Jan Kiszka wrote: > Marcelo Tosatti wrote: >> On Thu, Feb 04, 2010 at 01:33:50AM +0100, Jan Kiszka wrote: >>> Marcelo Tosatti wrote: >>>> On Wed, Feb 03, 2010 at 10:29:45PM +0100, Jan Kiszka wrote: >>>>> So far we synchronized any dirty VCPU state back into the kernel before >>>>> updating the guest debug state. This was a tribute to a deficit in x86 >>>>> kernels before 2.6.33. But as this is an arch-dependent issue, it is >>>>> better handle in the x86 part of KVM and remove the writeback point for >>>>> generic code. >>>> Jan, >>>> >>>> This patch breaks migration. >>> Can you elaborate what you did? I can't reproduce, and I do not see any >>> conceptual issue (given that guest debugging conflicts with migration >>> anyway). >> kvm-autotest fails (migration only, install is ok, both Linux and Win >> guests). Not sure why, perhaps the unconditional KVM_SET_GUEST_DEBUG >> corrupts state somehow? >> >> Tested with io thread enabled. > > That's this default-off thing, so... OK, confirmed, investigating. >
Heisenbug: It first also popped up (in form of a frozen migration target) after removing this patch, but now it's totally unreproducible, whatever patch I apply or revert from my series. Base is current master. I tend to think there is a hidden issue of iothread vs. migration, unrelated to this patch. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html