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From: Nam Cao <namcao@linutronix.de>
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To: Gabriele Monaco <gmonaco@redhat.com>, linux-kernel@vger.kernel.org,
 Steven Rostedt <rostedt@goodmis.org>, Gabriele Monaco
 <gmonaco@redhat.com>, linux-trace-kernel@vger.kernel.org
Cc: Wen Yang <wen.yang@linux.dev>
Subject: Re: [PATCH v3 07/13] rv: Add automatic cleanup handlers for
 per-task HA monitors
In-Reply-To: <20260530141652.58084-8-gmonaco@redhat.com>
References: <20260530141652.58084-1-gmonaco@redhat.com>
 <20260530141652.58084-8-gmonaco@redhat.com>
Date: Mon, 01 Jun 2026 09:39:51 +0200
Message-ID: <877boiyaig.fsf@yellow.woof>
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Gabriele Monaco <gmonaco@redhat.com> writes:
> @@ -123,12 +144,15 @@ static int ha_monitor_init(void)
>  
>  	ha_mon_initializing = true;
>  	ret = da_monitor_init();
> +	if (ret == 0)
> +		ha_monitor_enable_hook();
>  	ha_mon_initializing = false;
>  	return ret;
>  }

What if between da_monitor_init() and ha_monitor_enable_hook(), a task
exits while a timer is still active, and then the timer callback is invoked?

Extremely rare, but I think it can be fixed easily by reordering the two functions.

>  static void ha_monitor_destroy(void)
>  {
> +	ha_monitor_disable_hook();
>  	da_monitor_destroy();
>  }

Same here, there is small window between the two function calls.

Nam