Commit 112f3bab authored by Will Deacon's avatar Will Deacon Committed by Marc Zyngier
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KVM: arm64: Extend comment in has_vhe() 



has_vhe() expands to a compile-time constant when evaluated from the VHE
or nVHE code, alternatively checking a static key when called from
elsewhere in the kernel. On face value, this looks like a case of
premature optimization, but in fact this allows symbol references on
VHE-specific code paths to be dropped from the nVHE object.

Expand the comment in has_vhe() to make this clearer, hopefully
discouraging anybody from simplifying the code.

Cc: David Brazdil <dbrazdil@google.com>
Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
Signed-off-by: default avatarWill Deacon <will@kernel.org>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220609121223.2551-5-will@kernel.org
parent cde5042a

arch/arm64/include/asm/virt.h

+3 −0
Original line number Diff line number Diff line
@@ -113,6 +113,9 @@ static __always_inline bool has_vhe(void) 
	/*

	 * Code only run in VHE/NVHE hyp context can assume VHE is present or

	 * absent. Otherwise fall back to caps.

	 * This allows the compiler to discard VHE-specific code from the

	 * nVHE object, reducing the number of external symbol references

	 * needed to link.

	 */

	if (is_vhe_hyp_code())

		return true;