During protocol negotiation, when we the QEMU stub does not support a backend with F_CONFIG, it throws a warning and supresses the VHOST_USER_PROTOCOL_F_CONFIG bit.
However, the warning uses warn_reportf_err macro and passes an unitialized errp pointer. However, the macro tries to edit the 'msg' member of the unitialized Error and segfaults. Instead, just use warn_report, which prints a warning message directly to the output. Fixes: 5653493 ("hw/virtio/vhost-user: don't suppress F_CONFIG when supported") Signed-off-by: Albert Esteve <aest...@redhat.com> --- hw/virtio/vhost-user.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index e68daa35d4..34c331b3ba 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -2031,8 +2031,8 @@ static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque, } else { if (virtio_has_feature(protocol_features, VHOST_USER_PROTOCOL_F_CONFIG)) { - warn_reportf_err(*errp, "vhost-user backend supports " - "VHOST_USER_PROTOCOL_F_CONFIG but QEMU does not."); + warn_report("vhost-user backend supports " + "VHOST_USER_PROTOCOL_F_CONFIG but QEMU does not."); protocol_features &= ~(1ULL << VHOST_USER_PROTOCOL_F_CONFIG); } } -- 2.39.1