6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sean Christopherson seanjc@google.com
[ Upstream commit 27c4fa42b11af780d49ce704f7fa67b3c2544df4 ]
Check for pending (and notified!) posted interrupts when checking if L2 has a pending wake event, as fully posted/notified virtual interrupt is a valid wake event for HLT.
Note that KVM must check vmx->nested.pi_pending to avoid prematurely waking L2, e.g. even if KVM sees a non-zero PID.PIR and PID.0N=1, the virtual interrupt won't actually be recognized until a notification IRQ is received by the vCPU or the vCPU does (nested) VM-Enter.
Fixes: 26844fee6ade ("KVM: x86: never write to memory from kvm_vcpu_check_block()") Cc: stable@vger.kernel.org Cc: Maxim Levitsky mlevitsk@redhat.com Reported-by: Jim Mattson jmattson@google.com Closes: https://lore.kernel.org/all/20231207010302.2240506-1-jmattson@google.com Link: https://lore.kernel.org/r/20240607172609.3205077-5-seanjc@google.com Signed-off-by: Sean Christopherson seanjc@google.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kvm/vmx/nested.c | 36 ++++++++++++++++++++++++++++++++++-- 1 file changed, 34 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 5f85375f75b48..0ad66b9207e85 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -3965,8 +3965,40 @@ static bool nested_vmx_preemption_timer_pending(struct kvm_vcpu *vcpu)
static bool vmx_has_nested_events(struct kvm_vcpu *vcpu, bool for_injection) { - return nested_vmx_preemption_timer_pending(vcpu) || - to_vmx(vcpu)->nested.mtf_pending; + struct vcpu_vmx *vmx = to_vmx(vcpu); + void *vapic = vmx->nested.virtual_apic_map.hva; + int max_irr, vppr; + + if (nested_vmx_preemption_timer_pending(vcpu) || + vmx->nested.mtf_pending) + return true; + + /* + * Virtual Interrupt Delivery doesn't require manual injection. Either + * the interrupt is already in GUEST_RVI and will be recognized by CPU + * at VM-Entry, or there is a KVM_REQ_EVENT pending and KVM will move + * the interrupt from the PIR to RVI prior to entering the guest. + */ + if (for_injection) + return false; + + if (!nested_cpu_has_vid(get_vmcs12(vcpu)) || + __vmx_interrupt_blocked(vcpu)) + return false; + + if (!vapic) + return false; + + vppr = *((u32 *)(vapic + APIC_PROCPRI)); + + if (vmx->nested.pi_pending && vmx->nested.pi_desc && + pi_test_on(vmx->nested.pi_desc)) { + max_irr = pi_find_highest_vector(vmx->nested.pi_desc); + if (max_irr > 0 && (max_irr & 0xf0) > (vppr & 0xf0)) + return true; + } + + return false; }
/*