From 0c8eb2884a42d992c7726539328b7d3568f22143 Mon Sep 17 00:00:00 2001
From: Andreas Gruenbacher <agruenba@redhat.com>
Date: Mon, 2 Aug 2021 13:46:19 +0200
Subject: [PATCH] powerpc/kvm: Fix kvm_use_magic_page
References: bsc#1156395
Patch-mainline: v5.16-rc1
Git-commit: 0c8eb2884a42d992c7726539328b7d3568f22143
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>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/kernel/kvm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/kvm.c b/arch/powerpc/kernel/kvm.c
index 617eba82531c..d89cf802d9aa 100644
--- a/arch/powerpc/kernel/kvm.c
+++ b/arch/powerpc/kernel/kvm.c
@@ -669,7 +669,7 @@ static void __init 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;
}
--
2.35.3