libblkio 1.3.0 added support of "fd" property for virtio-blk-vhost-vdpa driver. In QEMU, starting from commit cad2ccc395 ("block/blkio: use qemu_open() to support fd passing for virtio-blk") we are using `blkio_get_int(..., "fd")` to check if the "fd" property is supported for all the virtio-blk-* driver.
Unfortunately that property is also available for those driver that do not support it, such as virtio-blk-vhost-user. Indeed now QEMU is failing if used with virtio-blk-vhost-user in this way: -blockdev node-name=drive0,driver=virtio-blk-vhost-user,path=vhost-user-blk.sock,cache.direct=on: Could not open 'vhost-user-blk.sock': No such device or address So, `blkio_get_int()` is not enough to check whether the driver supports the `fd` property or not. This is because the virito-blk common libblkio driver only checks whether or not `fd` is set during `blkio_connect()` and fails for those transports that do not support it (all except vhost-vdpa for now). So for now let's also check that the driver is virtio-blk-vhost-vdpa, since that's the only one that supports it. Fixes: cad2ccc395 ("block/blkio: use qemu_open() to support fd passing for virtio-blk") Reported-by: Qing Wang <qinw...@redhat.com> Signed-off-by: Stefano Garzarella <sgarz...@redhat.com> --- block/blkio.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/block/blkio.c b/block/blkio.c index 1798648134..ca1149042a 100644 --- a/block/blkio.c +++ b/block/blkio.c @@ -662,6 +662,7 @@ static int blkio_virtio_blk_common_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { const char *path = qdict_get_try_str(options, "path"); + const char *blkio_driver = bs->drv->protocol_name; BDRVBlkioState *s = bs->opaque; bool fd_supported = false; int fd, ret; @@ -676,7 +677,8 @@ static int blkio_virtio_blk_common_open(BlockDriverState *bs, return -EINVAL; } - if (blkio_get_int(s->blkio, "fd", &fd) == 0) { + if (strcmp(blkio_driver, "virtio-blk-vhost-vdpa") == 0 && + blkio_get_int(s->blkio, "fd", &fd) == 0) { fd_supported = true; } -- 2.41.0