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Date: Thu, 29 Jun 2017 14:19:16 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
Subject: [bug report] percpu: add tracepoint support for percpu memory
Message-ID: <20170629110954.uz6he7x25bg4n3pp@mwanda>
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Hello Dennis Zhou,

This is a semi-automatic email about new static checker warnings.

The patch df95e795a722: "percpu: add tracepoint support for percpu
memory" from Jun 19, 2017, leads to the following Smatch complaint:

    mm/percpu-km.c:88 pcpu_destroy_chunk()
    warn: variable dereferenced before check 'chunk' (see line 86)

mm/percpu-km.c
    85		pcpu_stats_chunk_dealloc();
    86		trace_percpu_destroy_chunk(chunk->base_addr);
                                           ^^^^^^^^^^^^^^^^
There should probably be a NULL check here?

    87	
    88		if (chunk && chunk->data)
    89			__free_pages(chunk->data, order_base_2(nr_pages));
    90		pcpu_free_chunk(chunk);

regards,
dan carpenter

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Date: Thu, 29 Jun 2017 10:56:26 -0400
From: Dennis Zhou <dennisz@fb.com>
Subject: [PATCH 1/1] percpu: fix static checker warnings in pcpu_destroy_chunk
Message-ID: <20170629145625.GA79969@dennisz-mbp>
References: <20170629110954.uz6he7x25bg4n3pp@mwanda>
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To: Tejun Heo <tj@kernel.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>, linux-mm@kvack.org


From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Thu, 29 Jun 2017 11:24:13 -0400
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH 1/1] percpu: fix static checker warnings in
 pcpu_destroy_chunk
Message-ID: <20170629152413.GA9745@htj.duckdns.org>
References: <20170629110954.uz6he7x25bg4n3pp@mwanda>
 <20170629145625.GA79969@dennisz-mbp>
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To: Dennis Zhou <dennisz@fb.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>, linux-mm@kvack.org

On Thu, Jun 29, 2017 at 10:56:26AM -0400, Dennis Zhou wrote:
> From 5021b97f4026334d2c8dfad80797dd1028cddd73 Mon Sep 17 00:00:00 2001
> From: Dennis Zhou <dennisz@fb.com>
> Date: Thu, 29 Jun 2017 07:11:41 -0700
> 
> Add NULL check in pcpu_destroy_chunk to correct static checker warnings.
> 
> Signed-off-by: Dennis Zhou <dennisz@fb.com>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

Applied to percpu/for-4.13.

Thanks.

-- 
tejun

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