Can this model be dropped from MICROCODE_BLACKLIST_DEFAULT? It was originally added because certain microcode revisions may cause a hang if they are loaded late. However, the linux kernel contains a workaround to prevent that from happening, which is present in all current stable releases (originally added in 4.14), and also the microcode for this model has now been updated to a later version which doesn't have this issue anyway. I have this model, and currently have to override MICROCODE_BLACKLIST_DEFAULT in my profile to get microcode updates.
At best, you will get upstream convinced to lift that restriction -- upstream is still putting file aside to prevent automatic installation, see https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files/tree/microcode-20200616/intel-ucode-with-caveats. And we do the same with MICROCODE_BLACKLIST_DEFAULT which can be altered via package.env entry. Regarding kernel: Could you please name the required kernel change (commit)? We would to have ensure that this is present in all supported (=stabilized) LTS kernels.
The first mainline commit to fix this was https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=723f2828a98c8ca19842042f418fb30dd8cfc0f7 which landed in 4.14. There were some subsequent commits to target it more precisely in 4.15. Jia Zhang (2): * [b94b73733171] x86/microcode/intel: Extend BDW late-loading with a revision check * [7e702d17ed13] x86/microcode/intel: Extend BDW late-loading further with LLC size check 4.4.y backports: [da0933ceec96] x86/microcode/intel: Disable late loading on model 79 [7d1bef0f6037] x86/microcode/intel: Extend BDW late-loading with a revision check [20c0a0428449] x86/microcode/intel: Extend BDW late-loading further with LLC size check 4.9.y backports: [ca9601382b31] x86/microcode/intel: Disable late loading on model 79 [431fd501aa3f] x86/microcode/intel: Extend BDW late-loading with a revision check [9f3a6cadf494] x86/microcode/intel: Extend BDW late-loading further with LLC size check 4.14.y backports: [d98309da07fd] x86/microcode/intel: Extend BDW late-loading with a revision check [ac2cc8876538] x86/microcode/intel: Extend BDW late-loading further with LLC size check
I created an issue for Intel https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files/issues/40 Let's see what they say about changing the repository.
There was an update on the GitHub issue. It seems the error relates to whether the processor is currently running b000021 or later, not what the new update version is. So Intel can't remove the caveat. The kernel code though does check for what the processor is currently running, so this shouldn't be an issue for linux.
