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Subject: Re: 3.5+: yaboot, Invalid memory access
From: Steven Rostedt <rostedt@goodmis.org>
To: Michael Ellerman <michael@ellerman.id.au>
Date: Tue, 04 Sep 2012 10:27:20 -0400
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On Tue, 2012-09-04 at 16:51 +1000, Michael Ellerman wrote:

> My guess would be we're calling that quite early and the __put_user()
> check is getting confused and failing. That means we'll have left some
> code unpatched, which then fails.
> 
> Can you try with the patch applied, but instead of returning if the
> __put_user() fails, just continue on anyway.
> 
> That will isolate if it's something in the __put_user() (I doubt it), or
> just that the __put_user() is failing and leaving the code unpatched.

As a test case, continuing on error is fine, but I would not recommend
that as a fix. If it fails, but still does the patch, that could be
harmful, and confusing of a result.

Need to figure out why put_user is failing.

-- Steve