On Thu, Feb 29, 2024 at 06:25:40PM +0100, Thomas Huth wrote:
> On 29/02/2024 15.38, Zhao Liu wrote:
> > From: Zhao Liu <zhao1....@intel.com>
> >
> > As the comment in qapi/error, passing @errp to error_prepend() requires
> > ERRP_GUARD():
> >
> > * = Why, when and how to use ERRP_GUARD() =
> > *
> > * Without ERRP_GUARD(), use of the @errp parameter is restricted:
> > ...
> > * - It should not be passed to error_prepend(), error_vprepend() or
> > * error_append_hint(), because that doesn't work with &error_fatal.
> > * ERRP_GUARD() lifts these restrictions.
> > *
> > * To use ERRP_GUARD(), add it right at the beginning of the function.
> > * @errp can then be used without worrying about the argument being
> > * NULL or &error_fatal.
> >
> > ERRP_GUARD() could avoid the case when @errp is the pointer of
> > error_fatal, the user can't see this additional information, because
> > exit() happens in error_setg earlier than information is added [1].
> >
> > The xen_netdev_connect() passes @errp to error_prepend(), and its @errp
> > parameter is from xen_device_frontend_changed().
> >
> > Though its @errp points to @local_err of xen_device_frontend_changed(),
> > to follow the requirement of @errp, add missing ERRP_GUARD() at the
> > beginning of this function.
> >
> > [1]: Issue description in the commit message of commit ae7c80a7bd73
> > ("error: New macro ERRP_GUARD()").
> >
> > Cc: Stefano Stabellini <sstabell...@kernel.org>
> > Cc: Anthony Perard <anthony.per...@citrix.com>
> > Cc: Paul Durrant <p...@xen.org>
> > Cc: Jason Wang <jasow...@redhat.com>
> > Signed-off-by: Zhao Liu <zhao1....@intel.com>
> > ---
> > hw/net/xen_nic.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/hw/net/xen_nic.c b/hw/net/xen_nic.c
> > index 453fdb981983..89487b49baf9 100644
> > --- a/hw/net/xen_nic.c
> > +++ b/hw/net/xen_nic.c
> > @@ -351,6 +351,7 @@ static bool net_event(void *_xendev)
> > static bool xen_netdev_connect(XenDevice *xendev, Error **errp)
> > {
> > + ERRP_GUARD();
> > XenNetDev *netdev = XEN_NET_DEVICE(xendev);
> > unsigned int port, rx_copy;
>
> Reviewed-by: Thomas Huth <th...@redhat.com>
Acked-by: Anthony PERARD <anthony.per...@citrix.com>
Thanks,
--
Anthony PERARD
