From 069f30c619792d5202d72fecd842cacbee260561 Mon Sep 17 00:00:00 2001 From: Mingwei Zhang Date: Fri, 28 Jul 2023 17:47:21 -0700 Subject: [PATCH] KVM: x86/mmu: Plumb "struct kvm" all the way to pte_list_remove() Plumb "struct kvm" all the way to pte_list_remove() to allow the usage of KVM_BUG() and/or KVM_BUG_ON(). This will allow killing only the offending VM instead of doing BUG() if the kernel is built with CONFIG_BUG_ON_DATA_CORRUPTION=n, i.e. does NOT want to BUG() if KVM's data structures (rmaps) appear to be corrupted. Signed-off-by: Mingwei Zhang [sean: tweak changelog] Link: https://lore.kernel.org/r/20230729004722.1056172-12-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu/mmu.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index baa3123..f518dd5 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -961,7 +961,8 @@ static int pte_list_add(struct kvm_mmu_memory_cache *cache, u64 *spte, return count; } -static void pte_list_desc_remove_entry(struct kvm_rmap_head *rmap_head, +static void pte_list_desc_remove_entry(struct kvm *kvm, + struct kvm_rmap_head *rmap_head, struct pte_list_desc *desc, int i) { struct pte_list_desc *head_desc = (struct pte_list_desc *)(rmap_head->val & ~1ul); @@ -997,7 +998,8 @@ static void pte_list_desc_remove_entry(struct kvm_rmap_head *rmap_head, mmu_free_pte_list_desc(head_desc); } -static void pte_list_remove(u64 *spte, struct kvm_rmap_head *rmap_head) +static void pte_list_remove(struct kvm *kvm, u64 *spte, + struct kvm_rmap_head *rmap_head) { struct pte_list_desc *desc; int i; @@ -1016,7 +1018,8 @@ static void pte_list_remove(u64 *spte, struct kvm_rmap_head *rmap_head) while (desc) { for (i = 0; i < desc->spte_count; ++i) { if (desc->sptes[i] == spte) { - pte_list_desc_remove_entry(rmap_head, desc, i); + pte_list_desc_remove_entry(kvm, rmap_head, + desc, i); return; } } @@ -1031,7 +1034,7 @@ static void kvm_zap_one_rmap_spte(struct kvm *kvm, struct kvm_rmap_head *rmap_head, u64 *sptep) { mmu_spte_clear_track_bits(kvm, sptep); - pte_list_remove(sptep, rmap_head); + pte_list_remove(kvm, sptep, rmap_head); } /* Return true if at least one SPTE was zapped, false otherwise */ @@ -1106,7 +1109,7 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) slot = __gfn_to_memslot(slots, gfn); rmap_head = gfn_to_rmap(gfn, sp->role.level, slot); - pte_list_remove(spte, rmap_head); + pte_list_remove(kvm, spte, rmap_head); } /* @@ -1753,16 +1756,16 @@ static void mmu_page_add_parent_pte(struct kvm_mmu_memory_cache *cache, pte_list_add(cache, parent_pte, &sp->parent_ptes); } -static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp, +static void mmu_page_remove_parent_pte(struct kvm *kvm, struct kvm_mmu_page *sp, u64 *parent_pte) { - pte_list_remove(parent_pte, &sp->parent_ptes); + pte_list_remove(kvm, parent_pte, &sp->parent_ptes); } -static void drop_parent_pte(struct kvm_mmu_page *sp, +static void drop_parent_pte(struct kvm *kvm, struct kvm_mmu_page *sp, u64 *parent_pte) { - mmu_page_remove_parent_pte(sp, parent_pte); + mmu_page_remove_parent_pte(kvm, sp, parent_pte); mmu_spte_clear_no_track(parent_pte); } @@ -2477,7 +2480,7 @@ static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep, if (child->role.access == direct_access) return; - drop_parent_pte(child, sptep); + drop_parent_pte(vcpu->kvm, child, sptep); kvm_flush_remote_tlbs_sptep(vcpu->kvm, sptep); } } @@ -2495,7 +2498,7 @@ static int mmu_page_zap_pte(struct kvm *kvm, struct kvm_mmu_page *sp, drop_spte(kvm, spte); } else { child = spte_to_child_sp(pte); - drop_parent_pte(child, spte); + drop_parent_pte(kvm, child, spte); /* * Recursively zap nested TDP SPs, parentless SPs are @@ -2526,13 +2529,13 @@ static int kvm_mmu_page_unlink_children(struct kvm *kvm, return zapped; } -static void kvm_mmu_unlink_parents(struct kvm_mmu_page *sp) +static void kvm_mmu_unlink_parents(struct kvm *kvm, struct kvm_mmu_page *sp) { u64 *sptep; struct rmap_iterator iter; while ((sptep = rmap_get_first(&sp->parent_ptes, &iter))) - drop_parent_pte(sp, sptep); + drop_parent_pte(kvm, sp, sptep); } static int mmu_zap_unsync_children(struct kvm *kvm, @@ -2571,7 +2574,7 @@ static bool __kvm_mmu_prepare_zap_page(struct kvm *kvm, ++kvm->stat.mmu_shadow_zapped; *nr_zapped = mmu_zap_unsync_children(kvm, sp, invalid_list); *nr_zapped += kvm_mmu_page_unlink_children(kvm, sp, invalid_list); - kvm_mmu_unlink_parents(sp); + kvm_mmu_unlink_parents(kvm, sp); /* Zapping children means active_mmu_pages has become unstable. */ list_unstable = *nr_zapped; @@ -2929,7 +2932,7 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot, u64 pte = *sptep; child = spte_to_child_sp(pte); - drop_parent_pte(child, sptep); + drop_parent_pte(vcpu->kvm, child, sptep); flush = true; } else if (pfn != spte_to_pfn(*sptep)) { drop_spte(vcpu->kvm, sptep); -- 2.7.4