On Thu, May 29, 2025 at 04:40:01PM -0700, Sean Christopherson wrote: >On a userspace MSR filter change, recalculate all MSR intercepts using the >filter-agnostic logic instead of maintaining a "shadow copy" of KVM's >desired intercepts. The shadow bitmaps add yet another point of failure, >are confusing (e.g. what does "handled specially" mean!?!?), an eyesore, >and a maintenance burden. > >Given that KVM *must* be able to recalculate the correct intercepts at any >given time, and that MSR filter updates are not hot paths, there is zero >benefit to maintaining the shadow bitmaps. > >Link: https://lore.kernel.org/all/aCdPbZiYmtni4Bjs@xxxxxxxxxx >Link: https://lore.kernel.org/all/20241126180253.GAZ0YNTdXH1UGeqsu6@fat_crate.local >Cc: Borislav Petkov <bp@xxxxxxxxx> >Cc: Xin Li <xin@xxxxxxxxx> >Cc: Chao Gao <chao.gao@xxxxxxxxx> >Cc: Dapeng Mi <dapeng1.mi@xxxxxxxxxxxxxxx> >Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> Reviewed-by: Chao Gao <chao.gao@xxxxxxxxx> one nit below, >+ >+ if (vcpu->arch.xfd_no_write_intercept) >+ vmx_disable_intercept_for_msr(vcpu, MSR_IA32_XFD, MSR_TYPE_RW); >+ >+ Remove one newline here.
