On Tue, Aug 28, 2012 at 2:58 PM, Stefan Hajnoczi <stefa...@linux.vnet.ibm.com> wrote: > It is possible to create an image that is larger than its backing file. > Reading beyond the end of the backing file produces zeroes if no writes > have been made to those sectors in the image file. > > This patch finishes streaming early when the end of the backing file is > reached. Without this patch the block job hangs and continually tries > to stream the first sectors beyond the end of the backing file. > > To reproduce the hung block job bug: > > $ qemu-img create -f qcow2 backing.qcow2 128M > $ qemu-img create -f qcow2 -o backing_file=backing.qcow2 image.qcow2 6G > $ qemu -drive if=virtio,cache=none,file=image.qcow2 > (qemu) block_stream virtio0 > (qemu) info block-jobs > > The qemu-iotests 030 streaming test still passes. > > Signed-off-by: Stefan Hajnoczi <stefa...@linux.vnet.ibm.com> > --- > block/stream.c | 7 +++++++ > 1 file changed, 7 insertions(+)
I will resend this along with a test case. Stefan
