[PATCH] arm: cacheflush: get rid of restarting block

From: vladimir.murzin@arm.com (Vladimir Murzin)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] arm: cacheflush: get rid of restarting block
Date: Thu, 27 Nov 2014 10:43:23 +0000	[thread overview]
Message-ID: <5477004B.5000100@arm.com> (raw)
In-Reply-To: <20141127100306.GA20649@arm.com>

On 27/11/14 10:03, Will Deacon wrote:
> On Thu, Nov 27, 2014 at 04:02:24AM +0000, Chanho Min wrote:
>>> -----Original Message-----
>>> From: Vladimir Murzin [mailto:vladimir.murzin at arm.com]
>>> Sent: Wednesday, November 26, 2014 12:19 AM
>>> To: linux-arm-kernel at lists.infradead.org; linux at arm.linux.org.uk
>>> Cc: chanho.min at lge.com; will.deacon at arm.com; stable at vger.kernel.org
>>> Subject: [PATCH] arm: cacheflush: get rid of restarting block
>>>
>>> We cannot restart cacheflush safely if a process provides user-defined
>>> signal handler and signal is pending. In this case -EINTR is returned
>>> and it is expected that process re-invokes syscall. However, there are
>>> a few problems with that:
>>>  * looks like nobody bothers checking return value from cacheflush
>>>  * but if it did, we don't provide the restart address for that, so the
>>>    process has to use the same range again
>>>  * ...and again, what might lead to looping forever
>>>
>>> So, remove cacheflush restarting code and terminate cache flushing
>>> as early as fatal signal is pending.
>>>
>>> Cc: stable at vger.kernel.org # 3.12+
>>> Reported-by: Chanho Min <chanho.min@lge.com>
>>> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
>>> Acked-by: Will Deacon <will.deacon@arm.com>
>>> ---
>>> Hi,
>>>
>>> There is my proposal for the problem reported in [1]. Since that
>>> thread has not been progressing much, I'm addressing the problem in
>>> separate patch.
>>>
>>> Comments?
>> Thanks, We hope this to be applied.
>
> Ok, good. In which case, can you put it into the patch system please,
> Vladimir?

Already in patch system as 8226/1.

Vladimir

>
> Will
>
>
>

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