netdev - Re: [PATCH 08/17] nfp: no need to check return value of debugfs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190806103035.60bacd35@cakuba.netronome.com>
Date:   Tue, 6 Aug 2019 10:30:35 -0700
From:   Jakub Kicinski <jakub.kicinski@...ronome.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:     netdev@...r.kernel.org, "David S. Miller" <davem@...emloft.net>,
        Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        Jesper Dangaard Brouer <hawk@...nel.org>,
        John Fastabend <john.fastabend@...il.com>,
        Edwin Peer <edwin.peer@...ronome.com>,
        Yangtao Li <tiny.windzz@...il.com>,
        Simon Horman <simon.horman@...ronome.com>,
        oss-drivers@...ronome.com
Subject: Re: [PATCH 08/17] nfp: no need to check return value of
 debugfs_create functions

On Tue, 6 Aug 2019 19:00:49 +0200, Greg Kroah-Hartman wrote:
> On Tue, Aug 06, 2019 at 09:50:08AM -0700, Jakub Kicinski wrote:
> > On Tue,  6 Aug 2019 18:11:19 +0200, Greg Kroah-Hartman wrote:  
> > > When calling debugfs functions, there is no need to ever check the
> > > return value.  The function can work or not, but the code logic should
> > > never do something different based on this.
> > > 
> > > Cc: Jakub Kicinski <jakub.kicinski@...ronome.com>
> > > Cc: "David S. Miller" <davem@...emloft.net>
> > > Cc: Alexei Starovoitov <ast@...nel.org>
> > > Cc: Daniel Borkmann <daniel@...earbox.net>
> > > Cc: Jesper Dangaard Brouer <hawk@...nel.org>
> > > Cc: John Fastabend <john.fastabend@...il.com>
> > > Cc: Edwin Peer <edwin.peer@...ronome.com>
> > > Cc: Yangtao Li <tiny.windzz@...il.com>
> > > Cc: Simon Horman <simon.horman@...ronome.com>
> > > Cc: oss-drivers@...ronome.com
> > > Cc: netdev@...r.kernel.org
> > > Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>  
> > 
> > Acked-by: Jakub Kicinski <jakub.kicinski@...ronome.com>
> > 
> > I take it this is the case since commit ff9fb72bc077 ("debugfs: return
> > error values, not NULL")? I.e. v5.0? It'd be useful to know for backport
> > purposes.  
> 
> You were always safe to ignore debugfs calls before that, but in 5.0 and
> then 5.2 we got a bit more "robust" with some internal debugfs logic to
> make it even easier.  These can be backported to 2.6.11+ if you really
> want to, no functionality should change.

Oh sorry! I meant vendor out-of-tree driver backport. We all maintain 
a tarball version of the drivers that compile on old kernels, I was
mostly wondering from that perspective.
 
> But why would you want to backport them?  This really isn't a "bugfix"
> for a stable kernel.  No one should ever noticed the difference except
> for less memory being used.

Right, it wouldn't really help to do an upstream backport.