Since Linux commit 00f918f61c56 ("RISC-V: KVM: Skeletal in-kernel AIA irqchip support") checking KVM_CAP_IRQCHIP returns non-zero when the RISC-V platform has AIA. The cap indicates KVM supports at least one of the following ioctls: KVM_CREATE_IRQCHIP KVM_IRQ_LINE KVM_GET_IRQCHIP KVM_SET_IRQCHIP KVM_GET_LAPIC KVM_SET_LAPIC but the cap doesn't imply that KVM must support any of those ioctls in particular. However, QEMU was assuming the KVM_CREATE_IRQCHIP ioctl was supported. Stop making that assumption by introducing a KVM parameter that each architecture which supports KVM_CREATE_IRQCHIP sets. Adding parameters isn't awesome, but given how the KVM_CAP_IRQCHIP isn't very helpful on its own, we don't have a lot of options. Signed-off-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx> --- While this fixes booting guests on riscv KVM with AIA it's unlikely to get merged before the QEMU support for KVM AIA[1] lands, which would also fix the issue. I think this patch is still worth considering though since QEMU's assumption is wrong. [1] https://lore.kernel.org/all/20230714084429.22349-1-yongxuan.wang@xxxxxxxxxx/ accel/kvm/kvm-all.c | 5 ++++- include/sysemu/kvm.h | 1 + target/arm/kvm.c | 3 +++ target/i386/kvm/kvm.c | 2 ++ target/s390x/kvm/kvm.c | 3 +++ 5 files changed, 13 insertions(+), 1 deletion(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 373d876c0580..0f5ff8630502 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -86,6 +86,7 @@ struct KVMParkedVcpu { }; KVMState *kvm_state; +bool kvm_has_create_irqchip; bool kvm_kernel_irqchip; bool kvm_split_irqchip; bool kvm_async_interrupts_allowed; @@ -2377,8 +2378,10 @@ static void kvm_irqchip_create(KVMState *s) if (s->kernel_irqchip_split == ON_OFF_AUTO_ON) { error_report("Split IRQ chip mode not supported."); exit(1); - } else { + } else if (kvm_has_create_irqchip) { ret = kvm_vm_ioctl(s, KVM_CREATE_IRQCHIP); + } else { + return; } } if (ret < 0) { diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index 115f0cca79d1..84b1bb3dc91e 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -32,6 +32,7 @@ #ifdef CONFIG_KVM_IS_POSSIBLE extern bool kvm_allowed; +extern bool kvm_has_create_irqchip; extern bool kvm_kernel_irqchip; extern bool kvm_split_irqchip; extern bool kvm_async_interrupts_allowed; diff --git a/target/arm/kvm.c b/target/arm/kvm.c index b4c7654f4980..2fa87b495d68 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -250,6 +250,9 @@ int kvm_arm_get_max_vm_ipa_size(MachineState *ms, bool *fixed_ipa) int kvm_arch_init(MachineState *ms, KVMState *s) { int ret = 0; + + kvm_has_create_irqchip = kvm_check_extension(s, KVM_CAP_IRQCHIP); + /* For ARM interrupt delivery is always asynchronous, * whether we are using an in-kernel VGIC or not. */ diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index ebfaf3d24c79..6363e67f092d 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -2771,6 +2771,8 @@ int kvm_arch_init(MachineState *ms, KVMState *s) } } + kvm_has_create_irqchip = kvm_check_extension(s, KVM_CAP_IRQCHIP); + return 0; } diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c index a9e5880349d9..c053304adf94 100644 --- a/target/s390x/kvm/kvm.c +++ b/target/s390x/kvm/kvm.c @@ -391,6 +391,9 @@ int kvm_arch_init(MachineState *ms, KVMState *s) } kvm_set_max_memslot_size(KVM_SLOT_MAX_BYTES); + + kvm_has_create_irqchip = kvm_check_extension(s, KVM_CAP_S390_IRQCHIP); + return 0; } -- 2.41.0