From: Mauro Carvalho Chehab mchehab+samsung@kernel.org
i915 selftest hangcheck is causing the i915 driver timeouts, as reported by Intel CI:
http://gfx-ci.fi.intel.com/cibuglog-ng/issuefilterassoc/24297?query_key=42a9...
When such test runs, the only output is:
[ 68.811639] i915: Performing live selftests with st_random_seed=0xe138eac7 st_timeout=500 [ 68.811792] i915: Running hangcheck [ 68.811859] i915: Running intel_hangcheck_live_selftests/igt_hang_sanitycheck [ 68.816910] i915 0000:00:02.0: [drm] Cannot find any crtc or sizes [ 68.841597] i915: Running intel_hangcheck_live_selftests/igt_reset_nop [ 69.346347] igt_reset_nop: 80 resets [ 69.362695] i915: Running intel_hangcheck_live_selftests/igt_reset_nop_engine [ 69.863559] igt_reset_nop_engine(rcs0): 709 resets [ 70.364924] igt_reset_nop_engine(bcs0): 903 resets [ 70.866005] igt_reset_nop_engine(vcs0): 659 resets [ 71.367934] igt_reset_nop_engine(vcs1): 549 resets [ 71.869259] igt_reset_nop_engine(vecs0): 553 resets [ 71.882592] i915: Running intel_hangcheck_live_selftests/igt_reset_idle_engine [ 72.383554] rcs0: Completed 16605 idle resets [ 72.884599] bcs0: Completed 18641 idle resets [ 73.385592] vcs0: Completed 17517 idle resets [ 73.886658] vcs1: Completed 15474 idle resets [ 74.387600] vecs0: Completed 17983 idle resets [ 74.387667] i915: Running intel_hangcheck_live_selftests/igt_reset_active_engine [ 74.889017] rcs0: Completed 747 active resets [ 75.174240] intel_engine_reset(bcs0) failed, err:-110 [ 75.174301] bcs0: Completed 525 active resets
After that, the machine just silently hangs.
The root cause is that the flush TLB logic is not working as expected on GEN8.
Tested on an Intel NUC5i7RYB with an i7-5557U Broadwell CPU.
This patch partially reverts the logic by skipping GEN8 from the TLB cache flush.
Cc: Tvrtko Ursulin tvrtko.ursulin@intel.com Cc: Sushma Venkatesh Reddy sushma.venkatesh.reddy@intel.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Dave Airlie airlied@redhat.com Cc: Jon Bloomfield jon.bloomfield@intel.com Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: Jani Nikula jani.nikula@intel.com Cc: stable@vger.kernel.org # Kernel 5.17 and upper
Fixes: 494c2c9b630e ("drm/i915: Flush TLBs before releasing backing store") Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Signed-off-by: Mauro Carvalho Chehab mchehab@kernel.org --- drivers/gpu/drm/i915/gt/intel_gt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c index 034182f85501..7965a77e5046 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt.c +++ b/drivers/gpu/drm/i915/gt/intel_gt.c @@ -1191,10 +1191,10 @@ void intel_gt_invalidate_tlbs(struct intel_gt *gt) if (GRAPHICS_VER(i915) == 12) { regs = gen12_regs; num = ARRAY_SIZE(gen12_regs); - } else if (GRAPHICS_VER(i915) >= 8 && GRAPHICS_VER(i915) <= 11) { + } else if (GRAPHICS_VER(i915) > 8 && GRAPHICS_VER(i915) <= 11) { regs = gen8_regs; num = ARRAY_SIZE(gen8_regs); - } else if (GRAPHICS_VER(i915) < 8) { + } else if (GRAPHICS_VER(i915) <= 8) { return; }