diff options
| author | Sean Christopherson <seanjc@google.com> | 2024-06-07 20:26:04 +0300 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2024-06-28 18:59:03 +0300 |
| commit | d83c36d822be44db4bad0c43bea99c8908f54117 (patch) | |
| tree | 4f68948ed1ae17e495623266bbd51da924844fc0 /arch/x86/kvm/vmx | |
| parent | 92c1e3cbf0d02916ae0c6fc3b78864dcb77624ad (diff) | |
| download | linux-d83c36d822be44db4bad0c43bea99c8908f54117.tar.xz | |
KVM: nVMX: Add a helper to get highest pending from Posted Interrupt vector
Add a helper to retrieve the highest pending vector given a Posted
Interrupt descriptor. While the actual operation is straightforward, it's
surprisingly easy to mess up, e.g. if one tries to reuse lapic.c's
find_highest_vector(), which doesn't work with PID.PIR due to the APIC's
IRR and ISR component registers being physically discontiguous (they're
4-byte registers aligned at 16-byte intervals).
To make PIR handling more consistent with respect to IRR and ISR handling,
return -1 to indicate "no interrupt pending".
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240607172609.3205077-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86/kvm/vmx')
| -rw-r--r-- | arch/x86/kvm/vmx/nested.c | 5 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/posted_intr.h | 10 |
2 files changed, 13 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 643935a0f70a..8f4db6e8f57c 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -12,6 +12,7 @@ #include "mmu.h" #include "nested.h" #include "pmu.h" +#include "posted_intr.h" #include "sgx.h" #include "trace.h" #include "vmx.h" @@ -3899,8 +3900,8 @@ static int vmx_complete_nested_posted_interrupt(struct kvm_vcpu *vcpu) if (!pi_test_and_clear_on(vmx->nested.pi_desc)) return 0; - max_irr = find_last_bit((unsigned long *)vmx->nested.pi_desc->pir, 256); - if (max_irr != 256) { + max_irr = pi_find_highest_vector(vmx->nested.pi_desc); + if (max_irr > 0) { vapic_page = vmx->nested.virtual_apic_map.hva; if (!vapic_page) goto mmio_needed; diff --git a/arch/x86/kvm/vmx/posted_intr.h b/arch/x86/kvm/vmx/posted_intr.h index 6b2a0226257e..1715d2ab07be 100644 --- a/arch/x86/kvm/vmx/posted_intr.h +++ b/arch/x86/kvm/vmx/posted_intr.h @@ -1,6 +1,8 @@ /* SPDX-License-Identifier: GPL-2.0 */ #ifndef __KVM_X86_VMX_POSTED_INTR_H #define __KVM_X86_VMX_POSTED_INTR_H + +#include <linux/find.h> #include <asm/posted_intr.h> void vmx_vcpu_pi_load(struct kvm_vcpu *vcpu, int cpu); @@ -12,4 +14,12 @@ int vmx_pi_update_irte(struct kvm *kvm, unsigned int host_irq, uint32_t guest_irq, bool set); void vmx_pi_start_assignment(struct kvm *kvm); +static inline int pi_find_highest_vector(struct pi_desc *pi_desc) +{ + int vec; + + vec = find_last_bit((unsigned long *)pi_desc->pir, 256); + return vec < 256 ? vec : -1; +} + #endif /* __KVM_X86_VMX_POSTED_INTR_H */ |