The following is a copy an issue I posted to drm/i915 gitlab [1] two months ago. I repost it to the mailing lists in hope that it will help the right people pay attention to it. After kernel upgrade from 6.2.13 to 6.3 HDMI connector detection is broken for me. Issue is 100% reproducible: 1. Start system as usual with HDMI connected. 2. Disconnect HDMI 3. Connect HDMI back 4. Get "no signal" on display, connector status in sysfs is disconnected Curiously, running xrandr over ssh like ssh qnap251.local env DISPLAY=:0 xrandr makes display come back. drm-tip tip is affected as well (last test 2023-08-02). Bisecting points at a4e771729a51 ("drm/probe_helper: sort out poll_running vs poll_enabled"). Reverting that commit on top of 6.3 fixes the issue for me. System information: * System architecture: x86_64 * Kernel version: 6.3.arch1 * Linux distribution: Arch Linux * Machine: QNAP TS-251A, CPU: Intel(R) Celeron(R) CPU N3060 @ 1.60GHz * Display connector: single HDMI display * dmesg with debug information (captured on drm-tip, following above 4 steps): [2] * xrandr output: Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384 DP-1 disconnected (normal left inverted right x axis y axis) HDMI-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 708mm x 398mm 1920x1080 60.00*+ 50.00 59.94 30.00 25.00 24.00 29.97 23.98 1920x1080i 60.00 50.00 59.94 1360x768 59.80 1280x768 60.35 1280x720 60.00 50.00 59.94 1024x768 75.03 70.07 60.00 832x624 74.55 800x600 75.00 60.32 720x576 50.00 720x480 60.00 59.94 640x480 75.00 60.00 59.94 720x400 70.08 DP-2 disconnected (normal left inverted right x axis y axis) HDMI-2 disconnected (normal left inverted right x axis y axis)``` I'm willing to provide additional information and/or test fixes. [1] https://gitlab.freedesktop.org/drm/intel/-/issues/8451 [2] https://gitlab.freedesktop.org/drm/intel/uploads/fda7aff0b13ef20962856c2c7be51544/dmesg.txt #regzbot introduced: a4e771729a51 -- Best regards, Mikhail Rudenko