From mboxrd@z Thu Jan  1 00:00:00 1970
From: Martin Wilck <martin.wilck@suse.com>
Subject: Re: [RFC PATCH v2 3/3] libmultipath: change log level
 for null uid_attribute
Date: Thu, 24 Sep 2020 08:06:41 +0000
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On Wed, 2020-09-23 at 23:59 -0500, Benjamin Marzinski wrote:
> If uid_attribute is explicitly set to an empty string, multipath
> should
> log the uid at the default log level, since using the fallback code
> is
> the expected behavior.
>=20
> Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
> ---
>  libmultipath/discovery.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>=20
> diff --git a/libmultipath/discovery.c b/libmultipath/discovery.c
> index f650534f..435f2639 100644
> --- a/libmultipath/discovery.c
> +++ b/libmultipath/discovery.c
> @@ -2091,7 +2091,8 @@ get_uid (struct path * pp, int path_state,
> struct udev_device *udev,
>  =09=09}
>  =09=09if ((!udev_available || (len <=3D 0 && allow_fallback))
>  =09=09    && has_uid_fallback(pp)) {
> -=09=09=09used_fallback =3D 1;
> +=09=09=09if (udev_available || !(udev && pp-
> >uid_attribute))
> +=09=09=09=09used_fallback =3D 1;
>  =09=09=09len =3D uid_fallback(pp, path_state, &origin);
>  =09=09}
>  =09}

Uff, this logic was convoluted anyway, now it's even harder to grasp.
IIUC, if !udev, used_fallback will be set to 1, even if=20
pp->uid_attribute is the empty string. Is that intended?
To make this easier to read, I'd suggest something like this:

=09=09bool valid_uid_attr =3D pp->uid_attribute
=09=09=09&& *pp->uid_attribute;
=09=09bool empty_uid_attr =3D pp->uid_attribute
=09=09=09&& !*pp->uid_attribute;
=09=09bool udev_available =3D udev && valid_uid_attr;
      ...
=09=09if ((!udev_available || (len <=3D 0 && allow_fallback))
=09=09    && has_uid_fallback(pp)) {
=09=09=09if (!empty_uid_attr)
=09=09=09=09used_fallback =3D 1;
=09=09=09len =3D uid_fallback(pp, path_state, &origin);

Regards,
Martin

--=20
Dr. Martin Wilck <mwilck@suse.com>, Tel. +49 (0)911 74053 2107
SUSE  Software Solutions Germany GmbH
HRB 36809, AG N=FCrnberg GF: Felix
Imend=F6rffer