x86/asm/purgatory: Start using annotations

Purgatory used no annotations at all. So include linux/linkage.h and
annotate everything:

* code by SYM_CODE_*
* data by SYM_DATA_*

 [ bp: Fixup comment in gdt: ]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alexios Zavras <alexios.zavras@intel.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Enrico Weigelt <info@metux.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-arch@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191011115108.12392-16-jslaby@suse.cz

arch/x86/purgatory/entry64.S

@@ -8,13 +8,13 @@
  * This code has been taken from kexec-tools.
  */
 
+#include <linux/linkage.h>
+
 	.text
 	.balign 16
 	.code64
-	.globl entry64, entry64_regs
-
 
-entry64:
+SYM_CODE_START(entry64)
 	/* Setup a gdt that should be preserved */
 	lgdt gdt(%rip)
 
@@ -54,10 +54,11 @@ new_cs_exit:
 
 	/* Jump to the new code... */
 	jmpq	*rip(%rip)
+SYM_CODE_END(entry64)
 
 	.section ".rodata"
 	.balign 4
-entry64_regs:
+SYM_DATA_START(entry64_regs)
 rax:	.quad 0x0
 rcx:	.quad 0x0
 rdx:	.quad 0x0
@@ -75,13 +76,14 @@ r13:	.quad 0x0
 r14:	.quad 0x0
 r15:	.quad 0x0
 rip:	.quad 0x0
-	.size entry64_regs, . - entry64_regs
+SYM_DATA_END(entry64_regs)
 
 	/* GDT */
 	.section ".rodata"
 	.balign 16
-gdt:
-	/* 0x00 unusable segment
+SYM_DATA_START_LOCAL(gdt)
+	/*
+	 * 0x00 unusable segment
 	 * 0x08 unused
 	 * so use them as gdt ptr
 	 */
@@ -94,6 +96,8 @@ gdt:
 
 	/* 0x18 4GB flat data segment */
 	.word 0xFFFF, 0x0000, 0x9200, 0x00CF
-gdt_end:
-stack:	.quad   0, 0
-stack_init:
+SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end)
+
+SYM_DATA_START_LOCAL(stack)
+	.quad   0, 0
+SYM_DATA_END_LABEL(stack, SYM_L_LOCAL, stack_init)

arch/x86/purgatory/setup-x86_64.S

@@ -7,14 +7,14 @@
  *
  * This code has been taken from kexec-tools.
  */
+#include <linux/linkage.h>
 #include <asm/purgatory.h>
 
 	.text
-	.globl purgatory_start
 	.balign 16
-purgatory_start:
 	.code64
 
+SYM_CODE_START(purgatory_start)
 	/* Load a gdt so I know what the segment registers are */
 	lgdt	gdt(%rip)
 
@@ -32,10 +32,12 @@ purgatory_start:
 	/* Call the C code */
 	call purgatory
 	jmp	entry64
+SYM_CODE_END(purgatory_start)
 
 	.section ".rodata"
 	.balign 16
-gdt:	/* 0x00 unusable segment
+SYM_DATA_START_LOCAL(gdt)
+	/* 0x00 unusable segment
 	 * 0x08 unused
 	 * so use them as the gdt ptr
 	 */
@@ -48,10 +50,10 @@ gdt:	/* 0x00 unusable segment
 
 	/* 0x18 4GB flat data segment */
 	.word	0xFFFF, 0x0000, 0x9200, 0x00CF
-gdt_end:
+SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end)
 
 	.bss
 	.balign 4096
-lstack:
+SYM_DATA_START_LOCAL(lstack)
 	.skip 4096
-lstack_end:
+SYM_DATA_END_LABEL(lstack, SYM_L_LOCAL, lstack_end)

arch/x86/purgatory/stack.S

@@ -5,13 +5,14 @@
  * Copyright (C) 2014 Red Hat Inc.
  */
 
+#include <linux/linkage.h>
+
 	/* A stack for the loaded kernel.
 	 * Separate and in the data section so it can be prepopulated.
 	 */
 	.data
 	.balign 4096
-	.globl stack, stack_end
 
-stack:
+SYM_DATA_START(stack)
 	.skip 4096
-stack_end:
+SYM_DATA_END_LABEL(stack, SYM_L_GLOBAL, stack_end)