[mi] EQ overflowing.  Additional events will be discarded until existing events are processed.

Backtrace:
0: /usr/bin/X (xorg_backtrace+0x48) [0x557f47042848]
1: /usr/bin/X (mieqEnqueue+0x22b) [0x557f4702483b]
2: /usr/bin/X (QueuePointerEvents+0x52) [0x557f46f05f72]
3: /usr/lib/xorg/modules/input/synaptics_drv.so (0x7fa562bcd000+0x4f48) [0x7fa562bd1f48]
4: /usr/lib/xorg/modules/input/synaptics_drv.so (0x7fa562bcd000+0x68e2) [0x7fa562bd38e2]
5: /usr/bin/X (0x557f46e99000+0x93518) [0x557f46f2c518]
6: /usr/bin/X (0x557f46e99000+0xbbc90) [0x557f46f54c90]
7: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7fa56ac50000+0x10330) [0x7fa56ac60330]
8: /usr/bin/X (0x557f46e99000+0x1ad990) [0x557f47046990]
9: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7fa56ac50000+0x10330) [0x7fa56ac60330]
10: /lib/x86_64-linux-gnu/libc.so.6 (ioctl+0x7) [0x7fa56975f1e7]
11: /usr/lib/x86_64-linux-gnu/libdrm.so.2 (drmIoctl+0x34) [0x7fa56aa46144]
12: /usr/lib/xorg/modules/drivers/intel_drv.so (0x7fa5656b9000+0x6352c) [0x7fa56571c52c]
13: /usr/lib/xorg/modules/drivers/intel_drv.so (0x7fa5656b9000+0x63f9d) [0x7fa56571cf9d]
14: /usr/bin/X (xf86DPMSSet+0x6f) [0x557f46f6288f]
15: /usr/bin/X (xf86SaveScreen+0x4a) [0x557f46f6296a]
16: /usr/bin/X (dixSaveScreens+0x215) [0x557f46f1da05]
17: /usr/bin/X (mieqProcessInputEvents+0x166) [0x557f47024dc6]
18: /usr/bin/X (ProcessInputEvents+0x9) [0x557f46f2c679]
19: /usr/bin/X (0x557f46e99000+0x55d16) [0x557f46eeed16]
20: /usr/bin/X (0x557f46e99000+0x59d9a) [0x557f46ef2d9a]
21: /lib/x86_64-linux-gnu/libc.so.6 (__libc_start_main+0xf5) [0x7fa56968ff45]
22: /usr/bin/X (0x557f46e99000+0x451ee) [0x557f46ede1ee]

[mi] These backtraces from mieqEnqueue may point to a culprit higher up the stack.
[mi] mieq is *NOT* the cause.  It is a victim.
BUG: triggered 'if (priv->num_active_touches == 0)'
BUG: ../../src/synaptics.c:2839 in UpdateTouchState()

Backtrace:
0: /usr/bin/X (xorg_backtrace+0x48) [0x557f47042848]
1: /usr/lib/xorg/modules/input/synaptics_drv.so (0x7fa562bcd000+0x2dc4) [0x7fa562bcfdc4]
2: /usr/lib/xorg/modules/input/synaptics_drv.so (0x7fa562bcd000+0x5070) [0x7fa562bd2070]
3: /usr/lib/xorg/modules/input/synaptics_drv.so (0x7fa562bcd000+0x68e2) [0x7fa562bd38e2]
4: /usr/bin/X (0x557f46e99000+0x93518) [0x557f46f2c518]
5: /usr/bin/X (0x557f46e99000+0xbbc90) [0x557f46f54c90]
6: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7fa56ac50000+0x10330) [0x7fa56ac60330]
7: /lib/x86_64-linux-gnu/libc.so.6 (__select+0x33) [0x7fa56975fc53]
8: /usr/bin/X (WaitForSomething+0x1ac) [0x557f4703fd8c]
9: /usr/bin/X (0x557f46e99000+0x55c61) [0x557f46eeec61]
10: /usr/bin/X (0x557f46e99000+0x59d9a) [0x557f46ef2d9a]
11: /lib/x86_64-linux-gnu/libc.so.6 (__libc_start_main+0xf5) [0x7fa56968ff45]
12: /usr/bin/X (0x557f46e99000+0x451ee) [0x557f46ede1ee]