[Please CC me, I'm not on the list.] Hello, I'm afraid I could use some help. The affected machine froze during a game, was entirely unresponsive locally, though ssh still worked. For completeness' sake, dmesg had: [110592.128512] [drm:amdgpu_job_timedout [amdgpu]] *ERROR* ring sdma0 timeout, signaled seq=3404070, emitted seq=3404071 [110592.128545] [drm:amdgpu_job_timedout [amdgpu]] *ERROR* Process information: process Xorg pid 1191 thread Xorg:cs0 pid 1204 [110592.128549] amdgpu 0000:0c:00.0: GPU reset begin! [110592.138530] [drm:amdgpu_job_timedout [amdgpu]] *ERROR* ring gfx timeout, signaled seq=13149116, emitted seq=13149118 [110592.138577] [drm:amdgpu_job_timedout [amdgpu]] *ERROR* Process information: process Overcooked.exe pid 4830 thread dxvk-submit pid 4856 [110592.138579] amdgpu 0000:0c:00.0: GPU reset begin! Oh well, I thought, and "shutdown -h now" it. That quit my ssh session and locked me out, but otherwise didn't take, no reboot, still frozen. Alt-SysRq-REISUB it was. That did it. Only now all I get is a rescue shell, the pertinent messages look to be [everything is copied off the screen by hand]: [...] BTRFS info [...]: disk space caching is enabled BTRFS info [...]: has skinny extents BTRFS error [...]: bad tree block start, want [big number] have 0 BTRFS error [...]: failed to read block groups: -5 BTRFS error [...]: open_ctree failed Mounting with -o ro,usebackuproot doesn't change anything. running btrfs check gives: checksum verify failed on [same big number] found [8 digits hex] wanted 00000000 checksum verify failed on [same big number] found [8 digits hex] wanted 00000000 bytenr mismatch, want=[same big number], have=0 ERROR: cannot open filesystem. That's all I've got, I'd really appreciate some help. There's hourly snapshots courtesy of Timeshift, though I have a feeling those won't help ... Oh, it's a recent Linux Mint 19.2 install, default layout (@, @home), Timeshift enabled; on a single device (NVMe). HWE kernel (Kernel 5.0.0-31-generic), btrfs-progs 4.15.1. TIA, Christian
