Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c4ae60e4 authored by Liran Alon's avatar Liran Alon Committed by Paolo Bonzini
Browse files

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: default avatarLiran Alon <liran.alon@oracle.com>
Reviewed-by: default avatarNikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: default avatarRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent dca7f128

Documentation/admin-guide/kernel-parameters.txt

+3 −0
Original line number Diff line number Diff line
@@ -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)

arch/x86/kvm/x86.c

+4 −0
Original line number Diff line number Diff line
@@ -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 {

arch/x86/kvm/x86.h

+2 −0
Original line number Diff line number Diff line
@@ -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)