diff options
| author | Sean Christopherson <seanjc@google.com> | 2024-07-19 16:51:00 -0700 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2024-08-29 16:25:05 -0700 |
| commit | 73b42dc69be8564d4951a14d00f827929fe5ef79 (patch) | |
| tree | dbdfebf0206abbc74863931c807e1cad7569fd34 /arch/x86/kvm/svm/svm.c | |
| parent | d33234342f8b468e719e05649fd26549fb37ef8a (diff) | |
KVM: x86: Re-split x2APIC ICR into ICR+ICR2 for AMD (x2AVIC)
Re-introduce the "split" x2APIC ICR storage that KVM used prior to Intel's
IPI virtualization support, but only for AMD. While not stated anywhere
in the APM, despite stating the ICR is a single 64-bit register, AMD CPUs
store the 64-bit ICR as two separate 32-bit values in ICR and ICR2. When
IPI virtualization (IPIv on Intel, all AVIC flavors on AMD) is enabled,
KVM needs to match CPU behavior as some ICR ICR writes will be handled by
the CPU, not by KVM.
Add a kvm_x86_ops knob to control the underlying format used by the CPU to
store the x2APIC ICR, and tune it to AMD vs. Intel regardless of whether
or not x2AVIC is enabled. If KVM is handling all ICR writes, the storage
format for x2APIC mode doesn't matter, and having the behavior follow AMD
versus Intel will provide better test coverage and ease debugging.
Fixes: 4d1d7942e36a ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode")
Cc: stable@vger.kernel.org
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20240719235107.3023592-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86/kvm/svm/svm.c')
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index d8cfe8f23327..eb3de01602b9 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -5053,6 +5053,8 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .enable_nmi_window = svm_enable_nmi_window, .enable_irq_window = svm_enable_irq_window, .update_cr8_intercept = svm_update_cr8_intercept, + + .x2apic_icr_is_split = true, .set_virtual_apic_mode = avic_refresh_virtual_apic_mode, .refresh_apicv_exec_ctrl = avic_refresh_apicv_exec_ctrl, .apicv_post_state_restore = avic_apicv_post_state_restore, |