Subject: Re: [PATCH] module: set __jump_table alignment to 8
To: David Daney <david.daney@cavium.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Sachin Sant <sachinp@linux.vnet.ibm.com>, linux-kernel@vger.kernel.org
References: <20170301220453.4756-1-david.daney@cavium.com>
Cc: linux-mips@linux-mips.org, linuxppc-dev@lists.ozlabs.org,
        linux-arm-kernel@lists.infradead.org,
        Chris Metcalf <cmetcalf@mellanox.com>,
        Ralf Baechle <ralf@linux-mips.org>,
        Russell King <linux@armlinux.org.uk>, Rabin Vincent <rabin@rab.in>,
        Paul Mackerras <paulus@samba.org>, Anton Blanchard <anton@samba.org>,
        Ingo Molnar <mingo@kernel.org>, Zhigang Lu <zlu@ezchip.com>
From: Jason Baron <jbaron@akamai.com>
Message-ID: <7bc6b5af-85e0-5b06-f979-368b8b840a16@akamai.com>
Date: Thu, 2 Mar 2017 10:30:50 -0500
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101
 Thunderbird/45.7.0
MIME-Version: 1.0
In-Reply-To: <20170301220453.4756-1-david.daney@cavium.com>
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 728
Lines: 23

On 03/01/2017 05:04 PM, David Daney wrote:
> For powerpc the __jump_table section in modules is not aligned, this
> causes a WARN_ON() splat when loading a module containing a __jump_table.
>
> Strict alignment became necessary with commit 3821fd35b58d
> ("jump_label: Reduce the size of struct static_key"), currently in
> linux-next, which uses the two least significant bits of pointers to
> __jump_table elements.
>
> Fix by forcing __jump_table to 8, which is the same alignment used for
> this section in the kernel proper.
>
> Signed-off-by: David Daney <david.daney@cavium.com>
> Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
> ---

Looks good to me.

Reviewed-by: Jason Baron <jbaron@akamai.com>

Thanks,

-Jason