Public bug reported: There is a problem with mainboard Asus M2A-VM. There is no HDMI monitor connected (monitor uses DVI) but the kernel still tries to read the EDID. Thus, dmesg is spammed every 10 seconds with this message: [ 21.383270] [drm:drm_edid_block_valid] *ERROR* Raw EDID: [ 21.383305] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 21.383307] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 21.383310] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 21.383312] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 21.383314] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 21.383317] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 21.383319] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 21.383322] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 21.383324] [ 21.383328] radeon 0000:01:05.0: HDMI-A-1: EDID block 0 invalid. [ 21.383332] [drm:radeon_dvi_detect] *ERROR* HDMI-A-1: probed a monitor but no|invalid EDID
X behaves very jerky because of the load caused by the kernel demanding the EDID every 10 seconds. For more info see https://bugzilla.redhat.com/show_bug.cgi?id=668196 and http://ubuntuforums.org/showthread.php?t=1607778 I found three possible solutions to solve my problem: 1) disable KMS by using the kernel parameter "radeon.modeset=0" Unfortunately, the X server will then segfault after a short time 2) get the kernel source and patch the radeon driver, see http://ubuntuforums.org/showthread.php?t=1607778 (the patch is not from me!) this works, but you have to patch the kernel after every update again 3) execute the command "echo -n N > /sys/module/drm_kms_helper/parameters/poll" This will effectively stop the pollution of the dmesg (and all the quirky X behavior). This option does not exist in kernel 2.6.35 that's why I had update to kernel 2.6.38 It would be fine if the kernel tries to read the EDID only once and then stops trying if it fails (see patch from solution #2). ** Affects: linux (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/722806 Title: Asus M2A-VM: kernel demanding EDID for an unconnected monitor -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
