<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_REOPENED " title="REOPENED - [i9xx TV][BISECT] vblank wait timeout on crtc" href="https://bugs.freedesktop.org/show_bug.cgi?id=93782#c32">Comment # 32</a> on <a class="bz_bug_link bz_status_REOPENED " title="REOPENED - [i9xx TV][BISECT] vblank wait timeout on crtc" href="https://bugs.freedesktop.org/show_bug.cgi?id=93782">bug 93782</a> from <a class="email" href="mailto:felix.schwarz@oss.schwarz.eu" title="Felix Schwarz <felix.schwarz@oss.schwarz.eu>"> Felix Schwarz</a> <pre>Created <a href="attachment.cgi?id=128625" name="attach_128625" title="dmesg Linux 4.9 with disabled cxsr hack">attachment 128625</a> <a href="attachment.cgi?id=128625&action=edit" title="dmesg Linux 4.9 with disabled cxsr hack">[details]</a> dmesg Linux 4.9 with disabled cxsr hack (In reply to Maarten Lankhorst from <a href="show_bug.cgi?id=93782#c31">comment #31</a>) > Did anyone here test the patch I provided, for those with >100 us delays in > their pipe updates? Well I think andram did (<a href="show_bug.cgi?id=93782#c15">comment #15</a>, <a href="show_bug.cgi?id=93782#c16">comment #16</a>). I did not comment earlier as andram bisected the problem back to 4.6 change when my problems (and the initial reporter's problem) started much earlier (see <a href="show_bug.cgi?id=93782#c14">comment 14</a>). However just to be sure I applied your patch on top of git commit 69973b83(4.9) but that does not solve the problem for me (traceback attached). I started to bisect the problem on my machine but this a quite time consuming process. First of all the machine itself is quite slow and this hardware is ancient - but I somehow I despise to retire a machine due to a regression in the Linux kernel. However the main problem is that there is no clear "beginning" but there are multiple interleaved issues. At risk of dilluting the focus here is what I found so far: - Linux 4.2 graphics works fine - 4.3.0: first traceback (warning in drm_atomic_check_only) - 4.4-rc1: vblank-wait-timed-out-on-crt1 - 4.4-rc2: vblank-wait-timed-out-on-crt0 With newer kernel versions the symptoms become more severe for me: For example right now (4.8.x) I see multi-second screen freezes during the boot process and whenever the screen is activated (e.g. resuming). However not all computers with this chipset are affected so it seems some of them need some kind of workaround due to connectors, bios, ... One thing I noticed in my dmesg is: > [Firmware Bug]: Duplicate ACPI video bus devices for the same VGA controller, please try module parameter "video.allow_duplicates=1"if the current driver doesn't work. ("video.allow_duplicates=1" does not make any difference for me) My current speculation is that something in the initial atomic conversion broke this specific chip set and this bug is exposed more often as more and more parts of the driver rely on atomic helpers/correct atomic behavior. I'll continue to bisect the bug on my machine but it will take time as I have more pressing issues on my plate.</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>