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Date:   Wed, 20 Jul 2022 10:47:18 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Daniel Bristot de Oliveira <bristot@kernel.org>
Cc:     Wim Van Sebroeck <wim@linux-watchdog.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Jonathan Corbet <corbet@lwn.net>,
        Ingo Molnar <mingo@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Will Deacon <will@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Marco Elver <elver@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Shuah Khan <skhan@linuxfoundation.org>,
        Gabriele Paoloni <gpaoloni@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Clark Williams <williams@redhat.com>,
        Tao Zhou <tao.zhou@linux.dev>,
        Randy Dunlap <rdunlap@infradead.org>,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-trace-devel@vger.kernel.org
Subject: Re: [PATCH V6 01/16] rv: Add Runtime Verification (RV) interface
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        <69bb4c369b4f6f12014eb9ca3c28b74e4378c007.1658244826.git.bristot@kernel.org>
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On Tue, 19 Jul 2022 19:27:06 +0200
Daniel Bristot de Oliveira <bristot@kernel.org> wrote:

> +/*
> + * Interface to read the enable/disable status of a monitor.
> + */
> +static ssize_t monitor_desc_read_data(struct file *filp, char __user *user_buf, size_t count,
> +				      loff_t *ppos)
> +{
> +	struct rv_monitor_def *mdef = filp->private_data;
> +	char buff[256];
> +
> +	memset(buff, 0, sizeof(buff));
> +
> +	mutex_lock(&rv_interface_lock);
> +	snprintf(buff, sizeof(buff), "%s\n", mdef->monitor->description);
> +	mutex_unlock(&rv_interface_lock);

What exactly is the mutex protecting here?

-- Steve

> +
> +	return simple_read_from_buffer(user_buf, count, ppos, buff, strlen(buff) + 1);
> +}
> +