On 22/06/15 09:44, Peter Maydell wrote: > On 17 June 2015 at 10:00, Suzuki K. Poulose <suzuki.poulose@xxxxxxx> wrote: >> From: "Suzuki K. Poulose" <suzuki.poulose@xxxxxxx> >> >> This patch adds a generic ARM v8 KVM target cpu type for use >> by the new CPUs which eventualy ends up using the common sys_reg >> table. For backward compatibility the existing targets have been >> preserved. Any new target CPU that can be covered by generic v8 >> sys_reg tables should make use of the new generic target. > > How do you intend this to work for cross-host migration? It is not meant to work for cross migration at all. > Is the idea that the kernel guarantees that "generic" looks > 100% the same to the guest regardless of host hardware? I'm > not sure that can be made to work, given impdef differences > in ID register values, bp/wp registers, and so on. > > Given that, it seems to me that we still need to provide > KVM_ARM_TARGET_$THISCPU defines so userspace can request > a specific guest CPU flavour; so what does this patch > provide that isn't already provided by just having userspace > query for the "preferred" CPU type as it does already? The way I see this working is that a "generic" CPU cannot be migrated (because we don't know anything about it). If it can be identified as a known (non generic) implementation, then we can migrate it. M. -- Jazz is not dead. It just smells funny... -- 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
