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Commit b03cc885 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Will Deacon
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arm64: kernel: replace early 64-bit literal loads with move-immediates 



When building a relocatable kernel, we currently rely on the fact that
early 64-bit literal loads need to be deferred to after the relocation
has been performed only if they involve symbol references, and not if
they involve assemble time constants. While this is not an unreasonable
assumption to make, it is better to switch to movk/movz sequences, since
these are guaranteed to be resolved at link time, simply because there are
no dynamic relocation types to describe them.

Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 30b5ba5c

arch/arm64/kernel/head.S

+4 −4
Original line number Diff line number Diff line
@@ -337,7 +337,7 @@ __create_page_tables: 
	cmp	x0, x6

	b.lo	1b



	ldr	x7, =SWAPPER_MM_MMUFLAGS

	mov	x7, SWAPPER_MM_MMUFLAGS



	/*

	 * Create the identity mapping.
@@ -393,7 +393,7 @@ __create_page_tables: 
	 * Map the kernel image (starting with PHYS_OFFSET).

	 */

	mov	x0, x26				// swapper_pg_dir

	ldr	x5, =KIMAGE_VADDR

	mov_q	x5, KIMAGE_VADDR

	add	x5, x5, x23			// add KASLR displacement

	create_pgd_entry x0, x5, x3, x6

	ldr	w6, =kernel_img_size
@@ -631,7 +631,7 @@ ENTRY(secondary_holding_pen) 
	bl	el2_setup			// Drop to EL1, w20=cpu_boot_mode

	bl	set_cpu_boot_mode_flag

	mrs	x0, mpidr_el1

	ldr     x1, =MPIDR_HWID_BITMASK

	mov_q	x1, MPIDR_HWID_BITMASK

	and	x0, x0, x1

	adr_l	x3, secondary_holding_pen_release

pen:	ldr	x4, [x3]
@@ -773,7 +773,7 @@ __primary_switch: 
	ldr	w9, =__rela_offset		// offset to reloc table

	ldr	w10, =__rela_size		// size of reloc table



	ldr	x11, =KIMAGE_VADDR		// default virtual offset

	mov_q	x11, KIMAGE_VADDR		// default virtual offset

	add	x11, x11, x23			// actual virtual offset

	add	x8, x8, x11			// __va(.dynsym)

	add	x9, x9, x11			// __va(.rela)