On 07/21/2012 10:44 AM, Wen Congyang wrote: > We can know the guest is panicked when the guest runs on xen. > But we do not have such feature on kvm. > > Another purpose of this feature is: management app(for example: > libvirt) can do auto dump when the guest is panicked. If management > app does not do auto dump, the guest's user can do dump by hand if > he sees the guest is panicked. > > We have three solutions to implement this feature: > 1. use vmcall > 2. use I/O port > 3. use virtio-serial. > > We have decided to avoid touching hypervisor. The reason why I choose > choose the I/O port is: > 1. it is easier to implememt > 2. it does not depend any virtual device > 3. it can work when starting the kernel Was the option of implementing a virtio-watchdog driver considered? You're basically re-implementing a watchdog, a guest-host interface and a set of protocols for guest-host communications. Why can't we re-use everything we have now, push a virtio watchdog driver into drivers/watchdog/, and gain a more complete solution to detecting hangs inside the guest. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html