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Subject: Re: [PATCH 4.9.257 1/1] futex: Fix OWNER_DEAD fixup
To:     Greg KH <gregkh@linuxfoundation.org>,
        Lee Jones <lee.jones@linaro.org>
CC:     <stable@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <judy.chenhui@huawei.com>, <zhangjinhao2@huawei.com>,
        <tglx@linutronix.de>
References: <20210222110542.3531596-1-zhengyejian1@huawei.com>
 <20210222110542.3531596-2-zhengyejian1@huawei.com>
 <20210222115424.GF376568@dell> <YDOec1kosGKKO80g@kroah.com>
From:   "Zhengyejian (Zetta)" <zhengyejian1@huawei.com>
Message-ID: <4f06340a-e027-f944-3248-2939639d5e07@huawei.com>
Date:   Mon, 22 Feb 2021 20:20:38 +0800
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On 2021/2/22 20:07, Greg KH wrote:
> On Mon, Feb 22, 2021 at 11:54:24AM +0000, Lee Jones wrote:
>> On Mon, 22 Feb 2021, Zheng Yejian wrote:
>>
>>> From: Peter Zijlstra <peterz@infradead.org>
>>>
>>> commit a97cb0e7b3f4c6297fd857055ae8e895f402f501 upstream.
>>>
>>> Both Geert and DaveJ reported that the recent futex commit:
>>>
>>>    c1e2f0eaf015 ("futex: Avoid violating the 10th rule of futex")
>>>
>>> introduced a problem with setting OWNER_DEAD. We set the bit on an
>>> uninitialized variable and then entirely optimize it away as a
>>> dead-store.
>>>
>>> Move the setting of the bit to where it is more useful.
>>>
>>> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
>>> Reported-by: Dave Jones <davej@codemonkey.org.uk>
>>> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
>>> Cc: Andrew Morton <akpm@linux-foundation.org>
>>> Cc: Linus Torvalds <torvalds@linux-foundation.org>
>>> Cc: Paul E. McKenney <paulmck@us.ibm.com>
>>> Cc: Peter Zijlstra <peterz@infradead.org>
>>> Cc: Thomas Gleixner <tglx@linutronix.de>
>>> Fixes: c1e2f0eaf015 ("futex: Avoid violating the 10th rule of futex")
>>> Link: http://lkml.kernel.org/r/20180122103947.GD2228@hirez.programming.kicks-ass.net
>>> Signed-off-by: Ingo Molnar <mingo@kernel.org>
>>> Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
>>> ---
>>>   kernel/futex.c | 7 +++----
>>>   1 file changed, 3 insertions(+), 4 deletions(-)
>>
>> Reviewed-by: Lee Jones <lee.jones@linaro.org>
> 
> This does not apply to the 4.9.y tree at all right now, are you all sure
> you got the backport correct?
> 
> confused,
> 
> greg k-h
> .
> 
I make the patch basing on 282aeb477a10 ("Linux 4.9.257").
Should I base on f0cf73f13b39 ("Linux 4.9.258-rc1")?