"Michael S. Tsirkin" <[email protected]> writes: > On Tue, Nov 17, 2015 at 08:52:24AM +0100, Markus Armbruster wrote: >> "Michael S. Tsirkin" <[email protected]> writes: >> >> > When we get an unexpected response, print out >> > the original request. >> > Helps debug protocol errors tremendously. >> > >> > Signed-off-by: Michael S. Tsirkin <[email protected]> >> > --- >> > >> > Changes from v1: add missing . >> > >> > 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 3404b81..5bc6c45 100644 >> > --- a/hw/virtio/vhost-user.c >> > +++ b/hw/virtio/vhost-user.c >> > @@ -121,8 +121,8 @@ static int vhost_user_read(struct vhost_dev *dev, >> > VhostUserMsg *msg) >> > >> > r = qemu_chr_fe_read_all(chr, p, size); >> > if (r != size) { >> > - error_report("Failed to read msg header. Read %d instead of %d.", >> > r, >> > - size); >> > + error_report("Failed to read msg header. Read %d instead of %d." >> > + " Original request %d.", r, size, msg->request); >> > goto fail; >> > } >> >> Error message style nit: the error message proper (the thing emitted by >> error_report()) should be a phrase, and it should be short and to the >> point. It can be followed by hints. Compare: >> >> qemu-system-x86_64: Failed to read msg header. Read 11 instead >> of 12. Original request 1. >> >> and >> >> qemu-system-x86_64: Failed to read msg header >> Read 11 instead of 12 for request 1. >> >> I prefer the latter. The error message proper is short and to the >> point. The hint adds information, which happens to be useful mainly to >> developers. Sensible line lengths. >> >> By the way, the error.h API supports this message + hints convention >> since commit 50b7b00. >> >> See also >> Message-ID: <[email protected]> >> http://lists.gnu.org/archive/html/qemu-devel/2015-11/msg01662.html > > Oh that's nice. There are more cases like this in vhost-user. > Let's rework them all past 2.5?
Okay. Several ones in 2.6 is better than just one now :)
