On 3 December 2014 at 21:18, Christoffer Dall <christoffer.dall@xxxxxxxxxx> wrote: > Several people have reported problems with rebooting ARM VMs, especially > on 32-bit ARM. This is mainly due to the same reason we were seeing > boot errors in the past, namely that the ram, dcache, and icache weren't > coherent on guest boot with the guest (stage-1) MMU disabled. We solved > this by ensuring coherency when we fault in pages, but since most memory > is already mapped after a reboot, we don't do anything. > > The solution is to unmap the regular RAM on VCPU init, but we must > take care to not unmap the GIC or other IO regions, hence the somehwat > complicated solution. > > As part of figuring this out, it became clear that some semantics around > the KVM_ARM_VCPU_INIT ABI and system event ABI was unclear (what is > userspace expected to do when it receives a system event). This series > also clarifies the ABI and changes the kernel functionality to do what > userspace expects (turn off VCPUs on a system shutdown event). Userspace ABI documentation clarifications: Reviewed-by: Peter Maydell <peter.maydell@xxxxxxxxxx> -- PMM -- 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
