<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEEDINFO " title="NEEDINFO - LCD flickering on Thinkpad T440p (Haswell) with kernel 4.6-rc4 (PSR enabled)" href="https://bugs.freedesktop.org/show_bug.cgi?id=95176#c39">Comment # 39</a> on <a class="bz_bug_link bz_status_NEEDINFO " title="NEEDINFO - LCD flickering on Thinkpad T440p (Haswell) with kernel 4.6-rc4 (PSR enabled)" href="https://bugs.freedesktop.org/show_bug.cgi?id=95176">bug 95176</a> from <a class="email" href="mailto:calvin.walton@kepstin.ca" title="Calvin Walton <calvin.walton@kepstin.ca>"> Calvin Walton</a> <pre>When I re-enable the internal display on my T440p I have the following display configuration: - eDP internal display (1920x1080) - Thinkpad Ultra dock |- DP monitor (2560x1440) \- HDMI monitor (1920x1080) Immediately after enabling this configuration, the kernel log printed: [17481.417387] [drm:intel_set_cpu_fifo_underrun_reporting] *ERROR* uncleared fifo underrun on pipe B [17481.417392] [drm:intel_cpu_fifo_underrun_irq_handler] *ERROR* CPU pipe B FIFO underrun (I don't presently have any debug logging enabled, will retest with that later) and the external DP monitor started blanking out for longish periods of time, up to several seconds (moving the mouse would usually cause the picture to re-appear. The external HDMI monitor didn't blank completely, but did appear to lose sync or display corrupted picture - e.g. horizontal offset, shaking picture. Disabling psr (with the option i915.enable_psr=0 option) fixes this completely.</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>