From: Ard Biesheuvel <ard.biesheu...@linaro.org>

Given that adr_this_cpu already requires a temp register in addition
to the destination register, tweak the instruction sequence so that sp
may be used as well.

This will simplify switching to per-cpu stacks in subsequent patches. While
this limits the range of adr_this_cpu, to +/-4GiB, we don't currently use
adr_this_cpu in modules, and this is not problematic for the main kernel image.

Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org>
[Mark: add more commit text]
Signed-off-by: Mark Rutland <mark.rutl...@arm.com>
Cc: Catalin Marinas <catalin.mari...@arm.com>
Cc: James Morse <james.mo...@arm.com>
Cc: Laura Abbott <labb...@redhat.com>
Cc: Will Deacon <will.dea...@arm.com>
---
 arch/arm64/include/asm/assembler.h | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/assembler.h 
b/arch/arm64/include/asm/assembler.h
index 610a420..2f2bd51 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -230,12 +230,18 @@
        .endm
 
        /*
-        * @dst: Result of per_cpu(sym, smp_processor_id())
+        * @dst: Result of per_cpu(sym, smp_processor_id()), can be SP for
+        *       non-module code
         * @sym: The name of the per-cpu variable
         * @tmp: scratch register
         */
        .macro adr_this_cpu, dst, sym, tmp
+#ifndef MODULE
+       adrp    \tmp, \sym
+       add     \dst, \tmp, #:lo12:\sym
+#else
        adr_l   \dst, \sym
+#endif
        mrs     \tmp, tpidr_el1
        add     \dst, \dst, \tmp
        .endm
-- 
1.9.1

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