grub2-mkconfig command could cause unpredictable outcomes for some RHEL 9 minor releases when called with --update-bls-cmdline argument. More information:
https://issues.redhat.com/browse/RHEL-71494
https://issues.redhat.com/browse/RHEL-129314

It looks like RHOSP is not affected (grub2-mkconfig is called there without --update-bls-cmdline), but RHOSO is (vaf architecture, and docs for GPU passthrough as well). And we have customers reporting related problems (case is attached).

I am reporting this issue to ask engineering to consider adding a workaround (I am not sure if RHEL issue is going to be addressed soon), or to ask RHOS PMs to help to prioritize RHEL issue. On top of that we will likely need to provide some recommendations to customers explaining how to address this universally and this is where it also will be useful to get some guidance.

VAF team note: we should only apply a w/a for the time being, until DF team reworks kernel args management for grubby. Then we can switch the implementation and avoid using grub2-mkconfig for edpm-accel-drivers role, architecture DTs and documentation. I am not sure we can simply remove that flag as a solution or a w/a, however, because the impact is unknown, neither the reason we've had it added in the 1st place