Date:   Tue, 14 Dec 2021 16:55:00 +1100
From:   Balbir Singh <bsingharora@gmail.com>
To:     Leo Yan <leo.yan@linaro.org>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Leon Romanovsky <leon@kernel.org>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Mike Leach <mike.leach@linaro.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jan Harkes <jaharkes@cs.cmu.edu>, coda@cs.cmu.edu,
        Paul Moore <paul@paul-moore.com>,
        Eric Paris <eparis@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, coresight@lists.linaro.org,
        linux-arm-kernel@lists.infradead.org, codalist@coda.cs.cmu.edu,
        linux-audit@redhat.com
Subject: Re: [PATCH v2 2/7] coresight: etm3x: Use task_is_in_init_pid_ns()
Message-ID: <YbgxtIXwx7TZR88Y@balbir-desktop>
References: <20211208083320.472503-1-leo.yan@linaro.org>
 <20211208083320.472503-3-leo.yan@linaro.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20211208083320.472503-3-leo.yan@linaro.org>
Precedence: bulk

On Wed, Dec 08, 2021 at 04:33:15PM +0800, Leo Yan wrote:
> This patch replaces open code with task_is_in_init_pid_ns() to check if
> a task is in root PID namespace.
> 
> Signed-off-by: Leo Yan <leo.yan@linaro.org>
> ---
>  drivers/hwtracing/coresight/coresight-etm3x-sysfs.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
> index e8c7649f123e..ff76cb56b727 100644
> --- a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
> +++ b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
> @@ -1030,7 +1030,7 @@ static ssize_t ctxid_pid_show(struct device *dev,
>  	 * Don't use contextID tracing if coming from a PID namespace.  See
>  	 * comment in ctxid_pid_store().
>  	 */
> -	if (task_active_pid_ns(current) != &init_pid_ns)
> +	if (!task_is_in_init_pid_ns(current))
>  		return -EINVAL;
>  
>  	spin_lock(&drvdata->spinlock);
> @@ -1058,7 +1058,7 @@ static ssize_t ctxid_pid_store(struct device *dev,
>  	 * As such refuse to use the feature if @current is not in the initial
>  	 * PID namespace.
>  	 */
> -	if (task_active_pid_ns(current) != &init_pid_ns)
> +	if (!task_is_in_init_pid_ns(current))
>  		return -EINVAL;
>  
>  	ret = kstrtoul(buf, 16, &pid);
> @@ -1084,7 +1084,7 @@ static ssize_t ctxid_mask_show(struct device *dev,
>  	 * Don't use contextID tracing if coming from a PID namespace.  See
>  	 * comment in ctxid_pid_store().
>  	 */
> -	if (task_active_pid_ns(current) != &init_pid_ns)
> +	if (!task_is_in_init_pid_ns(current))
>  		return -EINVAL;
>  
>  	val = config->ctxid_mask;
> @@ -1104,7 +1104,7 @@ static ssize_t ctxid_mask_store(struct device *dev,
>  	 * Don't use contextID tracing if coming from a PID namespace.  See
>  	 * comment in ctxid_pid_store().
>  	 */
> -	if (task_active_pid_ns(current) != &init_pid_ns)
> +	if (!task_is_in_init_pid_ns(current))
>  		return -EINVAL;
>  
>  	ret = kstrtoul(buf, 16, &val);
> -- 
> 2.25.1
>

Acked-by: Balbir Singh <bsingharora@gmail.com>