linux-kernel - Re: [PATCH 2/3] Fix: tracepoint: static call function vs data state mismatch (v2)

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] [day] [month] [year] [list]

Date:   Thu, 5 Aug 2021 15:42:54 -0400 (EDT)
From:   Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
To:     rostedt <rostedt@...dmis.org>
Cc:     Ingo Molnar <mingo@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        paulmck <paulmck@...nel.org>,
        Stefan Metzmacher <metze@...ba.org>,
        stable <stable@...r.kernel.org>,
        linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/3] Fix: tracepoint: static call function vs data state
 mismatch (v2)

----- On Aug 5, 2021, at 3:38 PM, rostedt rostedt@...dmis.org wrote:

> On Thu, 5 Aug 2021 15:15:43 -0400 (EDT)
> Mathieu Desnoyers <mathieu.desnoyers@...icios.com> wrote:
> 
>> ----- On Aug 5, 2021, at 2:56 PM, rostedt rostedt@...dmis.org wrote:
>> 
>> > Note, there shouldn't be a "(v2)" outside the "[PATCH ]" part.
>> > Otherwise it gets added into the git commit during "git am".
>> 
>> Out of curiosity, do you know any way to annotate my local commits to have the
>> [PATCH v2] tag automatically generated by git send-email ?
> 
> I pass -v2 to git send-email, and it adds the v2 for me.

OK, so you version the entire patch series in one go. It makes sense.

> 
>> > This is a big enough regression, I'll even add a Fixes tag to the next
>> > patch on the final sha1 of this patch! Such that this patch won't be
>> > backported without the next patch.
>> 
>> This makes sense. I still wanted to keep the two patches separate so we would
>> introduce the (slow) state machine in the first patch, and optimize for
>> speed in the second. My intent is to facilitate of small logical changes,
>> and make bisection more precise in the future if we introduce an issue
>> here.
> 
> I agree which is why I didn't ask you to fold them. The logic in this
> code was a big enough change, where I agree it should be kept separate.
> Unfortunately, it caused a huge performance regression :-(, but at the
> same time, fixed a correctness issue, which Thomas always says that
> correctness trumps performance.
> 
> But the compromise is to add a Fixes tag to the next patch and document
> why they are separated, but still required to act as "one". I'll add
> that commentary.

Perfect, thanks!

Mathieu

> 
> -- Steve
> 
>> 
>> Calling out more clearly how slow things become with this patch is indeed
>> important.
>> 
>> >   
>> >> 

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com