On Fri, 2010-12-31 at 17:10 +0800, Jan Kiszka wrote: > Am 31.12.2010 06:22, Huang Ying wrote: > > In Linux kernel HWPoison processing implementation, the virtual > > address in processes mapping the error physical memory page is marked > > as HWPoison. So that, the further accessing to the virtual > > address will kill corresponding processes with SIGBUS. > > > > If the error physical memory page is used by a KVM guest, the SIGBUS > > will be sent to QEMU, and QEMU will simulate a MCE to report that > > memory error to the guest OS. If the guest OS can not recover from > > the error (for example, the page is accessed by kernel code), guest OS > > will reboot the system. But because the underlying host virtual > > address backing the guest physical memory is still poisoned, if the > > guest system accesses the corresponding guest physical memory even > > after rebooting, the SIGBUS will still be sent to QEMU and MCE will be > > simulated. That is, guest system can not recover via rebooting. > > > > In fact, across rebooting, the contents of guest physical memory page > > need not to be kept. We can allocate a new host physical page to > > back the corresponding guest physical address. > > > > This patch fixes this issue in QEMU-KVM via calling qemu_ram_remap() > > to clear the corresponding page table entry, so that make it possible > > to allocate a new page to recover the issue. > > > > Signed-off-by: Huang Ying <ying.huang@xxxxxxxxx> > > --- > > kvm.h | 2 ++ > > qemu-kvm.c | 37 +++++++++++++++++++++++++++++++++++++ > > What's missing in upstream to make this a uq/master patch? We are still > piling up features and fixes in qemu-kvm* that should better target > upstream directly. That's work needlessly done twice. OK. I will do that. Just based on uq/master is sufficient to make it an upstream patch? > Is this infrastructure really arch-independent? Will there be other > users besides x86? If not, better keep it in target-i386/kvm.c. No. It is used only in x86. I will move it into target-i386/kvm.c. Best Regards, Huang Ying -- 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
