5.4-stable patches

added patches:
	kvm-x86-mmu-remove-the-defunct-update_pte-paging-hook.patch

diff --git a/queue-5.4/kvm-x86-mmu-remove-the-defunct-update_pte-paging-hook.patch b/queue-5.4/kvm-x86-mmu-remove-the-defunct-update_pte-paging-hook.patch
new file mode 100644 (file)
index 0000000..20ab9f8
--- /dev/null
+++ b/queue-5.4/kvm-x86-mmu-remove-the-defunct-update_pte-paging-hook.patch
@@ -0,0 +1,158 @@
+From c5e2184d1544f9e56140791eff1a351bea2e63b9 Mon Sep 17 00:00:00 2001
+From: Sean Christopherson <seanjc@google.com>
+Date: Thu, 14 Jan 2021 16:40:51 -0800
+Subject: KVM: x86/mmu: Remove the defunct update_pte() paging hook
+
+From: Sean Christopherson <seanjc@google.com>
+
+commit c5e2184d1544f9e56140791eff1a351bea2e63b9 upstream.
+
+Remove the update_pte() shadow paging logic, which was obsoleted by
+commit 4731d4c7a077 ("KVM: MMU: out of sync shadow core"), but never
+removed.  As pointed out by Yu, KVM never write protects leaf page
+tables for the purposes of shadow paging, and instead marks their
+associated shadow page as unsync so that the guest can write PTEs at
+will.
+
+The update_pte() path, which predates the unsync logic, optimizes COW
+scenarios by refreshing leaf SPTEs when they are written, as opposed to
+zapping the SPTE, restarting the guest, and installing the new SPTE on
+the subsequent fault.  Since KVM no longer write-protects leaf page
+tables, update_pte() is unreachable and can be dropped.
+
+Reported-by: Yu Zhang <yu.c.zhang@intel.com>
+Signed-off-by: Sean Christopherson <seanjc@google.com>
+Message-Id: <20210115004051.4099250-1-seanjc@google.com>
+Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
+(jwang: backport to 5.4 to fix a warning on AMD nested Virtualization)
+Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/x86/include/asm/kvm_host.h |    3 ---
+ arch/x86/kvm/mmu.c              |   33 ++-------------------------------
+ arch/x86/kvm/x86.c              |    1 -
+ 3 files changed, 2 insertions(+), 35 deletions(-)
+
+--- a/arch/x86/include/asm/kvm_host.h
++++ b/arch/x86/include/asm/kvm_host.h
+@@ -391,8 +391,6 @@ struct kvm_mmu {
+       int (*sync_page)(struct kvm_vcpu *vcpu,
+                        struct kvm_mmu_page *sp);
+       void (*invlpg)(struct kvm_vcpu *vcpu, gva_t gva, hpa_t root_hpa);
+-      void (*update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
+-                         u64 *spte, const void *pte);
+       hpa_t root_hpa;
+       gpa_t root_cr3;
+       union kvm_mmu_role mmu_role;
+@@ -944,7 +942,6 @@ struct kvm_arch {
+ struct kvm_vm_stat {
+       ulong mmu_shadow_zapped;
+       ulong mmu_pte_write;
+-      ulong mmu_pte_updated;
+       ulong mmu_pde_zapped;
+       ulong mmu_flooded;
+       ulong mmu_recycled;
+--- a/arch/x86/kvm/mmu.c
++++ b/arch/x86/kvm/mmu.c
+@@ -2243,13 +2243,6 @@ static void nonpaging_invlpg(struct kvm_
+ {
+ }
+ 
+-static void nonpaging_update_pte(struct kvm_vcpu *vcpu,
+-                               struct kvm_mmu_page *sp, u64 *spte,
+-                               const void *pte)
+-{
+-      WARN_ON(1);
+-}
+-
+ #define KVM_PAGE_ARRAY_NR 16
+ 
+ struct kvm_mmu_pages {
+@@ -4356,7 +4349,6 @@ static void nonpaging_init_context(struc
+       context->gva_to_gpa = nonpaging_gva_to_gpa;
+       context->sync_page = nonpaging_sync_page;
+       context->invlpg = nonpaging_invlpg;
+-      context->update_pte = nonpaging_update_pte;
+       context->root_level = 0;
+       context->shadow_root_level = PT32E_ROOT_LEVEL;
+       context->direct_map = true;
+@@ -4935,7 +4927,6 @@ static void paging64_init_context_common
+       context->gva_to_gpa = paging64_gva_to_gpa;
+       context->sync_page = paging64_sync_page;
+       context->invlpg = paging64_invlpg;
+-      context->update_pte = paging64_update_pte;
+       context->shadow_root_level = level;
+       context->direct_map = false;
+ }
+@@ -4964,7 +4955,6 @@ static void paging32_init_context(struct
+       context->gva_to_gpa = paging32_gva_to_gpa;
+       context->sync_page = paging32_sync_page;
+       context->invlpg = paging32_invlpg;
+-      context->update_pte = paging32_update_pte;
+       context->shadow_root_level = PT32E_ROOT_LEVEL;
+       context->direct_map = false;
+ }
+@@ -5039,7 +5029,6 @@ static void init_kvm_tdp_mmu(struct kvm_
+       context->page_fault = tdp_page_fault;
+       context->sync_page = nonpaging_sync_page;
+       context->invlpg = nonpaging_invlpg;
+-      context->update_pte = nonpaging_update_pte;
+       context->shadow_root_level = kvm_x86_ops->get_tdp_level(vcpu);
+       context->direct_map = true;
+       context->set_cr3 = kvm_x86_ops->set_tdp_cr3;
+@@ -5172,7 +5161,6 @@ void kvm_init_shadow_ept_mmu(struct kvm_
+       context->gva_to_gpa = ept_gva_to_gpa;
+       context->sync_page = ept_sync_page;
+       context->invlpg = ept_invlpg;
+-      context->update_pte = ept_update_pte;
+       context->root_level = PT64_ROOT_4LEVEL;
+       context->direct_map = false;
+       context->mmu_role.as_u64 = new_role.as_u64;
+@@ -5312,19 +5300,6 @@ void kvm_mmu_unload(struct kvm_vcpu *vcp
+ }
+ EXPORT_SYMBOL_GPL(kvm_mmu_unload);
+ 
+-static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
+-                                struct kvm_mmu_page *sp, u64 *spte,
+-                                const void *new)
+-{
+-      if (sp->role.level != PT_PAGE_TABLE_LEVEL) {
+-              ++vcpu->kvm->stat.mmu_pde_zapped;
+-              return;
+-        }
+-
+-      ++vcpu->kvm->stat.mmu_pte_updated;
+-      vcpu->arch.mmu->update_pte(vcpu, sp, spte, new);
+-}
+-
+ static bool need_remote_flush(u64 old, u64 new)
+ {
+       if (!is_shadow_present_pte(old))
+@@ -5490,14 +5465,10 @@ static void kvm_mmu_pte_write(struct kvm
+ 
+               local_flush = true;
+               while (npte--) {
+-                      u32 base_role = vcpu->arch.mmu->mmu_role.base.word;
+-
+                       entry = *spte;
+                       mmu_page_zap_pte(vcpu->kvm, sp, spte);
+-                      if (gentry &&
+-                            !((sp->role.word ^ base_role)
+-                            & mmu_base_role_mask.word) && rmap_can_add(vcpu))
+-                              mmu_pte_write_new_pte(vcpu, sp, spte, &gentry);
++                      if (gentry && sp->role.level != PG_LEVEL_4K)
++                              ++vcpu->kvm->stat.mmu_pde_zapped;
+                       if (need_remote_flush(entry, *spte))
+                               remote_flush = true;
+                       ++spte;
+--- a/arch/x86/kvm/x86.c
++++ b/arch/x86/kvm/x86.c
+@@ -208,7 +208,6 @@ struct kvm_stats_debugfs_item debugfs_en
+       { "l1d_flush", VCPU_STAT(l1d_flush) },
+       { "mmu_shadow_zapped", VM_STAT(mmu_shadow_zapped) },
+       { "mmu_pte_write", VM_STAT(mmu_pte_write) },
+-      { "mmu_pte_updated", VM_STAT(mmu_pte_updated) },
+       { "mmu_pde_zapped", VM_STAT(mmu_pde_zapped) },
+       { "mmu_flooded", VM_STAT(mmu_flooded) },
+       { "mmu_recycled", VM_STAT(mmu_recycled) },

diff --git a/queue-5.4/series b/queue-5.4/series
index 39e981e9356ab7e62c1b86e520c60772a4778004..788a53d053d7835eba4dd031d9a72aec4af2d399 100644 (file)
--- a/queue-5.4/series
+++ b/queue-5.4/series
@@ -1,3 +1,4 @@
 tpm-fix-error-return-code-in-tpm2_get_cc_attrs_tbl.patch
 tpm-tpm_tis-extend-locality-handling-to-tpm2-in-tpm_tis_gen_interrupt.patch
 tpm-tpm_tis-reserve-locality-in-tpm_tis_resume.patch
+kvm-x86-mmu-remove-the-defunct-update_pte-paging-hook.patch