Commit aca282ab authored by Josh Poimboeuf's avatar Josh Poimboeuf
Browse files

x86/asm: Annotate special section entries 



In preparation for the objtool klp diff subcommand, add annotations for
special section entries.  This will enable objtool to determine the size
and location of the entries and to extract them when needed.

Acked-by: default avatarPetr Mladek <pmladek@suse.com>
Tested-by: default avatarJoe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@kernel.org>
parent 58f36a57

arch/x86/include/asm/alternative.h

+4 −0
Original line number Diff line number Diff line
@@ -198,6 +198,7 @@ static inline int alternatives_text_reserved(void *start, void *end) 


#define ALTINSTR_ENTRY(ft_flags)					      \

	".pushsection .altinstructions,\"a\"\n"				      \

	ANNOTATE_DATA_SPECIAL						      \

	" .long 771b - .\n"				/* label           */ \

	" .long 774f - .\n"				/* new instruction */ \

	" .4byte " __stringify(ft_flags) "\n"		/* feature + flags */ \
@@ -207,6 +208,7 @@ static inline int alternatives_text_reserved(void *start, void *end) 


#define ALTINSTR_REPLACEMENT(newinstr)		/* replacement */	\

	".pushsection .altinstr_replacement, \"ax\"\n"			\

	ANNOTATE_DATA_SPECIAL						\

	"# ALT: replacement\n"						\

	"774:\n\t" newinstr "\n775:\n"					\

	".popsection\n"
@@ -337,6 +339,7 @@ void nop_func(void); 
 * instruction. See apply_alternatives().

 */

.macro altinstr_entry orig alt ft_flags orig_len alt_len

	ANNOTATE_DATA_SPECIAL

	.long \orig - .

	.long \alt - .

	.4byte \ft_flags
@@ -365,6 +368,7 @@ void nop_func(void); 
	.popsection ;							\

	.pushsection .altinstr_replacement,"ax"	;			\

743:									\

	ANNOTATE_DATA_SPECIAL ;						\

	newinst	;							\

744:									\

	.popsection ;

arch/x86/include/asm/asm.h

+5 −0
Original line number Diff line number Diff line
@@ -2,6 +2,8 @@ 
#ifndef _ASM_X86_ASM_H

#define _ASM_X86_ASM_H



#include <linux/annotate.h>



#ifdef __ASSEMBLER__

# define __ASM_FORM(x, ...)		x,## __VA_ARGS__

# define __ASM_FORM_RAW(x, ...)		x,## __VA_ARGS__
@@ -132,6 +134,7 @@ static __always_inline __pure void *rip_rel_ptr(void *p) 
# define _ASM_EXTABLE_TYPE(from, to, type)			\

	.pushsection "__ex_table","a" ;				\

	.balign 4 ;						\

	ANNOTATE_DATA_SPECIAL ;					\

	.long (from) - . ;					\

	.long (to) - . ;					\

	.long type ;						\
@@ -179,6 +182,7 @@ static __always_inline __pure void *rip_rel_ptr(void *p) 
# define _ASM_EXTABLE_TYPE(from, to, type)			\

	" .pushsection \"__ex_table\",\"a\"\n"			\

	" .balign 4\n"						\

	ANNOTATE_DATA_SPECIAL					\

	" .long (" #from ") - .\n"				\

	" .long (" #to ") - .\n"				\

	" .long " __stringify(type) " \n"			\
@@ -187,6 +191,7 @@ static __always_inline __pure void *rip_rel_ptr(void *p) 
# define _ASM_EXTABLE_TYPE_REG(from, to, type, reg)				\

	" .pushsection \"__ex_table\",\"a\"\n"					\

	" .balign 4\n"								\

	ANNOTATE_DATA_SPECIAL							\

	" .long (" #from ") - .\n"						\

	" .long (" #to ") - .\n"						\

	DEFINE_EXTABLE_TYPE_REG							\

arch/x86/include/asm/bug.h

+1 −0
Original line number Diff line number Diff line
@@ -57,6 +57,7 @@ 
#define _BUG_FLAGS_ASM(ins, file, line, flags, size, extra)		\

	"1:\t" ins "\n"							\

	".pushsection __bug_table,\"aw\"\n"				\

	ANNOTATE_DATA_SPECIAL						\

	__BUG_ENTRY(file, line, flags)					\

	"\t.org 2b + " size "\n"					\

	".popsection\n"							\

arch/x86/include/asm/cpufeature.h

+1 −0
Original line number Diff line number Diff line
@@ -101,6 +101,7 @@ static __always_inline bool _static_cpu_has(u16 bit) 
	asm goto(ALTERNATIVE_TERNARY("jmp 6f", %c[feature], "", "jmp %l[t_no]")

		".pushsection .altinstr_aux,\"ax\"\n"

		"6:\n"

		ANNOTATE_DATA_SPECIAL

		" testb %[bitnum], %a[cap_byte]\n"

		" jnz %l[t_yes]\n"

		" jmp %l[t_no]\n"

arch/x86/include/asm/jump_label.h

+1 −0
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#define JUMP_TABLE_ENTRY(key, label)			\

	".pushsection __jump_table,  \"aw\" \n\t"	\

	_ASM_ALIGN "\n\t"				\

	ANNOTATE_DATA_SPECIAL				\

	".long 1b - . \n\t"				\

	".long " label " - . \n\t"			\

	_ASM_PTR " " key " - . \n\t"			\