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Date:   Mon, 29 Aug 2022 09:14:32 +0200
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Subject: Re: [PATCH modules-next] module: Add debugfs interface to view
 unloaded tainted modules
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To:     Aaron Tomlin <atomlin@redhat.com>, mcgrof@kernel.org
Cc:     christophe.leroy@csgroup.eu, linux-kernel@vger.kernel.org,
        linux-modules@vger.kernel.org, atomlin@atomlin.com
References: <20220823193225.2072649-1-atomlin@redhat.com>
From:   Petr Pavlu <petr.pavlu@suse.com>
In-Reply-To: <20220823193225.2072649-1-atomlin@redhat.com>
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On 8/23/22 21:32, Aaron Tomlin wrote:
> [...]
> @@ -59,3 +60,68 @@ void print_unloaded_tainted_modules(void)
>  		}
>  	}
>  }
> +
> +#ifdef CONFIG_DEBUG_FS
> +static void *unloaded_tainted_modules_seq_start(struct seq_file *m, loff_t *pos)
> +{
> +	mutex_lock(&module_mutex);
> +	return seq_list_start_rcu(&unloaded_tainted_modules, *pos);
> +}

unloaded_tainted_modules looks to be a proper RCU list which makes me think
this reader could use just rcu_read_lock() instead of
mutex_lock(&module_mutex)?

Thanks,
Petr