If we have a set of active engines marked as being non-persistent, we
lose track of those if the user replaces those engines with
I915_CONTEXT_PARAM_ENGINES. As part of our uABI contract is that
non-persistent requests are terminated if they are no longer being
tracked by the user's context (in order to prevent a lost request
causing an untracked and so unstoppable GPU hang), we need to apply the
same context cancellation upon changing engines.

Fixes: a0e047156cde ("drm/i915/gem: Make context persistence optional")
Testcase: XXX
Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursu...@intel.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_context.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c 
b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 52a749691a8d..20f1d3e0221f 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -1624,11 +1624,18 @@ set_engines(struct i915_gem_context *ctx,
 
 replace:
        mutex_lock(&ctx->engines_mutex);
+
+       /* Flush stale requests off the old engines if required */
+       if (!i915_gem_context_is_persistent(ctx) ||
+           !i915_modparams.enable_hangcheck)
+               kill_context(ctx);
+
        if (args->size)
                i915_gem_context_set_user_engines(ctx);
        else
                i915_gem_context_clear_user_engines(ctx);
        set.engines = rcu_replace_pointer(ctx->engines, set.engines, 1);
+
        mutex_unlock(&ctx->engines_mutex);
 
        call_rcu(&set.engines->rcu, free_engines_rcu);
-- 
2.25.0

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to