KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependent

When introduced, IRQFD resampling worked on POWER8 with XICS. However
KVM on POWER9 has never implemented it - the compatibility mode code
("XICS-on-XIVE") misses the kvm_notify_acked_irq() call and the native
XIVE mode does not handle INTx in KVM at all.

This moved the capability support advertising to platforms and stops
advertising it on XIVE, i.e. POWER9 and later.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Anup Patel <anup@brainfault.org>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20220504074807.3616813-1-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 3bd732eaf08725509f7f0991cb359d1c1c7672cc..3f6a5efdbcf0d69c8db41503d35283ca64c1e1f1 100644 (file)
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -220,6 +220,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
        case KVM_CAP_VCPU_ATTRIBUTES:
        case KVM_CAP_PTP_KVM:
        case KVM_CAP_ARM_SYSTEM_SUSPEND:
+       case KVM_CAP_IRQFD_RESAMPLE:
                r = 1;
                break;
        case KVM_CAP_SET_GUEST_DEBUG2:

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 4c5405fc55387028e33e26f83fac20c99a2e5316..d23e25e8432d351dcd33e534f0d1b1765b7317aa 100644 (file)
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -576,6 +576,12 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
                break;
 #endif
 
+#ifdef CONFIG_HAVE_KVM_IRQFD
+       case KVM_CAP_IRQFD_RESAMPLE:
+               r = !xive_enabled();
+               break;
+#endif
+
        case KVM_CAP_PPC_ALLOC_HTAB:
                r = hv_enabled;
                break;

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 39b36562c043f6ba8ad0d29248744fceaaedab63..1eeb9ae57879c8d67c465fffc438e18ed3f05c58 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -573,6 +573,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
        case KVM_CAP_S390_VCPU_RESETS:
        case KVM_CAP_SET_GUEST_DEBUG:
        case KVM_CAP_S390_DIAG318:
+       case KVM_CAP_IRQFD_RESAMPLE:
                r = 1;
                break;
        case KVM_CAP_SET_GUEST_DEBUG2:

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7d6f98b7635fcd2a95c6f4f9355f41e9913f456a..3d852ce8492066705214e84456eb2fc5bda80b42 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4432,6 +4432,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
        case KVM_CAP_VAPIC:
        case KVM_CAP_ENABLE_CAP:
        case KVM_CAP_VM_DISABLE_NX_HUGE_PAGES:
+       case KVM_CAP_IRQFD_RESAMPLE:
                r = 1;
                break;
        case KVM_CAP_EXIT_HYPERCALL:

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d255964ec331ef5c9aebf90243990ef4da0aec2b..b1679d08a216099a379df472a6cc52c268e4e51d 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -4479,7 +4479,6 @@ static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
 #endif
 #ifdef CONFIG_HAVE_KVM_IRQFD
        case KVM_CAP_IRQFD:
-       case KVM_CAP_IRQFD_RESAMPLE:
 #endif
        case KVM_CAP_IOEVENTFD_ANY_LENGTH:
        case KVM_CAP_CHECK_EXTENSION_VM: