Merge tag 'v4.19.23' into linux-4.19.y-rt

This is the 4.19.23 stable release

3 files changed, 21 insertions, 19 deletions

diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 3a5f34008d8e..7151b1e756e4 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -66,7 +66,7 @@ static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu);
 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
 static u32 kvm_next_vmid;
 static unsigned int kvm_vmid_bits __read_mostly;
-static DEFINE_RWLOCK(kvm_vmid_lock);
+static DEFINE_SPINLOCK(kvm_vmid_lock);
 
 static bool vgic_present;
 
@@ -482,7 +482,9 @@ void force_vm_exit(const cpumask_t *mask)
  */
 static bool need_new_vmid_gen(struct kvm *kvm)
 {
-	return unlikely(kvm->arch.vmid_gen != atomic64_read(&kvm_vmid_gen));
+	u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen);
+	smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */
+	return unlikely(READ_ONCE(kvm->arch.vmid_gen) != current_vmid_gen);
 }
 
 /**
@@ -497,16 +499,11 @@ static void update_vttbr(struct kvm *kvm)
 {
 	phys_addr_t pgd_phys;
 	u64 vmid;
-	bool new_gen;
 
-	read_lock(&kvm_vmid_lock);
-	new_gen = need_new_vmid_gen(kvm);
-	read_unlock(&kvm_vmid_lock);
-
-	if (!new_gen)
+	if (!need_new_vmid_gen(kvm))
 		return;
 
-	write_lock(&kvm_vmid_lock);
+	spin_lock(&kvm_vmid_lock);
 
 	/*
 	 * We need to re-check the vmid_gen here to ensure that if another vcpu
@@ -514,7 +511,7 @@ static void update_vttbr(struct kvm *kvm)
 	 * use the same vmid.
 	 */
 	if (!need_new_vmid_gen(kvm)) {
-		write_unlock(&kvm_vmid_lock);
+		spin_unlock(&kvm_vmid_lock);
 		return;
 	}
 
@@ -537,7 +534,6 @@ static void update_vttbr(struct kvm *kvm)
 		kvm_call_hyp(__kvm_flush_vm_context);
 	}
 
-	kvm->arch.vmid_gen = atomic64_read(&kvm_vmid_gen);
 	kvm->arch.vmid = kvm_next_vmid;
 	kvm_next_vmid++;
 	kvm_next_vmid &= (1 << kvm_vmid_bits) - 1;
@@ -548,7 +544,10 @@ static void update_vttbr(struct kvm *kvm)
 	vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK(kvm_vmid_bits);
 	kvm->arch.vttbr = kvm_phys_to_vttbr(pgd_phys) | vmid;
 
-	write_unlock(&kvm_vmid_lock);
+	smp_wmb();
+	WRITE_ONCE(kvm->arch.vmid_gen, atomic64_read(&kvm_vmid_gen));
+
+	spin_unlock(&kvm_vmid_lock);
 }
 
 static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
diff --git a/virt/kvm/arm/mmio.c b/virt/kvm/arm/mmio.c
index dac7ceb1a677..08443a15e6be 100644
--- a/virt/kvm/arm/mmio.c
+++ b/virt/kvm/arm/mmio.c
@@ -117,6 +117,12 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		vcpu_set_reg(vcpu, vcpu->arch.mmio_decode.rt, data);
 	}
 
+	/*
+	 * The MMIO instruction is emulated and should not be re-executed
+	 * in the guest.
+	 */
+	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+
 	return 0;
 }
 
@@ -144,11 +150,6 @@ static int decode_hsr(struct kvm_vcpu *vcpu, bool *is_write, int *len)
 	vcpu->arch.mmio_decode.sign_extend = sign_extend;
 	vcpu->arch.mmio_decode.rt = rt;
 
-	/*
-	 * The MMIO instruction is emulated and should not be re-executed
-	 * in the guest.
-	 */
-	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
 	return 0;
 }
 
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f986e31fa68c..0ffb02ff5234 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1959,7 +1959,8 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
 
 int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
-			   void *data, int offset, unsigned long len)
+				  void *data, unsigned int offset,
+				  unsigned long len)
 {
 	struct kvm_memslots *slots = kvm_memslots(kvm);
 	int r;
@@ -2912,8 +2913,10 @@ static int kvm_ioctl_create_device(struct kvm *kvm,
 	if (ops->init)
 		ops->init(dev);
 
+	kvm_get_kvm(kvm);
 	ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
 	if (ret < 0) {
+		kvm_put_kvm(kvm);
 		mutex_lock(&kvm->lock);
 		list_del(&dev->vm_node);
 		mutex_unlock(&kvm->lock);
@@ -2921,7 +2924,6 @@ static int kvm_ioctl_create_device(struct kvm *kvm,
 		return ret;
 	}
 
-	kvm_get_kvm(kvm);
 	cd->fd = ret;
 	return 0;
 }