arm64: entry: Move trampoline macros out of ifdef'd section

stable inclusion
from stable-v4.19.236
commit f689fa53bb944873f75fe1584f446cae1aabd2c1
category: bugfix
bugzilla: 186460, https://gitee.com/src-openeuler/kernel/issues/I53MHA
CVE: CVE-2022-23960

--------------------------------

commit 13d7a083 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: NRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NJames Morse <james.morse@arm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jiahao <chenjiahao16@huawei.com>
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Reviewed-by: NLiao Chang <liaochang1@huawei.com>
Signed-off-by: NYongqiang Liu <liuyongqiang13@huawei.com>

arch/arm64/kernel/entry.S

@@ -1033,12 +1033,7 @@ 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)
@@ -1129,6 +1124,11 @@ alternative_insn isb, nop, ARM64_WORKAROUND_QCOM_FALKOR_E1003
 	.endr
 	.endm
 
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+/*
+ * Exception vectors trampoline.
+ */
+	.pushsection ".entry.tramp.text", "ax"
 	.align	11
 ENTRY(tramp_vectors)
 	generate_tramp_vector