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Date: Thu, 16 Nov 2017 08:32:50 -0800
From: Sami Tolvanen <samitolvanen@google.com>
To: Will Deacon <will.deacon@arm.com>
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Subject: Re: [PATCH v2 08/18] arm64: don't disable ADR_PREL_PG_HI21* with
 ARM64_ERRATUM_843419
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On Thu, Nov 16, 2017 at 11:44:06AM +0000, Will Deacon wrote:
> Right, and this would also mean that we silently load vulnerable
> modules that are linked with either LD that doesn't support
> --fix-cortex-a53-843419 or simply wasn't passed.

You'll see a warning at least if the linker doesn't support the flag,
but yes, you're correct. In v1 of this patch set, LTO depended on this
erratum not being selected, but I changed it in v2 based on Ard's
suggestion.

I'm fine with not being able to use LTO on devices that are affected
by this erratum, so either option works for me. I can even change
this so the user must explicitly disable the erratum in order to use
LTO. Thoughts?

Sami