[RFC PATCH 1/3] KVM: Export kvm_make_all_cpus_request() for use in marking VMs as bugged

Sean Christopherson
2020-09-23T22:45:40Z

Export kvm_make_all_cpus_request() and hoist the request helper
declarations of request up to the KVM_REQ_* definitions in preparation
for adding a "VM bugged" framework. The framework will add KVM_BUG()
and KVM_BUG_ON() as alternatives to full BUG()/BUG_ON() for cases where
KVM has definitely hit a bug (in itself or in silicon) and the VM is all
but guaranteed to be hosed. Marking a VM bugged will trigger a request
to all vCPUs to allow arch code to forcefully evict each vCPU from its
run loop.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
include/linux/kvm_host.h | 18 +++++++++---------
virt/kvm/kvm_main.c | 1 +
2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 05e3c2fb3ef7..1d70aeeb7ec3 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -154,6 +154,15 @@ static inline bool is_error_page(struct page *page)
})
#define KVM_ARCH_REQ(nr) KVM_ARCH_REQ_FLAGS(nr, 0)

+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,
+ unsigned long *vcpu_bitmap);
+
#define KVM_USERSPACE_IRQ_SOURCE_ID 0
#define KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID 1

@@ -845,15 +854,6 @@ void kvm_mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc);
void *kvm_mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc);
#endif

-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,
- unsigned long *vcpu_bitmap);
-
long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg);
long kvm_arch_vcpu_ioctl(struct file *filp,
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index cf88233b819a..bf3f333c7a19 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -306,6 +306,7 @@ bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
{
return kvm_make_all_cpus_request_except(kvm, req, NULL);
}
+EXPORT_SYMBOL_GPL(kvm_make_all_cpus_request);

#ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
void kvm_flush_remote_tlbs(struct kvm *kvm)
--
2.28.0