diff options
| -rw-r--r-- | Documentation/virt/kvm/api.rst | 50 | ||||
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 7 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 8 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 1 |
4 files changed, 66 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 55efa82e37eb..07a45474abe9 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -7083,6 +7083,56 @@ resource that is controlled with the H_SET_MODE hypercall. This capability allows a guest kernel to use a better-performance mode for handling interrupts and system calls. +7.31 KVM_CAP_DISABLE_QUIRKS2 +---------------------------- + +:Capability: KVM_CAP_DISABLE_QUIRKS2 +:Parameters: args[0] - set of KVM quirks to disable +:Architectures: x86 +:Type: vm + +This capability, if enabled, will cause KVM to disable some behavior +quirks. + +Calling KVM_CHECK_EXTENSION for this capability returns a bitmask of +quirks that can be disabled in KVM. + +The argument to KVM_ENABLE_CAP for this capability is a bitmask of +quirks to disable, and must be a subset of the bitmask returned by +KVM_CHECK_EXTENSION. + +The valid bits in cap.args[0] are: + +=================================== ============================================ + KVM_X86_QUIRK_LINT0_REENABLED By default, the reset value for the LVT + LINT0 register is 0x700 (APIC_MODE_EXTINT). + When this quirk is disabled, the reset value + is 0x10000 (APIC_LVT_MASKED). + + KVM_X86_QUIRK_CD_NW_CLEARED By default, KVM clears CR0.CD and CR0.NW. + When this quirk is disabled, KVM does not + change the value of CR0.CD and CR0.NW. + + KVM_X86_QUIRK_LAPIC_MMIO_HOLE By default, the MMIO LAPIC interface is + available even when configured for x2APIC + mode. When this quirk is disabled, KVM + disables the MMIO LAPIC interface if the + LAPIC is in x2APIC mode. + + KVM_X86_QUIRK_OUT_7E_INC_RIP By default, KVM pre-increments %rip before + exiting to userspace for an OUT instruction + to port 0x7e. When this quirk is disabled, + KVM does not pre-increment %rip before + exiting to userspace. + + KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT When this quirk is disabled, KVM sets + CPUID.01H:ECX[bit 3] (MONITOR/MWAIT) if + IA32_MISC_ENABLE[bit 18] (MWAIT) is set. + Additionally, when this quirk is disabled, + KVM clears CPUID.01H:ECX[bit 3] if + IA32_MISC_ENABLE[bit 18] is cleared. +=================================== ============================================ + 8. Other capabilities. ====================== diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 3a2c855f04e3..0ddc2e67a731 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1966,4 +1966,11 @@ int memslot_rmap_alloc(struct kvm_memory_slot *slot, unsigned long npages); #define KVM_CLOCK_VALID_FLAGS \ (KVM_CLOCK_TSC_STABLE | KVM_CLOCK_REALTIME | KVM_CLOCK_HOST_TSC) +#define KVM_X86_VALID_QUIRKS \ + (KVM_X86_QUIRK_LINT0_REENABLED | \ + KVM_X86_QUIRK_CD_NW_CLEARED | \ + KVM_X86_QUIRK_LAPIC_MMIO_HOLE | \ + KVM_X86_QUIRK_OUT_7E_INC_RIP | \ + KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT) + #endif /* _ASM_X86_KVM_HOST_H */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c58265d9f1b2..fe2171b11441 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4363,6 +4363,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = enable_pmu ? KVM_CAP_PMU_VALID_MASK : 0; break; } + case KVM_CAP_DISABLE_QUIRKS2: + r = KVM_X86_VALID_QUIRKS; + break; default: break; } @@ -5909,6 +5912,11 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm, return -EINVAL; switch (cap->cap) { + case KVM_CAP_DISABLE_QUIRKS2: + r = -EINVAL; + if (cap->args[0] & ~KVM_X86_VALID_QUIRKS) + break; + fallthrough; case KVM_CAP_DISABLE_QUIRKS: kvm->arch.disabled_quirks = cap->args[0]; r = 0; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index d2f1efc3aa35..91a6fe4e02c0 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1143,6 +1143,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_PPC_AIL_MODE_3 210 #define KVM_CAP_S390_MEM_OP_EXTENSION 211 #define KVM_CAP_PMU_CAPABILITY 212 +#define KVM_CAP_DISABLE_QUIRKS2 213 #ifdef KVM_CAP_IRQ_ROUTING |