linux-kernel - Re: [PATCH v3 2/4] vhost-vdpa: introduce STOP backend feature bit

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: <20220526190630.GJ2168@kadam>
Date:   Thu, 26 May 2022 22:06:30 +0300
From:   Dan Carpenter <dan.carpenter@...cle.com>
To:     Eugenio Perez Martin <eperezma@...hat.com>
Cc:     Stefano Garzarella <sgarzare@...hat.com>,
        "Dawar, Gautam" <gautam.dawar@....com>,
        "Michael S. Tsirkin" <mst@...hat.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "kvm@...r.kernel.org" <kvm@...r.kernel.org>,
        "virtualization@...ts.linux-foundation.org" 
        <virtualization@...ts.linux-foundation.org>,
        Jason Wang <jasowang@...hat.com>,
        Zhu Lingshan <lingshan.zhu@...el.com>,
        "martinh@...inx.com" <martinh@...inx.com>,
        "ecree.xilinx@...il.com" <ecree.xilinx@...il.com>,
        Eli Cohen <elic@...dia.com>, Parav Pandit <parav@...dia.com>,
        Wu Zongyong <wuzongyong@...ux.alibaba.com>,
        "dinang@...inx.com" <dinang@...inx.com>,
        Christophe JAILLET <christophe.jaillet@...adoo.fr>,
        Xie Yongji <xieyongji@...edance.com>,
        "lulu@...hat.com" <lulu@...hat.com>,
        "martinpo@...inx.com" <martinpo@...inx.com>,
        "pabloc@...inx.com" <pabloc@...inx.com>,
        Longpeng <longpeng2@...wei.com>,
        "Piotr.Uminski@...el.com" <Piotr.Uminski@...el.com>,
        "Kamde, Tanuj" <tanuj.kamde@....com>,
        Si-Wei Liu <si-wei.liu@...cle.com>,
        "habetsm.xilinx@...il.com" <habetsm.xilinx@...il.com>,
        "lvivier@...hat.com" <lvivier@...hat.com>,
        Zhang Min <zhang.min9@....com.cn>,
        "hanand@...inx.com" <hanand@...inx.com>
Subject: Re: [PATCH v3 2/4] vhost-vdpa: introduce STOP backend feature bit

On Thu, May 26, 2022 at 07:00:06PM +0200, Eugenio Perez Martin wrote:
> > It feels like returning any literal that isn't 1 or 0 should trigger a
> > warning...  I've written that and will check it out tonight.
> >
> 
> I'm not sure this should be so strict, or "literal" does not include pointers?
> 

What I mean in exact terms, is that if you're returning a known value
and the function returns bool then the known value should be 0 or 1.
Don't "return 3;".  This new warning will complain if you return a known
pointer as in "return &a;".  It won't complain if you return an
unknown pointer "return p;".

> As an experiment, can Smatch be used to count how many times a
> returned pointer is converted to int / bool before returning vs not
> converted?

I'm not super excited to write that code...  :/

> 
> I find Smatch interesting, especially when switching between projects
> frequently. Does it support changing the code like clang-format? To
> offload cognitive load to tools is usually good :).

No.  Coccinelle does that really well though.

regards,
dan carpenter