6.1-stable review patch. If anyone has any objections, please let me know.
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From: Nitin Gote nitin.r.gote@intel.com
commit 65564157ae64cec0f527583f96e32f484f730f92 upstream.
We're seeing a GPU hang issue on a CHV platform, which was caused by commit bac24f59f454 ("drm/i915/execlists: Enable coarse preemption boundaries for Gen8").
The Gen8 platform only supports timeslicing and doesn't have a preemption mechanism, as its engines do not have a preemption timer.
Commit 751f82b353a6 ("drm/i915/gt: Only disable preemption on Gen8 render engines") addressed this issue only for render engines. This patch extends that fix by ensuring that preemption is not considered for all engines on Gen8 platforms.
v4: - Use the correct Fixes tag (Rodrigo Vivi) - Reworded commit log (Andi Shyti)
v3: - Inside need_preempt(), condition of can_preempt() is not required as simplified can_preempt() is enough. (Chris Wilson)
v2: Simplify can_preempt() function (Tvrtko Ursulin)
Fixes: 751f82b353a6 ("drm/i915/gt: Only disable preemption on gen8 render engines") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/11396 Suggested-by: Andi Shyti andi.shyti@intel.com Signed-off-by: Nitin Gote nitin.r.gote@intel.com Cc: Chris Wilson chris.p.wilson@linux.intel.com CC: stable@vger.kernel.org # v5.12+ Reviewed-by: Jonathan Cavitt jonathan.cavitt@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/20240711163208.1355736-1-nitin... (cherry picked from commit 7df0be6e6280c6fca01d039864bb123e5e36604b) Signed-off-by: Tvrtko Ursulin tursulin@ursulin.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/gt/intel_execlists_submission.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
--- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c @@ -3313,11 +3313,7 @@ static void remove_from_engine(struct i9
static bool can_preempt(struct intel_engine_cs *engine) { - if (GRAPHICS_VER(engine->i915) > 8) - return true; - - /* GPGPU on bdw requires extra w/a; not implemented */ - return engine->class != RENDER_CLASS; + return GRAPHICS_VER(engine->i915) > 8; }
static void kick_execlists(const struct i915_request *rq, int prio)