diff options
| author | Liran Alon <liran.alon@oracle.com> | 2018-03-12 13:12:47 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2018-03-16 22:01:40 +0100 |
| commit | c4ae60e4bbf8f5fd4929d2c98543d9c163cb336b (patch) | |
| tree | 331db5ddd5008a3ca27dfd069af8b92d731f6358 | |
| parent | dca7f1284f49911b459da313ece5d9c6dc3291f6 (diff) | |
| download | lwn-c4ae60e4bbf8f5fd4929d2c98543d9c163cb336b.tar.gz lwn-c4ae60e4bbf8f5fd4929d2c98543d9c163cb336b.zip | |
KVM: x86: Add module parameter for supporting VMware backdoor
Support access to VMware backdoor requires KVM to intercept #GP
exceptions from guest which introduce slight performance hit.
Therefore, control this support by module parameter.
Note that module parameter is exported as it should be consumed by
kvm_intel & kvm_amd to determine if they should intercept #GP or not.
This commit doesn't change semantics.
It is done as a preparation for future commits.
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 4 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.h | 2 |
3 files changed, 9 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 1d1d53f85ddd..0f5e3c8eaf5d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1887,6 +1887,9 @@ kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs. Default is 0 (don't ignore, but inject #GP) + kvm.enable_vmware_backdoor=[KVM] Support VMware backdoor PV interface. + Default is false (don't support). + kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit KVM MMU at runtime. Default is 0 (off) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 841d9bb2d68c..172f703552ca 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -142,6 +142,10 @@ module_param(lapic_timer_advance_ns, uint, S_IRUGO | S_IWUSR); static bool __read_mostly vector_hashing = true; module_param(vector_hashing, bool, S_IRUGO); +bool __read_mostly enable_vmware_backdoor = false; +module_param(enable_vmware_backdoor, bool, S_IRUGO); +EXPORT_SYMBOL_GPL(enable_vmware_backdoor); + #define KVM_NR_SHARED_MSRS 16 struct kvm_shared_msrs_global { diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index b91215d1fd80..18e2e0a91edc 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -242,6 +242,8 @@ extern unsigned int min_timer_period_us; extern unsigned int lapic_timer_advance_ns; +extern bool enable_vmware_backdoor; + extern struct static_key kvm_no_apic_vcpu; static inline u64 nsec_to_cycles(struct kvm_vcpu *vcpu, u64 nsec) |