[PATCH v11 RESEND 9/9] arm64: armv8_deprecated: apply FEAT_LSUI for swpX emulation.

Marc Zyngier maz at kernel.org
Mon Dec 15 01:33:47 PST 2025


On Sun, 14 Dec 2025 11:22:48 +0000,
Yeoreum Yun <yeoreum.yun at arm.com> wrote:
> 
> Apply the FEAT_LSUI instruction to emulate the deprecated swpX
> instruction, so that toggling of the PSTATE.PAN bit can be removed when
> LSUI-related instructions are used.
> 
> Signed-off-by: Yeoreum Yun <yeoreum.yun at arm.com>

It really begs the question: what are the odds of ever seeing a CPU
that implements both LSUI and AArch32?

This seems extremely unlikely to me.

	M.

-- 
Without deviation from the norm, progress is not possible.



More information about the linux-arm-kernel mailing list