On Thu, Feb 17, 2022 at 11:52 AM Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: > > On 2/17/22 06:30, Leonardo Bras wrote: > > This patchset comes from a bug I found during qemu guest migration from a > > host with newer CPU to a host with an older version of this CPU, and thus > > having less FPU features. > > > > When the guests were created, the one with less features is used as > > config, so migration is possible. > > > > Patch 1 fix a bug that always happens during this migration, and is > > related to the fact that xsave saves all feature flags, but xrstor does > > not touch the PKRU flag. It also changes how fpstate->user_xfeatures > > is set, going from kvm_check_cpuid() to the later called > > kvm_vcpu_after_set_cpuid(). > > > > Patch 2 removes kvm_vcpu_arch.guest_supported_xcr0 since it now > > duplicates guest_fpu.fpstate->user_xfeatures. Some wrappers were > > introduced in order to make it easier to read the replaced version. > > > > Patches were compile-tested, and could fix the bug found. > > Queued, thanks (for 5.17 of course)! For patch 2, I renamed the > function to kvm_guest_supported_xcr0. > > Paolo > That's great! Thanks Paolo!
