On 02/02/21 19:57, Ben Gardon wrote:
@@ -1485,7 +1489,9 @@ void kvm_tdp_mmu_zap_collapsible_sptes(struct kvm *kvm,
struct kvm_mmu_page *root;
int root_as_id;
- for_each_tdp_mmu_root_yield_safe(kvm, root, false) {
+ read_lock(&kvm->mmu_lock);
+
+ for_each_tdp_mmu_root_yield_safe(kvm, root, true) {
root_as_id = kvm_mmu_page_as_id(root);
if (root_as_id != slot->as_id)
continue;
@@ -1493,6 +1499,8 @@ void kvm_tdp_mmu_zap_collapsible_sptes(struct kvm *kvm,
zap_collapsible_spte_range(kvm, root, slot->base_gfn,
slot->base_gfn + slot->npages);
}
+
+ read_unlock(&kvm->mmu_lock);
}
I'd prefer the functions to be consistent about who takes the lock,
either mmu.c or tdp_mmu.c. Since everywhere else you're doing it in
mmu.c, that would be:
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 0554d9c5c5d4..386ee4b703d9 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5567,10 +5567,13 @@ void kvm_mmu_zap_collapsible_sptes(struct kvm *kvm,
write_lock(&kvm->mmu_lock);
slot_handle_leaf(kvm, (struct kvm_memory_slot *)memslot,
kvm_mmu_zap_collapsible_spte, true);
+ write_unlock(&kvm->mmu_lock);
- if (kvm->arch.tdp_mmu_enabled)
+ if (kvm->arch.tdp_mmu_enabled) {
+ read_lock(&kvm->mmu_lock);
kvm_tdp_mmu_zap_collapsible_sptes(kvm, memslot);
- write_unlock(&kvm->mmu_lock);
+ read_unlock(&kvm->mmu_lock);
+ }
}
void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
and just lockdep_assert_held_read here.
- tdp_mmu_set_spte(kvm, &iter, 0);
-
- spte_set = true;
Is it correct to remove this assignment?
Paolo
