Messages in this thread | | | From | Jim Mattson <> | Date | Mon, 6 Dec 2021 20:49:02 -0800 | Subject | Re: [PATCH] KVM: x86: Always set kvm_run->if_flag |
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On Mon, Dec 6, 2021 at 8:31 PM Marc Orr <marcorr@google.com> wrote: > > The kvm_run struct's if_flag is apart of the userspace/kernel API. The
Typo: 'a part'.
> SEV-ES patches failed to set this flag because it's no longer needed by > QEMU (according to the comment in the source code). However, other > hypervisors may make use of this flag. Therefore, set the flag for > guests with encrypted regiesters (i.e., with guest_state_protected set).
Typo: 'registers'.
> Fixes: f1c6366e3043 ("KVM: SVM: Add required changes to support intercepts under SEV-ES") > Signed-off-by: Marc Orr <marcorr@google.com> > ---
> - /* > - * if_flag is obsolete and useless, so do not bother > - * setting it for SEV-ES guests. Userspace can just > - * use kvm_run->ready_for_interrupt_injection. > - */ > - kvm_run->if_flag = !vcpu->arch.guest_state_protected > - && (kvm_get_rflags(vcpu) & X86_EFLAGS_IF) != 0; > - > + kvm_run->if_flag = static_call(kvm_x86_get_if_flag)(vcpu);
I'm sorry that I missed that change when it first went by. Maintaining backwards compatibility with existing userspace code is a fundamental tenet of Linux kernel development.
Acked-by: Jim Mattson <jmattson@google.com>
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