Created attachment 116079 [details] journalctl output for crash Switching my DisplayPort attached monitor on (or off and then on again) while booted to multiuser target (no Xorg or Wayland) causes a kernel Oops, followed by soft-lockups which render the system unusable. Doing the same while at the full Graphical target causes gnome-shell to crash, but it is possible to recover the system by logging in again. The kernel error and IP are: >May 24 23:25:28 fedora-workstation.home kernel: BUG: unable to handle kernel NULL pointer dereference at 00000000000003b0 >May 24 23:25:28 fedora-workstation.home kernel: IP: [<ffffffffa0152055>] radeon_connector_edid+0x5/0x70 [radeon] Full journal from a reproduction of the bug will be attached, as will lspci -nn. I have isolated this using git bisect to the following commit (the patch for which is attached to this bug). This is a commit currently part of the linux-stable tree and lies between 4.0.2 and 4.0.3 >016a255b7835ee7e49a3eba3c14ba0bc0221a4f8 is the first bad commit >commit 016a255b7835ee7e49a3eba3c14ba0bc0221a4f8 >Author: Alex Deucher <alexander.deucher@amd.com> >Date: Tue Apr 7 09:52:42 2015 -0400 > > drm/radeon: only mark audio as connected if the monitor supports it (v3) > > commit 0f55db36d49d45b80eff0c0a2a498766016f458b upstream. > > Otherwise the driver may try and send audio which may confuse the > monitor. > > v2: set pin to NULL if no audio > v3: avoid crash with analog encoders > > Signed-off-by: Alex Deucher <alexander.deucher@amd.com> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>> > >:040000 040000 de0366a6790f5c91d175bcb89cb34956bbe72b26 >bbdb5734961f824558152c7c34a840c78bc3a9a9 M drivers
Created attachment 116080 [details] lspci -nn
Created attachment 116081 [details] Oops stack trace only
Created attachment 116082 [details] Bisection log
Created attachment 116083 [details] [review] Culprit commit according to bisect Sorry for the bug-spam, I wasn't sure how to add many attachments at once.
Created attachment 116085 [details] [review] possible fix Does the attached patch fix the issue?
Actually reverting the commit is probably the proper fix.
Patch fixes the issue, I can try a revert as well. With the patch applied, there's still a problem with gnome-shell crashing, but there's no Oops in the VT any more.
(In reply to Alex Deucher from comment #6) > Actually reverting the commit is probably the proper fix. Reverting the commit doesn't fix the issue, there is still a kernel Oops upon hotplugging the monitor. I'll dig into the trace.
How about the revert and the patch?
(In reply to Alex Deucher from comment #9) > How about the revert and the patch? Revert and patch is working for me.
Is this fixed? I am asking because 91253 is probably due to the same committ.
problematic commit reverted: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=2d1c18bba15daf89d75ce475ecd2068f483aa12f Fix committed: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=fbfd3bc7dfd7efcad2d2e52bf634f84c80a77a35
Will this be in 4.2 rc3?
(In reply to Andreas Tunek from comment #13) > Will this be in 4.2 rc3? Yes, they are in 4.1 as well.
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