| Message ID | 1484621964-187372-1-git-send-email-longpeng2@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jan 17, 2017 at 10:59:24AM +0800, Longpeng(Mike) wrote: > As qvring_indirect_desc_setup() wouldn't initialize last vring_desc, > so it's filled with dirty data, this might cause virtio backend broken. > > For example, the last bit of this vring_desc's flags might be 1, so > virtqueue_read_next_desc() would report "Desc next is ***". > > Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com> > > --- > Changes since v1: > - use writel() for @len as it's 32 bits long. [Stefan] > > --- > tests/libqos/virtio.c | 8 ++++++++ > 1 file changed, 8 insertions(+) Thanks, applied to my block-next tree: https://github.com/stefanha/qemu/commits/block-next Stefan
diff --git a/tests/libqos/virtio.c b/tests/libqos/virtio.c index ec30cb9..02e6a43 100644 --- a/tests/libqos/virtio.c +++ b/tests/libqos/virtio.c @@ -171,12 +171,20 @@ QVRingIndirectDesc *qvring_indirect_desc_setup(QVirtioDevice *d, for (i = 0; i < elem - 1; ++i) { /* indirect->desc[i].addr */ writeq(indirect->desc + (16 * i), 0); + /* indirect->desc[i].len */ + writel(indirect->desc + (16 * i) + 8, 0); /* indirect->desc[i].flags */ writew(indirect->desc + (16 * i) + 12, VRING_DESC_F_NEXT); /* indirect->desc[i].next */ writew(indirect->desc + (16 * i) + 14, i + 1); } + /* zeroed last element */ + writeq(indirect->desc + (16 * i), 0); /* addr */ + writel(indirect->desc + (16 * i) + 8, 0); /* len */ + writew(indirect->desc + (16 * i) + 12, 0); /* flags */ + writew(indirect->desc + (16 * i) + 14, 0); /* next */ + return indirect; }
As qvring_indirect_desc_setup() wouldn't initialize last vring_desc, so it's filled with dirty data, this might cause virtio backend broken. For example, the last bit of this vring_desc's flags might be 1, so virtqueue_read_next_desc() would report "Desc next is ***". Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com> --- Changes since v1: - use writel() for @len as it's 32 bits long. [Stefan] --- tests/libqos/virtio.c | 8 ++++++++ 1 file changed, 8 insertions(+)