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Date:   Wed, 18 Mar 2020 11:32:17 +0000
From:   Mark Brown <broonie@kernel.org>
To:     Will Deacon <will@kernel.org>
Cc:     Mark Rutland <mark.rutland@arm.com>,
        Hongbo Yao <yaohongbo@huawei.com>,
        linux-kernel@vger.kernel.org, catalin.marinas@arm.com,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [RFC PATCH] arm64: fix the missing ktpi= cmdline check in
 arm64_kernel_unmapped_at_el0()
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On Tue, Mar 17, 2020 at 09:01:54PM +0000, Will Deacon wrote:
> On Tue, Mar 17, 2020 at 04:36:38PM +0000, Mark Brown wrote:

> > I'd need to go back and retest to confirm but it looks like always had
> > the issue that we'd install some nG mappings early even with KPTI
> > disabled on the command line so your change is just restoring the
> > previous behaviour and we're no worse than we were before.

> Urgh, this code brings back really bad memories :( :( :(

Tell me about it.

> So I've hacked the following, which appears to work but damn I'd like
> somebody else to look at this. I also have a nagging feeling that you
> implemented it like this at some point, but we tried to consolidate things
> during review.

> Thoughts?

I don't think I did *exactly* this but it's familiar yeah.  It looks
sensible and I can't think of any problems but that doesn't mean there
aren't any.

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