12;
+			stream->specific_ctx_id = ce->lrc.lrca >> 12;
 
 			/*
 			 * GuC uses the top bit to signal proxy submission, so