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Date:   Wed, 12 Apr 2023 14:48:36 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Qi Zheng <zhengqi.arch@bytedance.com>
Cc:     Vlastimil Babka <vbabka@suse.cz>,
        "Zhang, Qiang1" <qiang1.zhang@intel.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        "42.hyeyoo@gmail.com" <42.hyeyoo@gmail.com>,
        "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "roman.gushchin@linux.dev" <roman.gushchin@linux.dev>,
        "iamjoonsoo.kim@lge.com" <iamjoonsoo.kim@lge.com>,
        "rientjes@google.com" <rientjes@google.com>,
        "penberg@kernel.org" <penberg@kernel.org>,
        "cl@linux.com" <cl@linux.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Zhao Gongyi <zhaogongyi@bytedance.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        RCU <rcu@vger.kernel.org>,
        "Paul E . McKenney" <paulmck@kernel.org>
Subject: Re: [PATCH] mm: slub: annotate kmem_cache_node->list_lock as
 raw_spinlock
Message-ID: <20230412124836.GF628377@hirez.programming.kicks-ass.net>
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On Wed, Apr 12, 2023 at 03:30:20PM +0800, Qi Zheng wrote:
> Maybe we should make CONFIG_PROVE_RAW_LOCK_NESTING depend on
> CONFIG_PREEMPT_RT:
> 
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index f0d5b82e478d..257b170aacb6 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -1262,6 +1262,7 @@ config PROVE_LOCKING
>  config PROVE_RAW_LOCK_NESTING
>         bool "Enable raw_spinlock - spinlock nesting checks"
>         depends on PROVE_LOCKING
> +       depends on PREEMPT_RT
>         default n
>         help
>          Enable the raw_spinlock vs. spinlock nesting checks which ensure

No, very much not. The idea is that we want to work towards having this
always enabled (when PROVE_LOCKING) to ensure code gets and stays
PREEMPT_RT clean.