search for: kvmi_recv

On 09/08/19 17:59, Adalbert Laz?r wrote: > +static int kvmi_recv(void *arg) > +{ > + struct kvmi *ikvm = arg; > + > + kvmi_info(ikvm, "Hooking VM\n"); > + > + while (kvmi_msg_process(ikvm)) > + ; > + > + kvmi_info(ikvm, "Unhooking VM\n"); > + > + kvmi_end_introspection(ikvm); > + > + return 0; > +} &...

...g for POLLHUP. */ + kvmi_sock_shutdown(ikvm); + + /* + * At this moment the socket is shut down, no more commands will come + * from the introspector, and the only way into the introspection is + * thru the event handlers. Make sure the introspection ends. + */ + kvmi_put(kvm); +} + +static int kvmi_recv(void *arg) +{ + struct kvmi *ikvm = arg; + + kvmi_info(ikvm, "Hooking VM\n"); + + while (kvmi_msg_process(ikvm)) + ; + + kvmi_info(ikvm, "Unhooking VM\n"); + + kvmi_end_introspection(ikvm); + + return 0; +} + +int kvmi_hook(struct kvm *kvm, const struct kvm_introspection *qemu)...

...rmance critical, >> so make those the restricted/slow flows, e.g. force userspace to quiesce >> the VM by making unhook() mutually exclusive with every vcpu ioctl() and >> maybe anything that takes kvm->lock. >> >> Then kvmi_ioctl_unhook() can use thread_stop() and kvmi_recv() just needs >> to check kthread_should_stop(). >> >> That way kvmi doesn't need to be refcounted since it's guaranteed to be >> alive if the pointer is non-null. Eliminating the refcounting will clean >> up a lot of the code by eliminating calls to kvmi_{get,...

...;> so make those the restricted/slow flows, e.g. force userspace to quiesce > >> the VM by making unhook() mutually exclusive with every vcpu ioctl() and > >> maybe anything that takes kvm->lock. > >> > >> Then kvmi_ioctl_unhook() can use thread_stop() and kvmi_recv() just needs > >> to check kthread_should_stop(). > >> > >> That way kvmi doesn't need to be refcounted since it's guaranteed to be > >> alive if the pointer is non-null. Eliminating the refcounting will clean > >> up a lot of the code by elimin...

...ook are relatively rare events and not performance critical, so make those the restricted/slow flows, e.g. force userspace to quiesce the VM by making unhook() mutually exclusive with every vcpu ioctl() and maybe anything that takes kvm->lock. Then kvmi_ioctl_unhook() can use thread_stop() and kvmi_recv() just needs to check kthread_should_stop(). That way kvmi doesn't need to be refcounted since it's guaranteed to be alive if the pointer is non-null. Eliminating the refcounting will clean up a lot of the code by eliminating calls to kvmi_{get,put}(), e.g. wrappers like kvmi_breakpoint_e...

The KVM introspection subsystem provides a facility for applications running on the host or in a separate VM, to control the execution of other VM-s (pause, resume, shutdown), query the state of the vCPUs (GPRs, MSRs etc.), alter the page access bits in the shadow page tables (only for the hardware backed ones, eg. Intel's EPT) and receive notifications when events of interest have taken place

The KVM introspection subsystem provides a facility for applications running on the host or in a separate VM, to control the execution of other VM-s (pause, resume, shutdown), query the state of the vCPUs (GPRs, MSRs etc.), alter the page access bits in the shadow page tables (only for the hardware backed ones, eg. Intel's EPT) and receive notifications when events of interest have taken place