At 02/29/2012 06:05 PM, Avi Kivity Wrote: > On 02/29/2012 11:58 AM, Daniel P. Berrange wrote: >>> >>> How about using a virtio-serial channel for this? You can transfer any >>> amount of information (including the dump itself). >> >> When the guest OS has crashed, any dumps will be done from the host >> OS using libvirt's core dump mechanism. The guest OS isn't involved >> and is likely too dead to be of any use anyway. Likewise it is >> quite probably too dead to work a virtio-serial channel or any >> similarly complex device. We're really just after the simplest >> possible notification that the guest kernel has paniced. > > If it's alive enough to panic, it's alive enough to kexec its kdump > kernel. After that it can do anything. > > Guest-internal dumps are more useful IMO that host-initiated dumps. In Yes, guest-internal dump is better than host dump. But the user may not start guest-internal dump or guest-internal dump failed. So we need the following feature: 1. If the guest-internal dump does not work, the guest's status is 'crashed'. And then the user does the host dump. 2. If the guest-internal dump is working, the guest's status should be 'dumping'. The user see this status and know the guest has paniced, and the guest-internal dump is working. Thanks Wen Congyang > a cloud, the host-initiated dump is left on the host, outside the reach > of the guest admin, outside the guest image where all the symbols are, > and sometimes not even on the same host if a live migration occurred. > It's more useful in small setups, or if the problem is in the > hypervisor, not 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