Commit 38081d28 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: selftests: Trust that MAXPHYADDR > memslot0 in vmx_apic_access_test 



Use vm->max_gfn to compute the highest gpa in vmx_apic_access_test, and
blindly trust that the highest gfn/gpa will be well above the memory
carved out for memslot0.  The existing check is beyond paranoid; KVM
doesn't support CPUs with host.MAXPHYADDR < 32, and the selftests are all
kinds of hosed if memslot0 overlaps the local xAPIC, which resides above
"lower" (below 4gb) DRAM.

Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 6e1d13bf

tools/testing/selftests/kvm/x86_64/vmx_apic_access_test.c

+1 −8
Original line number Diff line number Diff line
@@ -72,8 +72,6 @@ static void l1_guest_code(struct vmx_pages *vmx_pages, unsigned long high_gpa) 
int main(int argc, char *argv[])

{

	unsigned long apic_access_addr = ~0ul;

	unsigned int paddr_width;

	unsigned int vaddr_width;

	vm_vaddr_t vmx_pages_gva;

	unsigned long high_gpa;

	struct vmx_pages *vmx;
@@ -86,12 +84,7 @@ int main(int argc, char *argv[]) 


	vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code);



	kvm_get_cpu_address_width(&paddr_width, &vaddr_width);

	high_gpa = (1ul << paddr_width) - getpagesize();

	if ((unsigned long)DEFAULT_GUEST_PHY_PAGES * getpagesize() > high_gpa) {

		print_skip("No unbacked physical page available");

		exit(KSFT_SKIP);

	}

	high_gpa = (vm->max_gfn - 1) << vm->page_shift;



	vmx = vcpu_alloc_vmx(vm, &vmx_pages_gva);

	prepare_virtualize_apic_accesses(vmx, vm);