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Date:   Thu, 1 Nov 2018 10:17:40 +0100 (CET)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Daniel Wagner <wagi@monom.org>
cc:     stable@vger.kernel.org, linux-kernel@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Daniel Wagner <daniel.wagner@siemens.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v4.4] x86/kconfig: Fall back to ticket spinlocks
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References: <20181031081458.13996-1-wagi@monom.org>
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On Wed, 31 Oct 2018, Daniel Wagner wrote:
> Backporting all qspinlock related patches is very likely to introduce
> regressions on v4.4. Therefore, the recommended solution by Peter and
> Thomas is to drop back to ticket spinlocks for v4.4.
> 
> Link :https://lkml.kernel.org/r/20180921120226.6xjgr4oiho22ex75@linutronix.de
> Link: https://lkml.kernel.org/r/20180926110117.405325143@infradead.org
> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>

Acked-by: Thomas Gleixner <tglx@linutronix.de>

> Signed-off-by: Daniel Wagner <daniel.wagner@siemens.com>
> ---
> 
> Thomas suggest following plan for fixing the issues on the varous
> stable trees:
> 
>    4.4:  Trivial by switching back to ticket locks.
> 
>    4.9:  Decide whether bringing back ticket locks or backporting all qrlock
>    	 fixes. Sebastian has done the latter already and it's probably the
>    	 right solution
> 
>    4.14:
>    4.18: Backporting the qrlock fixes
> 
>    4.19: Either the fix ends up in 4.19 final or it needs to be backported

Looks about right. Sebastian, can you please provide the 4.9 backport as a
patch series?

Thanks,

	tglx