black stripes in X/Xwayland applications under panfrost/midgard
Initially mentioned in #4471 but creating independent ticket so it doesn't get lost.
After upgrade to Mesa 21.1.0-rc1 on RK3399 there seems to be a regression in X applications (behavior is consistent in both pure X and Xwayland) manifesting in random black stripes/rectangles:
I find GIMP to be the easiest reproducer.
Followed suggestion in #4471 and dumped pandecode files from Xephyr but despite being able to reproduce issue, none of files had Fault Pointer other than 0x0.
Also note that faults started to appear in dmesg:
[ 4377.085001] panfrost ff9a0000.gpu: Unhandled Page fault in AS1 at VA 0x00000000050EF600
Reason: TODO
raw fault status: 0x660003C3
decoded fault status: SLAVE FAULT
exception type 0xC3: TRANSLATION_FAULT_LEVEL3
access type 0x3: WRITE
source id 0x6600
[ 4377.094385] panfrost ff9a0000.gpu: Unhandled Page fault in AS1 at VA 0x00000000050EF600
Reason: TODO
raw fault status: 0x660003C3
decoded fault status: SLAVE FAULT
exception type 0xC3: TRANSLATION_FAULT_LEVEL3
access type 0x3: WRITE
source id 0x6600
[ 4377.119769] panfrost ff9a0000.gpu: Unhandled Page fault in AS1 at VA 0x00000000050EF600
Reason: TODO
raw fault status: 0x660003C3
decoded fault status: SLAVE FAULT
exception type 0xC3: TRANSLATION_FAULT_LEVEL3
access type 0x3: WRITE
source id 0x6600