On Wed, Aug 21, 2013 at 12:42:37PM +0300, Michael S. Tsirkin wrote: > On Wed, Aug 21, 2013 at 10:18:23AM +0200, Paolo Bonzini wrote: > > Il 21/08/2013 10:03, Marcel Apfelbaum ha scritto: > > > On Wed, 2013-08-14 at 10:02 +0300, Ronen Hod wrote: > > >> How about adding a flag that tells QEMU whether to pause or reboot the > > >> guest > > >> after the panic? > > >> We cannot assume that we always have a management layer that takes care > > >> of this. > > >> One example is Microsoft's WHQL that deliberately generates a BSOD, and > > >> then > > >> examines the dump files. > > > After this patch the pvpanic is not part of the global devices anymore so > > > just > > > don't enable it if you want to reboot on BSOD. > > > In my opinion "reboot after panic" equals "run without pvpanic device" > > > > This is not entirely possible, since "reboot after panic" is a guest > > setting while "run without pvpanic device" is a host setting (that the > > guest administrator may not even have access to: Ronen's case is a good > > example of this, because the "administrator" there is the WHQL harness). > > > > However, I think this is a driver problem. The driver should just probe > > the "reboot after panic" setting and not issue the outb to the pvpanic port. > > > > Paolo > > This might or might not be possible on different OS-es. > What exactly is gained by doing vmstop on outb of pvpanic?
This gives management apps (libvirt) a chance to take care of the situation. It can reboot, poweroff, or dump guest. > We want a notification about the panic but > adding yet another way to halt seems kind of useless. > Why not let VM continue? If it wants to stop it > can always call halt. >