diff mbox series

[v5,06/13] KVM: Move WARN on invalid memslot index to update_memslots()

Message ID f01919799c5cac1f6cf90c7d1f3fc17b389a3bee.1632171479.git.maciej.szmigiero@oracle.com (mailing list archive)
State New, archived
Headers show
Series KVM: Scalable memslots implementation | expand

Commit Message

Maciej S. Szmigiero Sept. 20, 2021, 9:38 p.m. UTC 
From: "Maciej S. Szmigiero" <maciej.szmigiero@oracle.com>

Since kvm_memslot_move_forward() can theoretically return a negative
memslot index even when kvm_memslot_move_backward() returned a positive one
(and so did not WARN) let's just move the warning to the common code.

Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
---
 virt/kvm/kvm_main.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

Comments

Sean Christopherson Oct. 19, 2021, 11:42 p.m. UTC | #1 
On Mon, Sep 20, 2021, Maciej S. Szmigiero wrote:
> From: "Maciej S. Szmigiero" <maciej.szmigiero@oracle.com>
> 
> Since kvm_memslot_move_forward() can theoretically return a negative
> memslot index even when kvm_memslot_move_backward() returned a positive one
> (and so did not WARN) let's just move the warning to the common code.
> 
> Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> ---

Reviewed-by: Sean Christopherson <seanjc@google.com>
diff mbox series

Patch

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 14043a6edb88..348fae880189 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1281,8 +1281,7 @@  static inline int kvm_memslot_move_backward(struct kvm_memslots *slots,
 	struct kvm_memory_slot *mslots = slots->memslots;
 	int i;
 
-	if (WARN_ON_ONCE(slots->id_to_index[memslot->id] == -1) ||
-	    WARN_ON_ONCE(!slots->used_slots))
+	if (slots->id_to_index[memslot->id] == -1 || !slots->used_slots)
 		return -1;
 
 	/*
@@ -1386,6 +1385,9 @@  static void update_memslots(struct kvm_memslots *slots,
 			i = kvm_memslot_move_backward(slots, memslot);
 		i = kvm_memslot_move_forward(slots, memslot, i);
 
+		if (WARN_ON_ONCE(i < 0))
+			return;
+
 		/*
 		 * Copy the memslot to its new position in memslots and update
 		 * its index accordingly.