On Aug 14, 2012, at 1:42 PM, Jan Kiszka wrote: > On 2012-08-14 10:56, Daniel P. Berrange wrote: >> On Mon, Aug 13, 2012 at 03:21:32PM -0300, Marcelo Tosatti wrote: >>> On Wed, Aug 08, 2012 at 10:43:01AM +0800, 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 >>> >>> How about searching for the "Kernel panic - not syncing" string >>> in the guests serial output? Say libvirtd could take an action upon >>> that? >> >> No, this is not satisfactory. It depends on the guest OS being >> configured to use the serial port for console output which we >> cannot mandate, since it may well be required for other purposes. > Please don't forget Windows guests, there is no console and no "Kernel Panic" string ;) What I used for debugging purposes on Windows guest is to register a bugcheck callback in virtio-net driver and write 1 to VIRTIO_PCI_ISR register. Yan. > Well, we have more than a single serial port, even when leaving > virtio-serial aside... > > Jan > > -- > Siemens AG, Corporate Technology, CT RTC ITP SDP-DE > Corporate Competence Center Embedded Linux > -- > 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 -- 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
