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From: Michael Ellerman <mpe@ellerman.id.au>
To: Frederic Barrat <fbarrat@linux.vnet.ibm.com>,
	imunsie@au1.ibm.com, linuxppc-dev@lists.ozlabs.org
Cc: stable@vger.kernel.org
Subject: Re: cxl: Fix struct pid leak when attaching a process through user API
Date: Tue, 26 Jan 2016 14:11:02 +1100 (AEDT)	[thread overview]
Message-ID: <20160126031102.1CE27140317@ozlabs.org> (raw)
In-Reply-To: <1446552832-17592-1-git-send-email-fbarrat@linux.vnet.ibm.com>

On Tue, 2015-03-11 at 12:13:52 UTC, 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 kernel API, since it goes to
> different kernel versions.
> 
> Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
> Cc: <stable@vger.kernel.org> # 3.18+
> Acked-by: Ian Munsie <imunsie@au1.ibm.com>
> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>

This no longer applies, since we merged 7b8ad495d592 ("cxl: Fix DSI misses when
the context owning task exits").

Please resend if it's still applicable.

cheers

  parent reply	other threads:[~2016-01-26  3:11 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-03 12:13 [PATCH] cxl: Fix struct pid leak when attaching a process through user API Frederic Barrat
2015-11-03 22:25 ` Ian Munsie
2015-11-03 22:45 ` Andrew Donnellan
2016-01-26  3:11 ` Michael Ellerman [this message]
2016-01-26  8:16   ` Frederic Barrat

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