X freezes for a second or every now and then when lid closed

[Joel Fernandes]

On Sat, Oct 27, 2018 at 12:38:56AM -0700, Joel Fernandes wrote:
> Hi!
> My Linux laptop running kernel v4.17 freezes intermittently when the laptop
> lid is closed but external monitors are connected to 2 HDMI ports. I provided
> details on the issue, any idea what could be causing it?
> 
> I ruled out many different subsystems by trial and error, finally I enabled
> ftrace events on power subsystem and see that the freeze is precisely at the
> same time as drm_mode_getconnector is called on these events and its the Xorg
> process. I think since Xorg is busy on this drm_mode_getconnector ioctl, its
> not able to perform its duties.
> 
> I get a stacktrace like so:
> 	    Xorg-1285  [001] ....   801.156606: pm_qos_update_request:
> 	         pm_qos_class=CPU_DMA_LATENCY value=-1
> 	    Xorg-1285  [001] ....   801.156607: pm_qos_update_target:
> 	         action=UPDATE_REQ prev_value=0 curr_value=2000000000
> 	    Xorg-1285  [001] ....   801.156609: <stack trace>
>  => pm_qos_update_target
>  => intel_dp_aux_xfer
>  => intel_dp_aux_transfer
>  => drm_dp_dpcd_access
>  => drm_dp_dpcd_read
>  => intel_dp_read_dpcd
>  => intel_dp_detect
>  => drm_helper_probe_single_connector_modes
>  => drm_mode_getconnector
>  => drm_ioctl_kernel
>  => drm_ioctl
>  => do_vfs_ioctl
>  => ksys_ioctl
>  => __x64_sys_ioctl
>  => do_syscall_64
>  => entry_SYSCALL_64_after_hwframe
> 
> The X version I'm running is X.Org X Server 1.19.6
> 
> I also see these in /var/log/Xorg.0.log every 30 seconds and it seems
> correlated to the time of freezing:
> [  1141.925] (--) modeset(0): HDMI max TMDS frequency 170000KHz
> [  1142.223] (II) modeset(0): EDID vendor "HWP", prod id 13093
> [  1142.223] (II) modeset(0): Using hsync ranges from config file
> [  1142.223] (II) modeset(0): Using vrefresh ranges from config file
> [  1142.223] (II) modeset(0): Printing DDC gathered Modelines:
> [  1142.223] (II) modeset(0): Modeline "1920x1080"x0.0  148.50  1920 2008
> 2052 2200  1080 1084 1089 1125 +hsync +vsync (67.5 kHz eP)
> [  1142.223] (II) modeset(0): Modeline "1920x1080"x0.0  148.50  1920 2448
> 2492 2640  1080 1084 1089 1125 +hsync +vsync (56.2 kHz e)
> 
> Let me know if you spot anything weird, and if you have any suggestions?

Just for documenting it, the issue seems very similar to what is reported in
this comment:
https://forums.linuxmint.com/viewtopic.php?t=253475#p1457587 

I am indeed using Cinammon as well. With the lid closed, the same 'modeset'
log messages appear and freeze the system every 30 seconds.

- Joel