From ea1c63bab1b44d88bb3e48dbf6a5f5a947beada5 Mon Sep 17 00:00:00 2001 From: Quentin Perret Date: Tue, 5 Oct 2021 10:01:42 +0100 Subject: [PATCH] UPSTREAM: KVM: arm64: Report corrupted refcount at EL2 Some of the refcount manipulation helpers used at EL2 are instrumented to catch a corrupted state, but not all of them are treated equally. Let's make things more consistent by instrumenting hyp_page_ref_dec_and_test() as well. Acked-by: Will Deacon Suggested-by: Will Deacon Signed-off-by: Quentin Perret Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20211005090155.734578-6-qperret@google.com (cherry picked from commit 7615c2a514788559c6684234b8fc27f3a843c2c6) Signed-off-by: Will Deacon Bug: 198418208 Change-Id: I68831927545cd1050900096be319f5b0dcb96576 --- arch/arm64/kvm/hyp/nvhe/page_alloc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/kvm/hyp/nvhe/page_alloc.c b/arch/arm64/kvm/hyp/nvhe/page_alloc.c index a6e874e61a40..0bd7701ad1df 100644 --- a/arch/arm64/kvm/hyp/nvhe/page_alloc.c +++ b/arch/arm64/kvm/hyp/nvhe/page_alloc.c @@ -152,6 +152,7 @@ static inline void hyp_page_ref_inc(struct hyp_page *p) static inline int hyp_page_ref_dec_and_test(struct hyp_page *p) { + BUG_ON(!p->refcount); p->refcount--; return (p->refcount == 0); }