[RFC PATCH 09/67] KVM: Add infrastructure and macro to mark VM as bugged

[isaku . yamahata]

From: Sean Christopherson <sean.j.christopher...@intel.com>

Signed-off-by: Sean Christopherson <sean.j.christopher...@intel.com>
---
 include/linux/kvm_host.h | 27 +++++++++++++++++++++++++++
 virt/kvm/kvm_main.c      | 10 +++++-----
 2 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 7f2e2a09ebbd..03c016ff1715 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -146,6 +146,7 @@ static inline bool is_error_page(struct page *page)
 #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 +506,8 @@ 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 +536,30 @@ struct kvm {
 #define vcpu_err(vcpu, fmt, ...)                                       \
        kvm_err("vcpu%i " fmt, (vcpu)->vcpu_id, ## __VA_ARGS__)
 
+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);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 11166e901582..21af4f083674 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -3194,7 +3194,7 @@ static long kvm_vcpu_ioctl(struct file *filp,
        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))
@@ -3400,7 +3400,7 @@ static long kvm_vcpu_compat_ioctl(struct file *filp,
        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) {
@@ -3466,7 +3466,7 @@ static long kvm_device_ioctl(struct file *filp, unsigned 
int ioctl,
 {
        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) {
@@ -3682,7 +3682,7 @@ static long kvm_vm_ioctl(struct file *filp,
        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:
@@ -3877,7 +3877,7 @@ static long kvm_vm_compat_ioctl(struct file *filp,
        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) {
        case KVM_GET_DIRTY_LOG: {
-- 
2.17.1