Commit bb817006 authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

objtool: Collect more annotations in objtool.h 



Suggested-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarJosh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/20241128094311.786598147@infradead.org
parent a8a330dd

arch/x86/include/asm/alternative.h

+0 −12
Original line number Diff line number Diff line
@@ -55,12 +55,6 @@ 
#define LOCK_PREFIX ""

#endif



/*

 * objtool annotation to ignore the alternatives and only consider the original

 * instruction(s).

 */

#define ANNOTATE_IGNORE_ALTERNATIVE	ASM_ANNOTATE(ANNOTYPE_IGNORE_ALTS)



/*

 * The patching flags are part of the upper bits of the @ft_flags parameter when

 * specifying them. The split is currently like this:
@@ -307,12 +301,6 @@ void nop_func(void); 
	.endm

#endif



/*

 * objtool annotation to ignore the alternatives and only consider the original

 * instruction(s).

 */

#define ANNOTATE_IGNORE_ALTERNATIVE ANNOTATE type=ANNOTYPE_IGNORE_ALTS



/*

 * Issue one struct alt_instr descriptor entry (need to put it into

 * the section .altinstructions, see below). This entry contains

arch/x86/include/asm/nospec-branch.h

+0 −9
Original line number Diff line number Diff line
@@ -179,13 +179,6 @@ 


#ifdef __ASSEMBLY__



/*

 * This should be used immediately before an indirect jump/call. It tells

 * objtool the subsequent indirect jump/call is vouched safe for retpoline

 * builds.

 */

#define ANNOTATE_RETPOLINE_SAFE	ANNOTATE type=ANNOTYPE_RETPOLINE_SAFE



/*

 * (ab)use RETPOLINE_SAFE on RET to annotate away 'bare' RET instructions

 * vs RETBleed validation.
@@ -345,8 +338,6 @@ 


#else /* __ASSEMBLY__ */



#define ANNOTATE_RETPOLINE_SAFE ASM_ANNOTATE(ANNOTYPE_RETPOLINE_SAFE)



typedef u8 retpoline_thunk_t[RETPOLINE_THUNK_SIZE];

extern retpoline_thunk_t __x86_indirect_thunk_array[];

extern retpoline_thunk_t __x86_indirect_call_thunk_array[];

include/linux/instrumentation.h

+2 −2
Original line number Diff line number Diff line
@@ -10,7 +10,7 @@ 
/* Begin/end of an instrumentation safe region */

#define __instrumentation_begin(c) ({					\

	asm volatile(__stringify(c) ": nop\n\t"				\

		     __ASM_ANNOTATE(__ASM_BREF(c), ANNOTYPE_INSTR_BEGIN)\

		     ANNOTATE_INSTR_BEGIN(__ASM_BREF(c))		\

		     : : "i" (c));					\

})

#define instrumentation_begin() __instrumentation_begin(__COUNTER__)
@@ -48,7 +48,7 @@ 
 */

#define __instrumentation_end(c) ({					\

	asm volatile(__stringify(c) ": nop\n\t"				\

		     __ASM_ANNOTATE(__ASM_BREF(c), ANNOTYPE_INSTR_END)	\

		     ANNOTATE_INSTR_END(__ASM_BREF(c))			\

		     : : "i" (c));					\

})

#define instrumentation_end() __instrumentation_end(__COUNTER__)

include/linux/objtool.h

+53 −27
Original line number Diff line number Diff line
@@ -63,8 +63,6 @@ 
	"911:\n\t"						\

	__ASM_ANNOTATE(911b, type)



#define ANNOTATE_NOENDBR	ASM_ANNOTATE(ANNOTYPE_NOENDBR)



#else /* __ASSEMBLY__ */



/*
@@ -113,19 +111,6 @@ 
#endif

.endm



/*

 * Use objtool to validate the entry requirement that all code paths do

 * VALIDATE_UNRET_END before RET.

 *

 * NOTE: The macro must be used at the beginning of a global symbol, otherwise

 * it will be ignored.

 */

#if defined(CONFIG_NOINSTR_VALIDATION) && \

	(defined(CONFIG_MITIGATION_UNRET_ENTRY) || defined(CONFIG_MITIGATION_SRSO))

#define VALIDATE_UNRET_BEGIN	ANNOTATE type=ANNOTYPE_UNRET_BEGIN

#else

#define VALIDATE_UNRET_BEGIN

#endif



.macro REACHABLE

.Lhere_\@:
@@ -142,14 +127,6 @@ 
	.popsection

.endm



#define ANNOTATE_NOENDBR	ANNOTATE type=ANNOTYPE_NOENDBR



/*

 * This macro indicates that the following intra-function call is valid.

 * Any non-annotated intra-function call will cause objtool to issue a warning.

 */

#define ANNOTATE_INTRA_FUNCTION_CALL ANNOTATE type=ANNOTYPE_INTRA_FUNCTION_CALL



#endif /* __ASSEMBLY__ */



#else /* !CONFIG_OBJTOOL */
@@ -161,16 +138,12 @@ 
#define STACK_FRAME_NON_STANDARD_FP(func)

#define __ASM_ANNOTATE(label, type)

#define ASM_ANNOTATE(type)

#define ANNOTATE_NOENDBR

#define ASM_REACHABLE

#else

#define ANNOTATE_INTRA_FUNCTION_CALL

.macro UNWIND_HINT type:req sp_reg=0 sp_offset=0 signal=0

.endm

.macro STACK_FRAME_NON_STANDARD func:req

.endm

.macro ANNOTATE_NOENDBR

.endm

.macro REACHABLE

.endm

.macro ANNOTATE type:req
@@ -179,4 +152,57 @@ 


#endif /* CONFIG_OBJTOOL */



#ifndef __ASSEMBLY__

/*

 * Annotate away the various 'relocation to !ENDBR` complaints; knowing that

 * these relocations will never be used for indirect calls.

 */

#define ANNOTATE_NOENDBR		ASM_ANNOTATE(ANNOTYPE_NOENDBR)

/*

 * This should be used immediately before an indirect jump/call. It tells

 * objtool the subsequent indirect jump/call is vouched safe for retpoline

 * builds.

 */

#define ANNOTATE_RETPOLINE_SAFE		ASM_ANNOTATE(ANNOTYPE_RETPOLINE_SAFE)

/*

 * See linux/instrumentation.h

 */

#define ANNOTATE_INSTR_BEGIN(label)	__ASM_ANNOTATE(label, ANNOTYPE_INSTR_BEGIN)

#define ANNOTATE_INSTR_END(label)	__ASM_ANNOTATE(label, ANNOTYPE_INSTR_END)

/*

 * objtool annotation to ignore the alternatives and only consider the original

 * instruction(s).

 */

#define ANNOTATE_IGNORE_ALTERNATIVE	ASM_ANNOTATE(ANNOTYPE_IGNORE_ALTS)

/*

 * This macro indicates that the following intra-function call is valid.

 * Any non-annotated intra-function call will cause objtool to issue a warning.

 */

#define ANNOTATE_INTRA_FUNCTION_CALL	ASM_ANNOTATE(ANNOTYPE_INTRA_FUNCTION_CALL)

/*

 * Use objtool to validate the entry requirement that all code paths do

 * VALIDATE_UNRET_END before RET.

 *

 * NOTE: The macro must be used at the beginning of a global symbol, otherwise

 * it will be ignored.

 */

#define ANNOTATE_UNRET_BEGIN		ASM_ANNOTATE(ANNOTYPE_UNRET_BEGIN)



#else

#define ANNOTATE_NOENDBR		ANNOTATE type=ANNOTYPE_NOENDBR

#define ANNOTATE_RETPOLINE_SAFE		ANNOTATE type=ANNOTYPE_RETPOLINE_SAFE

/*	ANNOTATE_INSTR_BEGIN		ANNOTATE type=ANNOTYPE_INSTR_BEGIN */

/*	ANNOTATE_INSTR_END		ANNOTATE type=ANNOTYPE_INSTR_END */

#define ANNOTATE_IGNORE_ALTERNATIVE	ANNOTATE type=ANNOTYPE_IGNORE_ALTS

#define ANNOTATE_INTRA_FUNCTION_CALL	ANNOTATE type=ANNOTYPE_INTRA_FUNCTION_CALL

#define ANNOTATE_UNRET_BEGIN		ANNOTATE type=ANNOTYPE_UNRET_BEGIN

#endif



#if defined(CONFIG_NOINSTR_VALIDATION) && \

	(defined(CONFIG_MITIGATION_UNRET_ENTRY) || defined(CONFIG_MITIGATION_SRSO))

#define VALIDATE_UNRET_BEGIN	ANNOTATE_UNRET_BEGIN

#else

#define VALIDATE_UNRET_BEGIN

#endif



#endif /* _LINUX_OBJTOOL_H */