diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 2ce6915b70fe..30424fbceb5f 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -29,13 +29,16 @@ bool kvm_mmu_init_tdp_mmu(struct kvm *kvm) return true; } -static __always_inline void kvm_lockdep_assert_mmu_lock_held(struct kvm *kvm, +/* Arbitrarily returns true so that this may be used in if statements. */ +static __always_inline bool kvm_lockdep_assert_mmu_lock_held(struct kvm *kvm, bool shared) { if (shared) lockdep_assert_held_read(&kvm->mmu_lock); else lockdep_assert_held_write(&kvm->mmu_lock); + + return true; } void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm) @@ -172,11 +175,17 @@ static struct kvm_mmu_page *tdp_mmu_next_root(struct kvm *kvm, #define for_each_tdp_mmu_root_yield_safe(_kvm, _root, _as_id, _shared) \ __for_each_tdp_mmu_root_yield_safe(_kvm, _root, _as_id, _shared, false) -#define for_each_tdp_mmu_root(_kvm, _root, _as_id) \ - list_for_each_entry_rcu(_root, &_kvm->arch.tdp_mmu_roots, link, \ - lockdep_is_held_type(&kvm->mmu_lock, 0) || \ - lockdep_is_held(&kvm->arch.tdp_mmu_pages_lock)) \ - if (kvm_mmu_page_as_id(_root) != _as_id) { \ +/* + * Iterate over all TDP MMU roots. Requires that mmu_lock be held for write, + * the implication being that any flow that holds mmu_lock for read is + * inherently yield-friendly and should use the yield-safe variant above. + * Holding mmu_lock for write obviates the need for RCU protection as the list + * is guaranteed to be stable. + */ +#define for_each_tdp_mmu_root(_kvm, _root, _as_id) \ + list_for_each_entry(_root, &_kvm->arch.tdp_mmu_roots, link) \ + if (kvm_lockdep_assert_mmu_lock_held(_kvm, false) && \ + kvm_mmu_page_as_id(_root) != _as_id) { \ } else static struct kvm_mmu_page *tdp_mmu_alloc_sp(struct kvm_vcpu *vcpu)