[PATCH v2 08/29] ARM: head: use PC-relative insn sequence for __smp_alt
From: Nicolas Pitre <hidden>
Date: 2017-09-04 16:19:10
On Sun, 3 Sep 2017, Ard Biesheuvel wrote:
Replace the open coded PC relative offset calculations with a pair of adr_l invocations. This ensures these quantities are invariant under runtime relocation.
You probably should add that this patch must be applied on top of "ARM: kernel: use relative references for UP/SMP alternatives" because of the expected r3 value prior to that patch. Acked-by: Nicolas Pitre <redacted>
quoted hunk ↗ jump to hunk
Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Ard Biesheuvel <redacted> --- arch/arm/kernel/head.S | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-)diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index ec22f42fd8bb..db6b823f20a4 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S@@ -523,19 +523,11 @@ ARM_BE8(rev r0, r0) @ byteswap if big endian retne lr __fixup_smp_on_up: - adr r0, 1f - ldmia r0, {r3 - r5} - sub r3, r0, r3 - add r4, r4, r3 - add r5, r5, r3 + adr_l r4, __smpalt_begin + adr_l r5, __smpalt_end b __do_fixup_smp_on_up ENDPROC(__fixup_smp) - .align -1: .word . - .word __smpalt_begin - .word __smpalt_end - .pushsection .data .globl smp_on_up smp_on_up:-- 2.11.0