diff options
Diffstat (limited to 'Documentation/virt/kvm/api.rst')
| -rw-r--r-- | Documentation/virt/kvm/api.rst | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 9edd9e436bab..27d945d5b4e4 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -6848,6 +6848,26 @@ spec refer, https://github.com/riscv/riscv-sbi-doc. :: + /* KVM_EXIT_MEMORY_FAULT */ + struct { + __u64 flags; + __u64 gpa; + __u64 size; + } memory_fault; + +KVM_EXIT_MEMORY_FAULT indicates the vCPU has encountered a memory fault that +could not be resolved by KVM. The 'gpa' and 'size' (in bytes) describe the +guest physical address range [gpa, gpa + size) of the fault. The 'flags' field +describes properties of the faulting access that are likely pertinent. +Currently, no flags are defined. + +Note! KVM_EXIT_MEMORY_FAULT is unique among all KVM exit reasons in that it +accompanies a return code of '-1', not '0'! errno will always be set to EFAULT +or EHWPOISON when KVM exits with KVM_EXIT_MEMORY_FAULT, userspace should assume +kvm_run.exit_reason is stale/undefined for all other error numbers. + +:: + /* KVM_EXIT_NOTIFY */ struct { #define KVM_NOTIFY_CONTEXT_INVALID (1 << 0) @@ -7880,6 +7900,27 @@ This capability is aimed to mitigate the threat that malicious VMs can cause CPU stuck (due to event windows don't open up) and make the CPU unavailable to host or other VMs. +7.34 KVM_CAP_MEMORY_FAULT_INFO +------------------------------ + +:Architectures: x86 +:Returns: Informational only, -EINVAL on direct KVM_ENABLE_CAP. + +The presence of this capability indicates that KVM_RUN will fill +kvm_run.memory_fault if KVM cannot resolve a guest page fault VM-Exit, e.g. if +there is a valid memslot but no backing VMA for the corresponding host virtual +address. + +The information in kvm_run.memory_fault is valid if and only if KVM_RUN returns +an error with errno=EFAULT or errno=EHWPOISON *and* kvm_run.exit_reason is set +to KVM_EXIT_MEMORY_FAULT. + +Note: Userspaces which attempt to resolve memory faults so that they can retry +KVM_RUN are encouraged to guard against repeatedly receiving the same +error/annotated fault. + +See KVM_EXIT_MEMORY_FAULT for more information. + 8. Other capabilities. ====================== |