On Mo, 2015-07-13 at 10:36 +0300, Michael S. Tsirkin wrote: > On Mon, Jul 13, 2015 at 01:46:47PM +0800, Jason Wang wrote: > > We abort on unaligned read/write in > > virtio_address_space_read()/write() but since len in under control of > > guest so qemu will simply crash when booting a modern guest (guest is > > try to read when len is zero). > > read. > > How can len be 0? Isn't this a guest bug? Or is this > a theoretical issue?
Something dumping pci config space? With pci access capability not being used before and therefore zeroed? Then hitting the "data" field will trigger a zero-length read. That assert actually triggers when booting a recent linux kernel with disable-modern=off cheers, Gerd
