On 08/25/2011 04:21 PM, Marcelo Tosatti wrote:
On Thu, Aug 25, 2011 at 07:42:10AM +0300, Avi Kivity wrote: > On 08/25/2011 05:04 AM, Marcelo Tosatti wrote: > >> > >> It could increase the flood count independently of the accessed bit of > >> the spte being updated, zapping after 3 attempts as it is now. > >> > >> But additionally reset the flood count if the gpte appears to be valid > >> (points to an existant gfn if the present bit is set, or if its zeroed). > > > >Well not zero, as thats a common pattern for non ptes. > > > > On 32-bit with 4GB RAM, practically anything is a valid gpte. The following could be required to consider a valid gpte, for write flood detection purposes: - Must be present. - PageCacheDisable must be unset. - PageWriteThrough must be unset.
Unless the guest is using PAT. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain. -- 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
