Raspberry Pi CMA memory allocation error

[Notwork]

Hello,

The initial problem I ran into was that if I left an LXDE session open on the Pi for 24 hours, it would stop responding
to mouse input. I could move the cursor but the buttons did nothing. There were no messages showing any problems with X, so I
started digging through the log files. After searching the logs I found a message in dmesg that I believe relates to the problem.
This problem only seems to occur when TigerVNC (vncserver) is running.

The error from dmesg is:
$this->bbcode_second_pass_code('', '[39512.548433] alloc_contig_range: [39800, 3a800) PFNs busy
[39512.554387] alloc_contig_range: [36900, 37900) PFNs busy
[39512.560596] alloc_contig_range: [39800, 3a800) PFNs busy
[39512.566190] [drm:vc4_bo_create [vc4]] *ERROR* Failed to allocate from CMA:
[39512.573209] [drm] kernel: 5120kb BOs (1)
[39512.579505] [drm] V3D: 15116kb BOs (15)
[39512.585862] [drm] V3D shader: 120kb BOs (29)
[39512.592241] [drm] dumb: 48kb BOs (3)
[39512.598548] vc4_v3d 3fc00000.v3d: Failed to allocate memory for tile binning: -12.
You may need to enable CMA or give it more memory.')
It looks like I need to add parameters for my config.txt and perhaps my cmdline.txt I am not sure what parameters to add. I have
done some googling but have not found anything to address this specific problem.

My setup:

Hardware: Raspberry Pi 3 Model B
Image: AArch64 - http://os.archlinuxarm.org/os/ArchLinux ... est.tar.gz
Software:
Tiger VNC(vncserver) running on the Pi
Standard X install with xf86-video-fbdev video driver
DE is LXDE

My current config.txt:
$this->bbcode_second_pass_code('', 'enable_uart=1')
My current cmdline.txt:
$this->bbcode_second_pass_code('', '#fsck.repair=yes
fsck.mode=force
')

Thanks for any help.

[Notwork]

Update:

After looking at: https://raspberrypi.stackexchange.com/q ... lit-by-cma, I have made changes to config.txt and cmdline.txt.

new config.txt:
$this->bbcode_second_pass_code('', 'gpu_mem=128
cma_lwm=16
cma_hwm=256
enable_uart=1
')

new cmdline.txt
$this->bbcode_second_pass_code('', '#fsck.repair=yes
fsck.mode=force
coherent_pool=6M smsc95xx.turbo_mode=N
')

So far the error has not recurred and LXDE is working ok.

If the system stays stable for another 24 hours I will mark this as solved.

[Notwork]

Update:

Same error occured again although it took longer for it to recur. LXDE stopped responding to mouse and keyboard input. Since it took longer I am wondering if this issue is being caused by a memory leak?

Not sure where to go from here. Any help would be greatly appreciated.