From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mark Rutland <mark.rutland@arm.com>
Subject: Re: [PATCH 2/3] KVM: arm64: Access CNTHCTL_EL2 bit fields correctly
 on VHE systems
Date: Fri, 13 Jan 2017 14:46:23 +0000
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Cc: Marc Zyngier <marc.zyngier@arm.com>, kvm@vger.kernel.org,
        Paolo Bonzini <pbonzini@redhat.com>,
        kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org
To: Christoffer Dall <christoffer.dall@linaro.org>
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On Fri, Jan 13, 2017 at 01:36:12PM +0100, Christoffer Dall wrote:
> On Fri, Jan 13, 2017 at 11:31:32AM +0000, Marc Zyngier wrote:

> Further, are we guaranteed that the static branch gets compiled into
> something that doesn't actually look at cpu_hwcap_keys, which is not
> mapped in hyp mode?

The fact that this might happen silently seems to be a larger problem.

Can we do something like the EFI stub, and ensure that (unintentional)
references to symbols outside of the hyp-stub will fail to link? That's
ensrue by some symbol mangling in drivers/firmware/efi/libstub/Makefile.

I think this may have come up before; I can't recall if there was some
reason that was problematic.

Thanks,
Mark.