Commit f9b245e1 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: nVMX: Remove param indirection from nested_vmx_check_msr_switch() 



Passing the enum and doing an indirect lookup is silly when we can
simply pass the field directly.  Remove the "fast path" code in
nested_vmx_check_msr_switch_controls() as it's now nothing more than a
redundant check.

Remove the debug message rather than continue passing the enum for the
address field.  Having debug messages for the MSRs themselves is useful
as MSR legality is a huge space, whereas messing up a physical address
means the VMM is fundamentally broken.

Signed-off-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 461b4ba4

arch/x86/kvm/vmx/nested.c

+10 −24
Original line number Diff line number Diff line
@@ -700,45 +700,31 @@ static int nested_vmx_check_apicv_controls(struct kvm_vcpu *vcpu, 
}



static int nested_vmx_check_msr_switch(struct kvm_vcpu *vcpu,

				       unsigned long count_field,

				       unsigned long addr_field)

				       u32 count, u64 addr)

{

	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);

	int maxphyaddr;

	u64 count, addr;



	if (vmcs12_read_any(vmcs12, count_field, &count) ||

	    vmcs12_read_any(vmcs12, addr_field, &addr)) {

		WARN_ON(1);

		return -EINVAL;

	}

	if (count == 0)

		return 0;

	maxphyaddr = cpuid_maxphyaddr(vcpu);

	if (!IS_ALIGNED(addr, 16) || addr >> maxphyaddr ||

	    (addr + count * sizeof(struct vmx_msr_entry) - 1) >> maxphyaddr) {

		pr_debug_ratelimited(

			"nVMX: invalid MSR switch (0x%lx, %d, %llu, 0x%08llx)",

			addr_field, maxphyaddr, count, addr);

	    (addr + count * sizeof(struct vmx_msr_entry) - 1) >> maxphyaddr)

		return -EINVAL;

	}



	return 0;

}



static int nested_vmx_check_msr_switch_controls(struct kvm_vcpu *vcpu,

						struct vmcs12 *vmcs12)

{

	if (vmcs12->vm_exit_msr_load_count == 0 &&

	    vmcs12->vm_exit_msr_store_count == 0 &&

	    vmcs12->vm_entry_msr_load_count == 0)

		return 0; /* Fast path */

	if (nested_vmx_check_msr_switch(vcpu, VM_EXIT_MSR_LOAD_COUNT,

					VM_EXIT_MSR_LOAD_ADDR) ||

	    nested_vmx_check_msr_switch(vcpu, VM_EXIT_MSR_STORE_COUNT,

					VM_EXIT_MSR_STORE_ADDR) ||

	    nested_vmx_check_msr_switch(vcpu, VM_ENTRY_MSR_LOAD_COUNT,

					VM_ENTRY_MSR_LOAD_ADDR))

	if (nested_vmx_check_msr_switch(vcpu, vmcs12->vm_exit_msr_load_count,

					vmcs12->vm_exit_msr_load_addr) ||

	    nested_vmx_check_msr_switch(vcpu, vmcs12->vm_exit_msr_store_count,

					vmcs12->vm_exit_msr_store_addr) ||

	    nested_vmx_check_msr_switch(vcpu, vmcs12->vm_entry_msr_load_count,

					vmcs12->vm_entry_msr_load_addr))

		return -EINVAL;



	return 0;

}

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