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: <CANn89i+ntByi2709y10PN6cgri-b0EWxPSNXdu_Nf2nOvJ45FQ@mail.gmail.com>
Date:   Sun, 8 Oct 2023 09:00:29 +0200
From:   Eric Dumazet <edumazet@...gle.com>
To:     Christian Marangi <ansuelsmth@...il.com>
Cc:     Jakub Kicinski <kuba@...nel.org>, Jason Gunthorpe <jgg@...pe.ca>,
        Leon Romanovsky <leon@...nel.org>,
        Wolfgang Grandegger <wg@...ndegger.com>,
        Marc Kleine-Budde <mkl@...gutronix.de>,
        "David S. Miller" <davem@...emloft.net>,
        Paolo Abeni <pabeni@...hat.com>,
        Chris Snook <chris.snook@...il.com>,
        Raju Rangoju <rajur@...lsio.com>,
        Jeroen de Borst <jeroendb@...gle.com>,
        Praveen Kaligineedi <pkaligineedi@...gle.com>,
        Shailend Chand <shailend@...gle.com>,
        Douglas Miller <dougmill@...ux.ibm.com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Nicholas Piggin <npiggin@...il.com>,
        Christophe Leroy <christophe.leroy@...roup.eu>,
        Nick Child <nnac123@...ux.ibm.com>,
        Haren Myneni <haren@...ux.ibm.com>,
        Rick Lindsley <ricklind@...ux.ibm.com>,
        Dany Madden <danymadden@...ibm.com>,
        Thomas Falcon <tlfalcon@...ux.ibm.com>,
        Tariq Toukan <tariqt@...dia.com>,
        Alexandre Torgue <alexandre.torgue@...s.st.com>,
        Jose Abreu <joabreu@...opsys.com>,
        Maxime Coquelin <mcoquelin.stm32@...il.com>,
        Krzysztof Halasa <khalasa@...p.pl>,
        Kalle Valo <kvalo@...nel.org>,
        Jeff Johnson <quic_jjohnson@...cinc.com>,
        Gregory Greenman <gregory.greenman@...el.com>,
        Chandrashekar Devegowda <chandrashekar.devegowda@...el.com>,
        Intel Corporation <linuxwwan@...el.com>,
        Chiranjeevi Rapolu <chiranjeevi.rapolu@...ux.intel.com>,
        Liu Haijun <haijun.liu@...iatek.com>,
        M Chetan Kumar <m.chetan.kumar@...ux.intel.com>,
        Ricardo Martinez <ricardo.martinez@...ux.intel.com>,
        Loic Poulain <loic.poulain@...aro.org>,
        Sergey Ryazanov <ryazanov.s.a@...il.com>,
        Johannes Berg <johannes@...solutions.net>,
        Yuanjun Gong <ruc_gongyuanjun@....com>,
        Simon Horman <horms@...nel.org>, Rob Herring <robh@...nel.org>,
        Ziwei Xiao <ziweixiao@...gle.com>,
        Rushil Gupta <rushilg@...gle.com>,
        Coco Li <lixiaoyan@...gle.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Junfeng Guo <junfeng.guo@...el.com>,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>, Wei Fang <wei.fang@....com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>,
        Yuri Karpov <YKarpov@...ras.ru>,
        Zhengchao Shao <shaozhengchao@...wei.com>,
        Andrew Lunn <andrew@...n.ch>,
        Zheng Zengkai <zhengzengkai@...wei.com>,
        Lee Jones <lee@...nel.org>,
        Maximilian Luz <luzmaximilian@...il.com>,
        "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
        Dawei Li <set_pte_at@...look.com>,
        Anjaneyulu <pagadala.yesu.anjaneyulu@...el.com>,
        Benjamin Berg <benjamin.berg@...el.com>,
        linux-rdma@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-can@...r.kernel.org, netdev@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org,
        linux-stm32@...md-mailman.stormreply.com,
        linux-arm-kernel@...ts.infradead.org, ath10k@...ts.infradead.org,
        linux-wireless@...r.kernel.org
Subject: Re: [net-next PATCH v2 3/4] netdev: replace napi_reschedule with napi_schedule

On Fri, Oct 6, 2023 at 8:52 PM Christian Marangi <ansuelsmth@...il.com> wrote:
>
> On Thu, Oct 05, 2023 at 06:41:03PM +0200, Eric Dumazet wrote:
> > On Thu, Oct 5, 2023 at 6:32 PM Jakub Kicinski <kuba@...nel.org> wrote:
> > >
> > > On Thu, 5 Oct 2023 18:11:56 +0200 Eric Dumazet wrote:
> > > > OK, but I suspect some users of napi_reschedule() might not be race-free...
> > >
> > > What's the race you're thinking of?
> >
> > This sort of thing... the race is in fl_starving() though...
> >
> > diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c
> > b/drivers/net/ethernet/chelsio/cxgb4/sge.c
> > index 98dd78551d89..b5ff2e1a9975 100644
> > --- a/drivers/net/ethernet/chelsio/cxgb4/sge.c
> > +++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c
> > @@ -4261,7 +4261,7 @@ static void sge_rx_timer_cb(struct timer_list *t)
> >
> >                         if (fl_starving(adap, fl)) {
> >                                 rxq = container_of(fl, struct sge_eth_rxq, fl);
> > -                               if (napi_reschedule(&rxq->rspq.napi))
> > +                               if (napi_schedule(&rxq->rspq.napi))
> >                                         fl->starving++;
> >                                 else
> >                                         set_bit(id, s->starving_fl);
>
> Ehhh problem is that this is a simple rename so if any race is present,
> it's already there and not caused by this rename :(
>
> Don't know maybe this is out of scope and should be investigated with a
> bug report?
>
> Maybe this should be changed to prep/__schedule to prevent any kind of
> race? But doing so doesn't prevent any kind of ""starving""?
>

I gave a "Reviewed-by: Eric Dumazet <edumazet@...gle.com>", meaning
your patch was ok for me.

My remark was orthogonal, I am not asking you to act on it ;)

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ