From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Howells <dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Subject: Re: [PATCH 3/3] p9auth: add p9auth driver
Date: Wed, 21 Apr 2010 11:49:15 +0100
Message-ID: <23120.1271846955@redhat.com>
References: <20100421012908.GB24251@us.ibm.com> <20100421012749.GA21338@us.ibm.com>
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To: "Serge E. Hallyn" <serue-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
Cc: dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, lkml <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Ashwin Ganti <ashwin.ganti-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Greg KH <greg-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>, rsc-kPPrOchjzlEAvxtiuMwx3w@public.gmane.org, ericvh-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Ron Minnich <rminnich-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, jt.beard-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Andrew Morgan <morgan-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, oleg-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org, Eric Paris <eparis-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Randy Dunlap <rdunlap-/UHa2rfvQTnk1uMJSBkQmQ@public.gmane.org>
List-Id: linux-api@vger.kernel.org

Serge E. Hallyn <serue-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org> wrote:

> +	if (ret == 0)
> +		commit_creds(new);
> +	else
> +		abort_creds(new);
> +
> +	return ret;

If you make this:

	if (ret == 0)
		return commit_creds(new);
	abort_creds(new);
	return ret;

then gcc can tail-call commit_creds(), which is guaranteed to return 0.

David