<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [SKL]igt/gem_concurrent_blit subcase sporadically causes system hang and *ERROR* blitter: timed out waiting for forcewake ack to clear." href="https://bugs.freedesktop.org/show_bug.cgi?id=89959#c19">Comment # 19</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [SKL]igt/gem_concurrent_blit subcase sporadically causes system hang and *ERROR* blitter: timed out waiting for forcewake ack to clear." href="https://bugs.freedesktop.org/show_bug.cgi?id=89959">bug 89959</a> from <a class="email" href="mailto:mika.kuoppala@intel.com" title="Mika Kuoppala <mika.kuoppala@intel.com>"> Mika Kuoppala</a> <pre>Fast way to reproduce is: gem_concurrent_blit --run-subtest prw-blt-overwrite-source-read-rcs-forked The forcewake ack to clear error messages are misleading as they result from execlist interrupt handler accessing already dead gpu. These items are _less_ likely to be the root cause as I have disabled them selectively without impact on occurrence. - rc6 - dynamic page tables (reproducible with static pdps and aliasing ppgtt) - execlist scheduling/pre-emption (reproducible with 1 slot entry submission) - per ctx bb / pre-emption disabling (Arun's patches are already in) So in the probable list remains: - flush problem (tlb). Forced flushing per ring/bb didn't have impact. - context save/restore corruption. - missing workaround</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are on the CC list for the bug.</li> </ul> </body> </html>