netdev - Re: Problems with mvneta

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: <CAPv3WKchs0gFsBmOzvpBL61HyS9+wWPk9miKB-=tmPF25xBC-A@mail.gmail.com>
Date:   Wed, 1 Nov 2017 09:10:18 +0100
From:   Marcin Wojtas <mw@...ihalf.com>
To:     Thomas Petazzoni <thomas.petazzoni@...e-electrons.com>
Cc:     Simon Guinot <simon.guinot@...uanux.org>,
        Sven Müller <musv@....de>,
        Andreas Tobler <andreas.tobler@...udguard.ch>,
        Grégory Clement 
        <gregory.clement@...e-electrons.com>,
        Antoine Ténart <antoine.tenart@...e-electrons.com>,
        netdev <netdev@...r.kernel.org>
Subject: Re: Problems with mvneta

Hi Thomas,

2017-10-31 21:23 GMT+01:00 Thomas Petazzoni
<thomas.petazzoni@...e-electrons.com>:
> Hello,
>
> On Tue, 31 Oct 2017 18:09:38 +0100, Simon Guinot wrote:
>
>> > On Tue, 31 Oct 2017 15:23:22 +0100, Sven Müller wrote:
>> > > After quite a long time of trying to reproduce the issue without any success I got 3 network crashes today. And all errors occurred with a kernel including the patch:
>> > >
>> > > 2a90f7e1d5d04e4f1060268e0b55a2c702bbd67a
>> > >
>> > > At least according to Andreas' and my problems we can exclude the 6ad2 patch as the source of the errors.
>> >
>> > Simon, 2a90f7e1d5d04e4f1060268e0b55a2c702bbd67a is your commit, adding
>> > xmit_more support, and a number of people are reporting stability
>> > issues with this patch applied.
>>
>> I wrote an earlier version of this patch. But I think this commit has
>> been modified by the submitter Marcin Wojtas because I don't remember
>> anything about the maximum number of descriptors allowed to be flush.
>>
>> >
>> > Do you think you will have some time to look into this ?
>>
>> No I don't have time to look into that.
>>
>> But after a quick look, I wonder what is happening if
>> "txq->pending + frags > MVNETA_TXQ_DEC_SENT_MASK" ? Because IIUC
>> mvneta_txq_pend_desc_add() is called anyway. And according to the
>> comment inside the function, it assumes there is less than 255
>> descriptors to send... It looks suspect.
>
> Thanks for the feedback. Marcin, do you remember this xmit_more patch?
>

Yes I do. It seems pretty simple and didn't show any issues durin very
long stress tests. I will check the mvneta_tx() routine if there's
anything suspicios/missed.

Marcin