Commit 108eae2d authored Jan 09, 2020 by Julien Thierry Committed by Will Deacon Jan 21, 2020

arm64: entry: Avoid empty alternatives entries



kernel_ventry will create alternative entries to potentially replace
0 instructions with 0 instructions for EL1 vectors. While this does not
cause an issue, it pointlessly takes up some bytes in the alternatives
section.

Do not generate such entries.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>

parent 98346023

arch/arm64/kernel/entry.S

+2 −2

Original line number	Diff line number	Diff line
		@@ -60,16 +60,16 @@
		.macro kernel_ventry, el, label, regsize = 64
		.align 7
		#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
		alternative_if ARM64_UNMAP_KERNEL_AT_EL0
		.if \el == 0
		alternative_if ARM64_UNMAP_KERNEL_AT_EL0
		.if \regsize == 64
		mrs x30, tpidrro_el0
		msr tpidrro_el0, xzr
		.else
		mov x30, xzr
		.endif
		.endif
		alternative_else_nop_endif
		.endif
		#endif

		sub sp, sp, #S_FRAME_SIZE

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