#regzbot introduced: v6.12.34..v6.12.35
After upgrade to kernel 6.12.35, vfio passthrough for my GPU has stopped working within a windows VM, it sees device in device manager but reports that it did not start correctly. I compared lspci logs in the vm before and after upgrade to 6.12.35, and here are the changes I noticed:
- the reported link speed for the passthrough GPU has changed from 2.5 to 16GT/s - the passthrough GPU has lost it's 'BusMaster' and MSI enable flags - latency measurement feature appeared
These entries also began appearing within the vm in dmesg when host kernel is 6.12.35 or above:
[ 1.963177] nouveau 0000:01:00.0: sec2(gsp): mbox 1c503000 00000001 [ 1.963296] nouveau 0000:01:00.0: sec2(gsp):booter-load: boot failed: -5 ... [ 1.964580] nouveau 0000:01:00.0: gsp: init failed, -5 [ 1.964641] nouveau 0000:01:00.0: init failed with -5 [ 1.964681] nouveau: drm:00000000:00000080: init failed with -5 [ 1.964721] nouveau 0000:01:00.0: drm: Device allocation failed: -5 [ 1.966318] nouveau 0000:01:00.0: probe with driver nouveau failed with error -5
6.12.34 worked fine, and latest 6.12 LTS does not work either. I am using intel CPU and nvidia GPU (for passthrough, and as my GPU on linux system).