On Wed, Jun 05, 2013 at 07:08:44PM -0400, Luiz Capitulino wrote: > On Wed, 5 Jun 2013 18:24:49 -0300 > Rafael Aquini <aquini@xxxxxxxxxx> wrote: > > > On Wed, Jun 05, 2013 at 05:10:31PM -0400, Luiz Capitulino wrote: > > > The balloon_page_dequeue() function can return NULL. If it does for > > > the first page being freed, then leak_balloon() will create a > > > scatter list with len=0. Which in turn seems to generate an invalid > > > virtio request. > > > > > > Signed-off-by: Luiz Capitulino <lcapitulino@xxxxxxxxxx> > > > --- > > > > > > PS: I didn't get this in practice. I found it by code review. On the other > > > hand, automatic-ballooning was able to put such invalid requests in > > > the virtqueue and QEMU would explode... > > > > > > > Nice catch! The patch looks sane and replicates the check done at > > fill_balloon(). I think we also could use this P.S. as a commentary > > to let others aware of this scenario. Thanks Luiz! > > Want me to respin? > That would be great, indeed. I guess the commentary could also go for the same if case at fill_balloon(), assuming the tests are placed to prevent the same scenario you described at changelog. You can stick my Ack on it, if reposting. Cheers! -- Rafael -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>