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Date: Wed, 04 Nov 2015 09:45:43 +1100
From: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
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To: Frederic Barrat <fbarrat@linux.vnet.ibm.com>, imunsie@au1.ibm.com,
 linuxppc-dev@lists.ozlabs.org
CC: stable@vger.kernel.org
Subject: Re: [PATCH] cxl: Fix struct pid leak when attaching a process through
 kernel API
References: <1446553215-18273-1-git-send-email-fbarrat@linux.vnet.ibm.com>
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On 03/11/15 23:20, Frederic Barrat wrote:
> When the cxl driver creates a context, it stores the pid of the
> calling task, and mistakenly increments the reference count of the
> struct pid twice, once through get_task_pid(), once through
> get_pid(). The reference count is only decremented once on detach. As
> a result, a struct pid is leaked and it reduces the number of
> processes that can run simultaneously by one.
> The fix is to simply remove the call to get_pid().
>
> There is a separate patch for the user API, since it goes to
> different kernel versions.
>
> Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
> Cc: <stable@vger.kernel.org> # 4.3+

Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>

-- 
Andrew Donnellan              Software Engineer, OzLabs
andrew.donnellan@au1.ibm.com  Australia Development Lab, Canberra
+61 2 6201 8874 (work)        IBM Australia Limited