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Date:   Thu, 31 Mar 2022 19:51:13 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Youquan Song <youquan.song@linux.intel.com>
Cc:     Tony Luck <tony.luck@intel.com>, Borislav Petkov <bp@alien8.de>,
        Josh Poimboeuf <jpoimboe@redhat.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, Zhiquan Li <zhiquan1.li@intel.com>,
        Youquan Song <youquan.song@intel.com>
Subject: Re: [PATCH] x86/uaccess: restore get_user exception type to
 EX_TYPE_UACCESS
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References: <20220328201748.1864491-1-tony.luck@intel.com>
 <20220330123205.GL8939@worktop.programming.kicks-ass.net>
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On Thu, Mar 31, 2022 at 07:31:25PM +0800, Youquan Song wrote:
> > Did you do your testing on RHEL or something daft like that?
> Tested on RHEL8.x

Right; the home of obsolete software.. :-)

> > Something like the below can also work, I suppose. But please, add
> > coherent comments to the extable code with useful references to the MCE
> > code that does this abuse.
> Here is the full fix patch depending on your suggestion. Thanks a lot!

Did you verify this was indeed the only UACCESS I lost?

I'm also failing to spot a comment making extable users aware of this
abuse.