[PATCH 5.10 528/545] KVM: Add infrastructure and macro to mark VM as bugged

From: Greg Kroah-Hartman
Date: Fri Aug 19 2022 - 12:53:37 EST


From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>

commit 0b8f11737cffc1a406d1134b58687abc29d76b52 upstream

Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
Reviewed-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Message-Id: <3a0998645c328bf0895f1290e61821b70f048549.1625186503.git.isaku.yamahata@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
[SG: Adjusted context for kernel version 5.10]
Signed-off-by: Stefan Ghinea <stefan.ghinea@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/linux/kvm_host.h | 28 +++++++++++++++++++++++++++-
virt/kvm/kvm_main.c | 10 +++++-----
2 files changed, 32 insertions(+), 6 deletions(-)

--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -146,6 +146,7 @@ static inline bool is_error_page(struct
#define KVM_REQ_MMU_RELOAD (1 | KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
#define KVM_REQ_PENDING_TIMER 2
#define KVM_REQ_UNHALT 3
+#define KVM_REQ_VM_BUGGED (4 | KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
#define KVM_REQUEST_ARCH_BASE 8

#define KVM_ARCH_REQ_FLAGS(nr, flags) ({ \
@@ -505,6 +506,7 @@ struct kvm {
struct srcu_struct irq_srcu;
pid_t userspace_pid;
unsigned int max_halt_poll_ns;
+ bool vm_bugged;
};

#define kvm_err(fmt, ...) \
@@ -533,6 +535,31 @@ struct kvm {
#define vcpu_err(vcpu, fmt, ...) \
kvm_err("vcpu%i " fmt, (vcpu)->vcpu_id, ## __VA_ARGS__)

+bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req);
+static inline void kvm_vm_bugged(struct kvm *kvm)
+{
+ kvm->vm_bugged = true;
+ kvm_make_all_cpus_request(kvm, KVM_REQ_VM_BUGGED);
+}
+
+#define KVM_BUG(cond, kvm, fmt...) \
+({ \
+ int __ret = (cond); \
+ \
+ if (WARN_ONCE(__ret && !(kvm)->vm_bugged, fmt)) \
+ kvm_vm_bugged(kvm); \
+ unlikely(__ret); \
+})
+
+#define KVM_BUG_ON(cond, kvm) \
+({ \
+ int __ret = (cond); \
+ \
+ if (WARN_ON_ONCE(__ret && !(kvm)->vm_bugged)) \
+ kvm_vm_bugged(kvm); \
+ unlikely(__ret); \
+})
+
static inline bool kvm_dirty_log_manual_protect_and_init_set(struct kvm *kvm)
{
return !!(kvm->manual_dirty_log_protect & KVM_DIRTY_LOG_INITIALLY_SET);
@@ -850,7 +877,6 @@ void *kvm_mmu_memory_cache_alloc(struct
bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
struct kvm_vcpu *except,
unsigned long *vcpu_bitmap, cpumask_var_t tmp);
-bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req);
bool kvm_make_all_cpus_request_except(struct kvm *kvm, unsigned int req,
struct kvm_vcpu *except);
bool kvm_make_cpus_request_mask(struct kvm *kvm, unsigned int req,
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -3264,7 +3264,7 @@ static long kvm_vcpu_ioctl(struct file *
struct kvm_fpu *fpu = NULL;
struct kvm_sregs *kvm_sregs = NULL;

- if (vcpu->kvm->mm != current->mm)
+ if (vcpu->kvm->mm != current->mm || vcpu->kvm->vm_bugged)
return -EIO;

if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
@@ -3470,7 +3470,7 @@ static long kvm_vcpu_compat_ioctl(struct
void __user *argp = compat_ptr(arg);
int r;

- if (vcpu->kvm->mm != current->mm)
+ if (vcpu->kvm->mm != current->mm || vcpu->kvm->vm_bugged)
return -EIO;

switch (ioctl) {
@@ -3536,7 +3536,7 @@ static long kvm_device_ioctl(struct file
{
struct kvm_device *dev = filp->private_data;

- if (dev->kvm->mm != current->mm)
+ if (dev->kvm->mm != current->mm || dev->kvm->vm_bugged)
return -EIO;

switch (ioctl) {
@@ -3755,7 +3755,7 @@ static long kvm_vm_ioctl(struct file *fi
void __user *argp = (void __user *)arg;
int r;

- if (kvm->mm != current->mm)
+ if (kvm->mm != current->mm || kvm->vm_bugged)
return -EIO;
switch (ioctl) {
case KVM_CREATE_VCPU:
@@ -3960,7 +3960,7 @@ static long kvm_vm_compat_ioctl(struct f
struct kvm *kvm = filp->private_data;
int r;

- if (kvm->mm != current->mm)
+ if (kvm->mm != current->mm || kvm->vm_bugged)
return -EIO;
switch (ioctl) {
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT