From: Sean Christopherson <seanjc@xxxxxxxxxx>
Play nice with a NULL @old or @new when handling memslot updates so that
common KVM can pass NULL for one or the other in CREATE and DELETE cases
instead of having to synthesize a dummy memslot.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@xxxxxxxxxx>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@xxxxxxxxxx>
---
arch/x86/kvm/x86.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1a598b0c3e36..f25d224d21d9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -11758,13 +11758,15 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
const struct kvm_memory_slot *new,
enum kvm_mr_change change)
{
- bool log_dirty_pages = new->flags & KVM_MEM_LOG_DIRTY_PAGES;
+ u32 old_flags = old ? old->flags : 0;
+ u32 new_flags = new ? new->flags : 0;
+ bool log_dirty_pages = new_flags & KVM_MEM_LOG_DIRTY_PAGES;
/*
* Update CPU dirty logging if dirty logging is being toggled. This
* applies to all operations.
*/
- if ((old->flags ^ new->flags) & KVM_MEM_LOG_DIRTY_PAGES)
+ if ((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES)
kvm_mmu_update_cpu_dirty_logging(kvm, log_dirty_pages);
/*
@@ -11782,7 +11784,7 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
* MOVE/DELETE: The old mappings will already have been cleaned up by
* kvm_arch_flush_shadow_memslot().
*/
- if ((change != KVM_MR_FLAGS_ONLY) || (new->flags & KVM_MEM_READONLY))
+ if ((change != KVM_MR_FLAGS_ONLY) || (new_flags & KVM_MEM_READONLY))
return;
/*
@@ -11790,7 +11792,7 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
* other flag is LOG_DIRTY_PAGES, i.e. something is wrong if dirty
* logging isn't being toggled on or off.
*/
- if (WARN_ON_ONCE(!((old->flags ^ new->flags) & KVM_MEM_LOG_DIRTY_PAGES)))
+ if (WARN_ON_ONCE(!((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES)))
return;
if (!log_dirty_pages) {
