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Subject: Re: [PATCH 06/12] powerpc/module: Rework is_early_mcount_callsite()
To: Michael Ellerman <mpe@ellerman.id.au>, linuxppc-dev@ozlabs.org
References: <1456324115-21144-1-git-send-email-mpe@ellerman.id.au>
 <1456324115-21144-6-git-send-email-mpe@ellerman.id.au>
Cc: duwe@lst.de, linux-kernel@vger.kernel.org, rostedt@goodmis.org,
 kamalesh@linux.vnet.ibm.com, pmladek@suse.com, jeyu@redhat.com,
 jkosina@suse.cz, live-patching@vger.kernel.org, mbenes@suse.cz
From: Balbir Singh <bsingharora@gmail.com>
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Date: Thu, 25 Feb 2016 10:39:17 +1100
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On 25/02/16 01:28, Michael Ellerman wrote:
> is_early_mcount_callsite() needs to detect either the two instruction or
> the three instruction versions of the _mcount() sequence.
>
> But if we're running a kernel with the two instruction sequence, we need
> to be careful not to read instruction - 2, otherwise we might fall off
> the front of a page and cause an oops.
>
> While we're here convert to bool to make the return semantics clear.
>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> ---
>  arch/powerpc/kernel/module_64.c | 30 ++++++++++++++----------------
>  1 file changed, 14 insertions(+), 16 deletions(-)
>
> Squash.
>
>
Do we even need to do this anymore?

Balbir Singh.