On 17/10/2023 12:10, Aaron Puchert wrote:
Am 13.10.23 um 02:36 schrieb Robin Klitscher:
/usr/src/kernel-modules/nvidia-535.113.01-default/nvidia.o: warning: objtool: _nv042750rm+0x4f: 'naked' return found in RETHUNK build
Looks like the retpoline validation complaining. Retpolines are a workaround to mitigate the Spectre v2 CPU speculation side-attack channel. [1] The validation checks compiled object files for the proper return instruction sequence.
I have no idea whether this is expected or not, since I don't use the nVidia drivers, but I would check if the involved packages are up to date. The driver looks fine (just to make sure, check the version of nvidia-driver-G06-kmp-default specifically), but check that kernel-devel and kernel-default-devel match your kernel version, and gcc is up to date. Not sure if anything else might be relevant.
Also, did you do any changes related to CPU vulnerability mitigations?
If everything is up to date, I would suggest to file a bug. The mailing list isn't the right place for such a specific issue that doesn't break anything.
Aaron
[1] <https://en.wikipedia.org/wiki/Spectre_(security_vulnerability)#Mitigation>
Thank you for taking the trouble. The version of nvidia-driver-G06-kmp-default is confirmed as 535.113.01, which looks OK; while kernel-devel and kernel-default-devel seem properly aligned with the running kernel version at 6.5.6-1. I'm not sure how to establish whether gcc is up to date, but I'd be surprised if it wasn't. And I've not done any changes related to CPU vulnerability mitigations; or at least, none that I know of. So the behaviour remains a mystery, though so far a harmless one. May it remain so. I take your point about filing a bug. If it becomes troublesome I'll do so. -- Robin K Wellington "Harbour City" New Zealand