[PATCH 4.19 32/57] arm64: entry: Move trampoline macros out of ifdefd section

From: Greg Kroah-Hartman
Date: Mon Mar 21 2022 - 10:00:07 EST


From: James Morse <james.morse@xxxxxxx>

commit 13d7a08352a83ef2252aeb464a5e08dfc06b5dfd upstream.

The macros for building the kpti trampoline are all behind
CONFIG_UNMAP_KERNEL_AT_EL0, and in a region that outputs to the
.entry.tramp.text section.

Move the macros out so they can be used to generate other kinds of
trampoline. Only the symbols need to be guarded by
CONFIG_UNMAP_KERNEL_AT_EL0 and appear in the .entry.tramp.text section.

Reviewed-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm64/kernel/entry.S | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -933,12 +933,7 @@ ENDPROC(el0_svc)

.popsection // .entry.text

-#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-/*
- * Exception vectors trampoline.
- */
- .pushsection ".entry.tramp.text", "ax"
-
+ // Move from tramp_pg_dir to swapper_pg_dir
.macro tramp_map_kernel, tmp
mrs \tmp, ttbr1_el1
add \tmp, \tmp, #(PAGE_SIZE + RESERVED_TTBR0_SIZE)
@@ -1029,6 +1024,11 @@ alternative_insn isb, nop, ARM64_WORKARO
.endr
.endm

+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+/*
+ * Exception vectors trampoline.
+ */
+ .pushsection ".entry.tramp.text", "ax"
.align 11
ENTRY(tramp_vectors)
generate_tramp_vector