Hello Ray, from the "Code:" line you supplied I think the segfault happens in create_cache_trans at ../src/mesa/state_tracker/st_cb_bitmap.c:402.
https://sources.debian.org/src/mesa/20.3.5-1/src/mesa/state_tracker/st_cb_bitmap.c/#L402 But I guess this information is not enough for the maintiner, to find out what inputs causing the segfault in this function. Maybe you could install systemd-coredump and deliver the output of 'journalctl --no-pager' following the last segfault line, that appears in dmesg too. More details are in this link: https://wiki.debian.org/HowToGetABacktrace Kind regards, Bernhard
https://wiki.debian.org/InterpretingKernelOutputAtProcessCrash From submitter: [406058.660546] openuniverse[242638]: segfault at 20 ip 00007f86f454ad63 sp 00007ffefd7050a0 error 4 in nouveau_dri.so[7f86f4517000+d46000] [406058.660565] Code: 48 48 89 c7 b9 02 00 00 00 ff 90 08 03 00 00 4c 8b 54 24 10 be ff 00 00 00 48 89 c7 49 89 82 70 12 00 00 49 8b 82 60 12 00 00 <8b> 50 20 c1 e2 05 e8 52 c9 fc ff 4c 8b 54 24 10 48 89 ea 4c 89 fe "error 4" == 0b100 0: no page found 0: read access 1: user-mode access echo -n "find /b ..., ..., 0x" && \ echo "48 48 89 c7 b9 02 00 00 00 ff 90 08 03 00 00 4c 8b 54 24 10 be ff 00 00 00 48 89 c7 49 89 82 70 12 00 00 49 8b 82 60 12 00 00 <8b> 50 20 c1 e2 05 e8 52 c9 fc ff 4c 8b 54 24 10 48 89 ea 4c 89 fe" \ | sed 's/[<>]//g' | sed 's/ /, 0x/g' find /b ..., ..., 0x48, 0x48, 0x89, 0xc7, 0xb9, 0x02, 0x00, 0x00, 0x00, 0xff, 0x90, 0x08, 0x03, 0x00, 0x00, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0xbe, 0xff, 0x00, 0x00, 0x00, 0x48, 0x89, 0xc7, 0x49, 0x89, 0x82, 0x70, 0x12, 0x00, 0x00, 0x49, 0x8b, 0x82, 0x60, 0x12, 0x00, 0x00, 0x8b, 0x50, 0x20, 0xc1, 0xe2, 0x05, 0xe8, 0x52, 0xc9, 0xfc, 0xff, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0x48, 0x89, 0xea, 0x4c, 0x89, 0xfe # single-use Bullseye/testing amd64 qemu VM 2021-04-14 echo "set enable-bracketed-paste off" >> /etc/inputrc; bash apt update # to speedup testing mv /etc/manpath.config /etc/manpath.config.renamed apt install libeatmydata1 export LD_PRELOAD=/usr/lib/$(uname -m)-linux-gnu/libeatmydata.so apt dist-upgrade apt install gdb libgl1-mesa-dri \ coreutils-dbgsym libgl1-mesa-dri-dbgsym . gdb -q set width 0 set pagination off file /bin/ls tb main run call dlopen("/usr/lib/x86_64-linux-gnu/dri/nouveau_dri.so",0x102) info share find /b 0x00007ffff67c3160, 0x00007ffff750504e, 0x48, 0x48, 0x89, 0xc7, 0xb9, 0x02, 0x00, 0x00, 0x00, 0xff, 0x90, 0x08, 0x03, 0x00, 0x00, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0xbe, 0xff, 0x00, 0x00, 0x00, 0x48, 0x89, 0xc7, 0x49, 0x89, 0x82, 0x70, 0x12, 0x00, 0x00, 0x49, 0x8b, 0x82, 0x60, 0x12, 0x00, 0x00, 0x8b, 0x50, 0x20, 0xc1, 0xe2, 0x05, 0xe8, 0x52, 0xc9, 0xfc, 0xff, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0x48, 0x89, 0xea, 0x4c, 0x89, 0xfe b * (0x7ffff67f3d39 + 42) benutzer@debian:~$ gdb -q (gdb) set width 0 (gdb) set pagination off (gdb) file /bin/ls Reading symbols from /bin/ls... Reading symbols from /usr/lib/debug/.build-id/64/61a544c35b9dc1d172d1a1c09043e487326966.debug... (gdb) tb main Temporary breakpoint 1 at 0x4760: file src/ls.c, line 1622. (gdb) run Starting program: /usr/bin/ls [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". Temporary breakpoint 1, main (argc=1, argv=0x7fffffffe628) at src/ls.c:1622 1622 src/ls.c: Datei oder Verzeichnis nicht gefunden. (gdb) call dlopen("/usr/lib/x86_64-linux-gnu/dri/nouveau_dri.so",0x102) $1 = (void *) 0x55555557a980 (gdb) find /b ..., ..., 0x48, 0x48, 0x89, 0xc7, 0xb9, 0x02, 0x00, 0x00, 0x00, 0xff, 0x90, 0x08, 0x03, 0x00, 0x00, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0xbe, 0xff, 0x00, 0x00, 0x00, 0x48, 0x89, 0xc7, 0x49, 0x89, 0x82, 0x70, 0x12, 0x00, 0x00, 0x49, 0x8b, 0x82, 0x60, 0x12, 0x00, 0x00, 0x8b, 0x50, 0x20, 0xc1, 0xe2, 0x05, 0xe8, 0x52, 0xc9, 0xfc, 0xff, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0x48, 0x89, 0xea, 0x4c, 0x89, 0xfe A syntax error in expression, near `..., ..., 0x48, 0x48, 0x89, 0xc7, 0xb9, 0x02, 0x00, 0x00, 0x00, 0xff, 0x90, 0x08, 0x03, 0x00, 0x00, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0xbe, 0xff, 0x00, 0x00, 0x00, 0x48, 0x89, 0xc7, 0x49, 0x89, 0x82, 0x70, 0x12, 0x00, 0x00, 0x49, 0x8b, 0x82, 0x60, 0x12, 0x00, 0x00, 0x8b, 0x50, 0x20, 0xc1, 0xe2, 0x05, 0xe8, 0x52, 0xc9, 0xfc, 0xff, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0x48, 0x89, 0xea, 0x4c, 0x89, 0xfe'. (gdb) info share From To Syms Read Shared Object Library ... 0x00007ffff67c3160 0x00007ffff750504e Yes /usr/lib/x86_64-linux-gnu/dri/nouveau_dri.so ... (*): Shared library is missing debugging information. (gdb) find /b 0x00007ffff67c3160, 0x00007ffff750504e, 0x48, 0x48, 0x89, 0xc7, 0xb9, 0x02, 0x00, 0x00, 0x00, 0xff, 0x90, 0x08, 0x03, 0x00, 0x00, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0xbe, 0xff, 0x00, 0x00, 0x00, 0x48, 0x89, 0xc7, 0x49, 0x89, 0x82, 0x70, 0x12, 0x00, 0x00, 0x49, 0x8b, 0x82, 0x60, 0x12, 0x00, 0x00, 0x8b, 0x50, 0x20, 0xc1, 0xe2, 0x05, 0xe8, 0x52, 0xc9, 0xfc, 0xff, 0x4c, 0x8b, 0x54, 0x24, 0x10, 0x48, 0x89, 0xea, 0x4c, 0x89, 0xfe 0x7ffff67f3d39 <st_Bitmap+489> 1 pattern found. (gdb) b * (0x7ffff67f3d39 + 42) Breakpoint 2 at 0x7ffff67f3d63: file ../src/mesa/state_tracker/st_cb_bitmap.c, line 402. (gdb) info b Num Type Disp Enb Address What 2 breakpoint keep y 0x00007ffff67f3d63 in create_cache_trans at ../src/mesa/state_tracker/st_cb_bitmap.c:402 https://sources.debian.org/src/mesa/20.3.5-1/src/mesa/state_tracker/st_cb_bitmap.c/#L402
