linux-kernel - Re: [PATCH AUTOSEL for 4.14 015/161] printk: Add console owner and waiter logic to load balance console writes

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]

Date:   Mon, 16 Apr 2018 15:38:16 -0400
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
Cc:     Sasha Levin <Alexander.Levin@...rosoft.com>,
        Pavel Machek <pavel@....cz>, Petr Mladek <pmladek@...e.com>,
        "stable@...r.kernel.org" <stable@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        Cong Wang <xiyou.wangcong@...il.com>,
        Dave Hansen <dave.hansen@...el.com>,
        Johannes Weiner <hannes@...xchg.org>,
        Mel Gorman <mgorman@...e.de>, Michal Hocko <mhocko@...nel.org>,
        Vlastimil Babka <vbabka@...e.cz>,
        Peter Zijlstra <peterz@...radead.org>, Jan Kara <jack@...e.cz>,
        Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
        Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>,
        Byungchul Park <byungchul.park@....com>,
        Tejun Heo <tj@...nel.org>, Greg KH <gregkh@...uxfoundation.org>
Subject: Re: [PATCH AUTOSEL for 4.14 015/161] printk: Add console owner and
 waiter logic to load balance console writes

On Mon, 16 Apr 2018 12:28:21 -0700
Linus Torvalds <torvalds@...ux-foundation.org> wrote:

> On Mon, Apr 16, 2018 at 12:24 PM, Steven Rostedt <rostedt@...dmis.org> wrote:
> >
> > Right, but the fix to the API was also trivial. I don't understand why
> > you are arguing with me. I agree with you. I'm talking about this
> > specific instance. Where a bug was fixed, and the API breakage was
> > another fix that needed to be backported.  
> 
> Fair enough. Were you there when the report of breakage came in?

No I wasn't.

> 
> Because *my* argument is that reverting something that causes problems
> is simply *never* the wrong answer.
> 
> If you know of the fix, fine. But clearly people DID NOT KNOW. So
> reverting was the right choice.

But I don't see in the git history that this was ever reverted. My reply
saying that "I hope it wasn't reverted", was a response for it being
reverted in stable, not mainline.  Considering that the original bug
would allow userspace to write zeros anywhere in memory, I would have
definitely worked on finding why the API breakage happened and fixing
it properly before putting such a large hole back into the kernel.

I'm assuming that may have been what happened because the commit was
never reverted in your tree, and if I was responsible for that code, I
would be up all night looking for an API fix to make sure the original
fix isn't reverted.

-- Steve