From 2471eb5fb6e1433e28426ece235e3730348019ec Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 23 Dec 2016 14:58:04 +0000 Subject: [PATCH] drm/i915: Prevent timeline updates whilst performing reset As the fence may be signaled concurrently from an interrupt on another device, it is possible for the list of requests on the timeline to be modified as we walk it. Take both (the context's timeline and the global timeline) locks to prevent such modifications. Fixes: 80b204bce8f2 ("drm/i915: Enable multiple timelines") Signed-off-by: Chris Wilson Cc: Joonas Lahtinen Cc: Mika Kuoppala Cc: Reviewed-by: Mika Kuoppala Link: http://patchwork.freedesktop.org/patch/msgid/20161223145804.6605-10-chris@chris-wilson.co.uk (cherry picked from commit 00c25e3f40083a6d5f1111955baccd287ee49258) Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/i915_gem.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 5d146f9f4aad..1e505d30b71e 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2730,6 +2730,7 @@ static void i915_gem_reset_engine(struct intel_engine_cs *engine) struct drm_i915_gem_request *request; struct i915_gem_context *incomplete_ctx; struct intel_timeline *timeline; + unsigned long flags; bool ring_hung; if (engine->irq_seqno_barrier) @@ -2765,13 +2766,20 @@ static void i915_gem_reset_engine(struct intel_engine_cs *engine) if (i915_gem_context_is_default(incomplete_ctx)) return; + timeline = i915_gem_context_lookup_timeline(incomplete_ctx, engine); + + spin_lock_irqsave(&engine->timeline->lock, flags); + spin_lock(&timeline->lock); + list_for_each_entry_continue(request, &engine->timeline->requests, link) if (request->ctx == incomplete_ctx) reset_request(request); - timeline = i915_gem_context_lookup_timeline(incomplete_ctx, engine); list_for_each_entry(request, &timeline->requests, link) reset_request(request); + + spin_unlock(&timeline->lock); + spin_unlock_irqrestore(&engine->timeline->lock, flags); } void i915_gem_reset(struct drm_i915_private *dev_priv) -- 2.45.2