linux-kernel - Re: [PATCH v3 07/15] lockdep: Implement crossrelease feature

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 for Android: free password hash cracker in your pocket

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

Message-ID: <CANrsvRPQ=7ryYkYQpHUzK3Yzs_Yf-VH=1c6g=QnqqEP1WTJ5Xg@mail.gmail.com>
Date:   Wed, 14 Sep 2016 00:14:22 +0900
From:   Byungchul Park <max.byungchul.park@...il.com>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     Byungchul Park <byungchul.park@....com>,
        Ingo Molnar <mingo@...nel.org>, tglx@...utronix.de,
        walken@...gle.com, boqun.feng@...il.com, kirill@...temov.name,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        linux-mm@...ck.org, iamjoonsoo.kim@....com,
        akpm@...ux-foundation.org, npiggin@...il.com
Subject: Re: [PATCH v3 07/15] lockdep: Implement crossrelease feature

On Tue, Sep 13, 2016 at 7:05 PM, Peter Zijlstra <peterz@...radead.org> wrote:
> On Tue, Sep 13, 2016 at 06:45:06PM +0900, Byungchul Park wrote:
>> Crossrelease feature calls a lock 'crosslock' if it is releasable
>> in any context. For crosslock, all locks having been held in the
>> release context of the crosslock, until eventually the crosslock
>> will be released, have dependency with the crosslock.
>>
>> Using crossrelease feature, we can detect deadlock possibility even
>> for lock_page(), wait_for_complete() and so on.
>>
>
> Completely inadequate.
>
> Please explain how cross-release does what it does. Talk about lock
> graphs and such.

Hello,

Could you tell me about what you intend, in detail?
I'm now asking you since I really don't know it.

The reason I reworked on documentation was to
answer your requests like "explain mathematically",
"tell how it works with graph" and so on. Should I
do anything else? I really don't know it.

If I missed something, please let me know. Then I
can do whatever you want if it's necessary.

> I do not have time to reverse engineer this stuff.

Why don't you read the document in the last patch
first? The document is my answer for your requests
you asked in version 1 thread. Insufficient?