From: Andreas Gruenbacher agruenba@redhat.com
commit 0c8eb2884a42d992c7726539328b7d3568f22143 upstream.
When switching from __get_user to fault_in_pages_readable, commit 9f9eae5ce717 broke kvm_use_magic_page: like __get_user, fault_in_pages_readable returns 0 on success.
Fixes: 9f9eae5ce717 ("powerpc/kvm: Prefer fault_in_pages_readable function") Cc: stable@vger.kernel.org # v4.18+ Signed-off-by: Andreas Gruenbacher agruenba@redhat.com Signed-off-by: Anand Jain anand.jain@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/powerpc/kernel/kvm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/powerpc/kernel/kvm.c +++ b/arch/powerpc/kernel/kvm.c @@ -680,7 +680,7 @@ static void kvm_use_magic_page(void) on_each_cpu(kvm_map_magic_page, &features, 1);
/* Quick self-test to see if the mapping works */ - if (!fault_in_pages_readable((const char *)KVM_MAGIC_PAGE, sizeof(u32))) { + if (fault_in_pages_readable((const char *)KVM_MAGIC_PAGE, sizeof(u32))) { kvm_patching_worked = false; return; }