<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [CI][DRMTIP] igt@gem_ppgtt@blt-vs-render-ctx0 - dmesg-fail - BUG: unable to handle kernel paging request at ffffa08d71663ee0" href="https://bugs.freedesktop.org/show_bug.cgi?id=109823#c4">Comment # 4</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [CI][DRMTIP] igt@gem_ppgtt@blt-vs-render-ctx0 - dmesg-fail - BUG: unable to handle kernel paging request at ffffa08d71663ee0" href="https://bugs.freedesktop.org/show_bug.cgi?id=109823">bug 109823</a> from <a class="email" href="mailto:chris@chris-wilson.co.uk" title="Chris Wilson <chris@chris-wilson.co.uk>"> Chris Wilson</a> <pre>If it's stray memcorruption (honestly more likely than a bug in the swap code), then commit e781a7a3235e9ff68095d2cd4d9c1e039a0516d7 Author: Chris Wilson <<a href="mailto:chris@chris-wilson.co.uk">chris@chris-wilson.co.uk</a>> Date: Mon Mar 4 11:41:13 2019 +0000 drm/i915: Acquire breadcrumb ref before cancelling We may race the interrupt signaling with retirement, in which case the order in which we acquire the reference inside the interrupt is vital to provide the correct barrier against the request being freed in retirement, i.e. we need to acquire our reference before marking the breadcrumb as cancelled (as soon as the breadcrumb is cancelled retirement may drop its reference to the request without serialisation with the interrupt handler). is definitely a possible fix. But without definite proof, the only thing we can do is read the code while waiting for a pattern.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> <li>You are the QA Contact for the bug.</li> <li>You are on the CC list for the bug.</li> </ul> </body> </html>