linux-kernel - [stable:PATCH v4.9.309 31/43] arm64: entry: Move trampoline macros out of ifdef'd section

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Message-Id: <20220406164546.1888528-31-james.morse@arm.com>
Date:   Wed,  6 Apr 2022 17:45:34 +0100
From:   James Morse <james.morse@....com>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     James Morse <james.morse@....com>,
        Catalin Marinas <catalin.marinas@....com>
Subject: [stable:PATCH v4.9.309 31/43] arm64: entry: Move trampoline macros out of ifdef'd section

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@...linux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@....com>
Signed-off-by: James Morse <james.morse@....com>
---
 arch/arm64/kernel/entry.S | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 114922c1c3e3..9132400d6a9d 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -896,12 +896,7 @@ __ni_sys_trace:
 
 	.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
 	sub	\tmp, \tmp, #SWAPPER_DIR_SIZE
@@ -980,6 +975,11 @@ __ni_sys_trace:
 	.endr
 	.endm
 
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+/*
+ * Exception vectors trampoline.
+ */
+	.pushsection ".entry.tramp.text", "ax"
 	.align	11
 ENTRY(tramp_vectors)
 	generate_tramp_vector
-- 
2.30.2