Bug#1052069: ways to proceed?

[Andreas Beckmann]

On 12/11/2023 15.21, Adam Majer wrote:
> On 2023-11-10 10:51, Andreas Beckmann wrote:
>>> The module should continue to work on 6.1
>>> The module should continue to work on 6.5 booted with ibt=off
>>> The module should fail to load with an error message describing the 
>>> issue on 6.5 with ibt enabled, but without a kernel BUG.
>>
>> Did you find some time to test the package patched with my IBT related 
>> changes?
> 
> I've managed to add the patch today and recompile. Complete success and 
> works as expected. It no longer crashes when ibt=on.
> 
> Initially I've had an idea to automatically set this kernel command line 
> boot values when the module is installed, but having this informative 

Theoretically I could have patched the module to disable IBT at runtime 
while loading the incompatible module ... but I doubt that silently* 
lowering the system security level is a good idea ... that should rather 
be admin's choice. Also, this behavioral change wouldn't exist in any 
other distro.

*) silently includes kprint("LOWERING SECURITY LEVEL BY DISABLING IBT TO 
LOAD PROPRIETARY LEGACY KERNEL MODULE")

> message is actually better. One nit-pick is that the kernel message is 
> not clear as to what module it's talking about.
> 
> kernel: NVRM: This module is incompatible with IBT. Try booting with 
> ibt=off.
> 
> A better message could be,
> 
> kernel: NVRM: This Nvidia driver is incompatible with IBT. Try booting 
> with ibt=off.

Thanks for the feedback, I'll update the error message and apply this 
patch to all driver series up to 470. (This does not seem to be fixed in 
470.223.02, and maybe upstream will never provide an IBT-enabled build 
for the old driver series. The percentage of people running a modern cpu 
with a legacy gpu is probably very low.)

Andreas