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From: Sasha Levin <Alexander.Levin@microsoft.com>
Subject: Re: [PATCH AUTOSEL for 4.14 015/161] printk: Add console owner and
 waiter logic to load balance console writes
Date: Mon, 16 Apr 2018 16:45:16 +0000
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To: Pavel Machek <pavel@ucw.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>, Steven Rostedt <rostedt@goodmis.org>, Petr Mladek <pmladek@suse.com>, "stable@vger.kernel.org" <stable@vger.kernel.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "akpm@linux-foundation.org" <akpm@linux-foundation.org>, "linux-mm@kvack.org" <linux-mm@kvack.org>, Cong Wang <xiyou.wangcong@gmail.com>, Dave Hansen <dave.hansen@intel.com>, Johannes Weiner <hannes@cmpxchg.org>, Mel Gorman <mgorman@suse.de>, Michal Hocko <mhocko@kernel.org>, Vlastimil Babka <vbabka@suse.cz>, Peter Zijlstra <peterz@infradead.org>, Jan Kara <jack@suse.cz>, Mathieu Desnoyers <mathieu.desnoyers@efficios.com>, Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>, Byungchul Park <byungchul.park@lge.com>, Tejun Heo <tj@kernel.org>

On Mon, Apr 16, 2018 at 06:42:30PM +0200, Pavel Machek wrote:
>On Mon 2018-04-16 16:39:20, Sasha Levin wrote:
>> On Mon, Apr 16, 2018 at 06:28:50PM +0200, Pavel Machek wrote:
>> >
>> >> >> Is there a reason not to take LED fixes if they fix a bug and don'=
t
>> >> >> cause a regression? Sure, we can draw some arbitrary line, maybe
>> >> >> designate some subsystems that are more "important" than others, b=
ut
>> >> >> what's the point?
>> >> >
>> >> >There's a tradeoff.
>> >> >
>> >> >You want to fix serious bugs in stable, and you really don't want
>> >> >regressions in stable. And ... stable not having 1000s of patches
>> >> >would be nice, too.
>> >>
>> >> I don't think we should use a number cap here, but rather look at the
>> >> regression rate: how many patches broke something?
>> >>
>> >> Since the rate we're seeing now with AUTOSEL is similar to what we we=
re
>> >> seeing before AUTOSEL, what's the problem it's causing?
>> >
>> >Regression rate should not be the only criteria.
>> >
>> >More patches mean bigger chance customer's patches will have a
>> >conflict with something in -stable, for example.
>>
>> Out of tree patches can't be a consideration here. There are no
>> guarantees for out of tree code, ever.
>
>Out of tree code is not consideration for mainline, agreed. Stable
>should be different.

This is a discussion we could have with in right forum, but FYI stable
doesn't even guarantee KABI compatibility between minor versions at this
point.