On 26/01/2022 13:37, Andrew Cooper wrote: > On 26/01/2022 12:44, Roger Pau Monné wrote: >> On Wed, Jan 26, 2022 at 08:44:46AM +0000, Andrew Cooper wrote: >>> All AMD IBRS-related features are in CPUID.0x80000008.ebx. Collect them in >>> early_cpu_init() so init_speculative_mitigations() can use them. >>> >>> Rework the existing logic structure to fill in c->extended_cpuid_level and >>> separate out the ambiguous use of ebx in an otherwise 0x80000008-specific >>> logic block. >>> >>> Signed-off-by: Andrew Cooper <[email protected]> >> Reviewed-by: Roger Pau Monné <[email protected]> >> >> It would be good to update the comment ahead of early_cpu_init to >> mention it now also gather speculation-related fields from CPUID in >> order to do early setup of mitigations. >> >> I think you could also use boot_cpu_data in spec_ctrl.c print_details >> instead of fetching again the cpuid leafs? > Hmm - I may have a mistake here. > > Boot time CPUID handling is giant mess, and I haven't had time to finish > my work to make BSP microcode loading dependent on xmalloc(), allowing
Sorry. I mean "independent" here. ~Andrew > it to move far earlier, and removing the early/late CPUID split. > > However, init_speculative_mitigations() is called after late CPUID > setup, so e8b should be suitably collected. Let me try to figure out > what's going on. > > For print_details(), I have a feeling that may have been an artefact of > an early version of the logic, and likely can be cleaned up. > > ~Andrew
