Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH 1/2] powerpc: Allow flush_icache_range to work across
 ranges >4GB
To:     Alastair D'Silva <alastair@au1.ibm.com>
Cc:     stable@vger.kernel.org,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
References: <20190809004548.22445-1-alastair@au1.ibm.com>
 <a9bcc457-9f9b-7010-6796-fb263135f8bc@c-s.fr>
 <72a3fca157a508a9f1bc6ea20801b9227d788f1d.camel@au1.ibm.com>
From:   Christophe Leroy <christophe.leroy@c-s.fr>
Message-ID: <d481e068-5688-d507-b78c-c927ce7a70d3@c-s.fr>
Date:   Mon, 12 Aug 2019 07:41:25 +0200
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101
 Thunderbird/60.8.0
MIME-Version: 1.0
In-Reply-To: <72a3fca157a508a9f1bc6ea20801b9227d788f1d.camel@au1.ibm.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: fr
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


Le 12/08/2019 à 03:19, Alastair D'Silva a écrit :
> On Fri, 2019-08-09 at 10:59 +0200, Christophe Leroy wrote:
>>
>> Le 09/08/2019 à 02:45, Alastair D'Silva a écrit :
>>> From: Alastair D'Silva <alastair@d-silva.org>
>>>
>>> When calling flush_icache_range with a size >4GB, we were masking
>>> off the upper 32 bits, so we would incorrectly flush a range
>>> smaller
>>> than intended.
>>>
>>> This patch replaces the 32 bit shifts with 64 bit ones, so that
>>> the full size is accounted for.
>>>
>>> Heads-up for backporters: the old version of flush_dcache_range is
>>> subject to a similar bug (this has since been replaced with a C
>>> implementation).
>>
>> Can you submit a patch to stable, explaining this ?
>>
> 
> This patch was sent to stable too - or did you mean send another patch
> for the stable asm version of flush_dcache_range?
> 

Yes I meant a patch for your 'heads-up', in extenso a patch for fixing 
flush_dcache_range().

And for this patch, you put stable is copy of the mail, but for it to be 
taken into account it needs to also explicitely include a Cc: 
stable@vger.kernel.org in the commit message. I guess Michael will add 
it for this time.

Christophe