On 8/3/23 02:13, Michal Luczaj wrote:
Anyway, while there, could you take a look at __set_sregs_common()?
*mmu_reset_needed |= kvm_read_cr0(vcpu) != sregs->cr0;
static_call(kvm_x86_set_cr0)(vcpu, sregs->cr0);
vcpu->arch.cr0 = sregs->cr0;
That last assignment seems redundant as both vmx_set_cr0() and svm_set_cr0()
take care of it, but I may be missing something (even if selftests pass with
that line removed).
kvm_set_cr0 assumes that the static call sets vcpu->arch.cr0, so indeed
it can be removed:
static_call(kvm_x86_set_cr0)(vcpu, cr0);
kvm_post_set_cr0(vcpu, old_cr0, cr0);
return 0;
Neither __set_sregs_common nor its callers does not call
kvm_post_set_cr0... Not great, even though most uses of KVM_SET_SREGS
are probably limited to reset in most "usual" VMMs. It's probably
enough to replace this line:
*mmu_reset_needed |= kvm_read_cr0(vcpu) != sregs->cr0;
with a call to the function just before __set_sregs_common returns.
Paolo
