On Thu, Jun 27, 2013 at 12:01:10PM +0300, Gleb Natapov wrote: > On Thu, Jun 27, 2013 at 11:29:00AM +0300, Gleb Natapov wrote: > > On Fri, Jun 07, 2013 at 04:51:26PM +0800, Xiao Guangrong wrote: > > > This patch tries to introduce a very simple and scale way to invalidate > > > all mmio sptes - it need not walk any shadow pages and hold mmu-lock > > > > > > KVM maintains a global mmio valid generation-number which is stored in > > > kvm->memslots.generation and every mmio spte stores the current global > > > generation-number into his available bits when it is created > > > > > > When KVM need zap all mmio sptes, it just simply increase the global > > > generation-number. When guests do mmio access, KVM intercepts a MMIO #PF > > > then it walks the shadow page table and get the mmio spte. If the > > > generation-number on the spte does not equal the global generation-number, > > > it will go to the normal #PF handler to update the mmio spte > > > > > > Since 19 bits are used to store generation-number on mmio spte, we zap all > > > mmio sptes when the number is round > > > > > So this commit makes Fedora 9 32 bit reboot during boot, Fedora 9 64 > > fails too, but I haven't checked what happens exactly. > > > Something wrong with gfn calculation during mmio: > > qemu-system-x86-17003 [000] 3962.625103: handle_mmio_page_fault: addr:c00ba6c0 gfn 100000000ba access a92 > qemu-system-x86-17003 [000] 3962.774862: handle_mmio_page_fault: addr:ffffb170 gfn 100000fee00 access a92 > Hmm, so I wounder why get_mmio_spte_gfn() does not clear gen bits. -- Gleb. -- 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
