1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef _ASM_X86_BUG_H
 3#define _ASM_X86_BUG_H
 4
 5#include <linux/stringify.h>
 
 
 6
 7/*
 8 * Despite that some emulators terminate on UD2, we use it for WARN().
 9 *
10 * Since various instruction decoders/specs disagree on the encoding of
11 * UD0/UD1.
12 */
13
14#define ASM_UD0		".byte 0x0f, 0xff" /* + ModRM (for Intel) */
15#define ASM_UD1		".byte 0x0f, 0xb9" /* + ModRM */
16#define ASM_UD2		".byte 0x0f, 0x0b"
17
18#define INSN_UD0	0xff0f
19#define INSN_UD2	0x0b0f
20
21#define LEN_UD2		2
22
23#ifdef CONFIG_GENERIC_BUG
24
25#ifdef CONFIG_X86_32
26# define __BUG_REL(val)	".long " __stringify(val)
27#else
28# define __BUG_REL(val)	".long " __stringify(val) " - 2b"
29#endif
30
31#ifdef CONFIG_DEBUG_BUGVERBOSE
32
33#define _BUG_FLAGS(ins, flags)						\
34do {									\
35	asm volatile("1:\t" ins "\n"					\
36		     ".pushsection __bug_table,\"aw\"\n"		\
37		     "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n"	\
38		     "\t"  __BUG_REL(%c0) "\t# bug_entry::file\n"	\
39		     "\t.word %c1"        "\t# bug_entry::line\n"	\
40		     "\t.word %c2"        "\t# bug_entry::flags\n"	\
41		     "\t.org 2b+%c3\n"					\
42		     ".popsection"					\
 
43		     : : "i" (__FILE__), "i" (__LINE__),		\
44			 "i" (flags),					\
45			 "i" (sizeof(struct bug_entry)));		\
46} while (0)
47
48#else /* !CONFIG_DEBUG_BUGVERBOSE */
49
50#define _BUG_FLAGS(ins, flags)						\
51do {									\
52	asm volatile("1:\t" ins "\n"					\
53		     ".pushsection __bug_table,\"aw\"\n"		\
54		     "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n"	\
55		     "\t.word %c0"        "\t# bug_entry::flags\n"	\
56		     "\t.org 2b+%c1\n"					\
57		     ".popsection"					\
 
58		     : : "i" (flags),					\
59			 "i" (sizeof(struct bug_entry)));		\
60} while (0)
61
62#endif /* CONFIG_DEBUG_BUGVERBOSE */
63
64#else
65
66#define _BUG_FLAGS(ins, flags)  asm volatile(ins)
67
68#endif /* CONFIG_GENERIC_BUG */
69
70#define HAVE_ARCH_BUG
71#define BUG()							\
72do {								\
73	_BUG_FLAGS(ASM_UD2, 0);					\
74	unreachable();						\
 
75} while (0)
76
 
 
 
 
 
 
77#define __WARN_FLAGS(flags)					\
78do {								\
79	_BUG_FLAGS(ASM_UD2, BUGFLAG_WARNING|(flags));		\
80	annotate_reachable();					\
 
 
81} while (0)
82
83#include <asm-generic/bug.h>
84
85#endif /* _ASM_X86_BUG_H */

 1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef _ASM_X86_BUG_H
 3#define _ASM_X86_BUG_H
 4
 5#include <linux/stringify.h>
 6#include <linux/instrumentation.h>
 7#include <linux/objtool.h>
 8
 9/*
10 * Despite that some emulators terminate on UD2, we use it for WARN().
 
 
 
11 */
 
 
 
12#define ASM_UD2		".byte 0x0f, 0x0b"
 
 
13#define INSN_UD2	0x0b0f
 
14#define LEN_UD2		2
15
16#ifdef CONFIG_GENERIC_BUG
17
18#ifdef CONFIG_X86_32
19# define __BUG_REL(val)	".long " __stringify(val)
20#else
21# define __BUG_REL(val)	".long " __stringify(val) " - ."
22#endif
23
24#ifdef CONFIG_DEBUG_BUGVERBOSE
25
26#define _BUG_FLAGS(ins, flags, extra)					\
27do {									\
28	asm_inline volatile("1:\t" ins "\n"				\
29		     ".pushsection __bug_table,\"aw\"\n"		\
30		     "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n"	\
31		     "\t"  __BUG_REL(%c0) "\t# bug_entry::file\n"	\
32		     "\t.word %c1"        "\t# bug_entry::line\n"	\
33		     "\t.word %c2"        "\t# bug_entry::flags\n"	\
34		     "\t.org 2b+%c3\n"					\
35		     ".popsection\n"					\
36		     extra						\
37		     : : "i" (__FILE__), "i" (__LINE__),		\
38			 "i" (flags),					\
39			 "i" (sizeof(struct bug_entry)));		\
40} while (0)
41
42#else /* !CONFIG_DEBUG_BUGVERBOSE */
43
44#define _BUG_FLAGS(ins, flags, extra)					\
45do {									\
46	asm_inline volatile("1:\t" ins "\n"				\
47		     ".pushsection __bug_table,\"aw\"\n"		\
48		     "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n"	\
49		     "\t.word %c0"        "\t# bug_entry::flags\n"	\
50		     "\t.org 2b+%c1\n"					\
51		     ".popsection\n"					\
52		     extra						\
53		     : : "i" (flags),					\
54			 "i" (sizeof(struct bug_entry)));		\
55} while (0)
56
57#endif /* CONFIG_DEBUG_BUGVERBOSE */
58
59#else
60
61#define _BUG_FLAGS(ins, flags, extra)  asm volatile(ins)
62
63#endif /* CONFIG_GENERIC_BUG */
64
65#define HAVE_ARCH_BUG
66#define BUG()							\
67do {								\
68	instrumentation_begin();				\
69	_BUG_FLAGS(ASM_UD2, 0, "");				\
70	__builtin_unreachable();				\
71} while (0)
72
73/*
74 * This instrumentation_begin() is strictly speaking incorrect; but it
75 * suppresses the complaints from WARN()s in noinstr code. If such a WARN()
76 * were to trigger, we'd rather wreck the machine in an attempt to get the
77 * message out than not know about it.
78 */
79#define __WARN_FLAGS(flags)					\
80do {								\
81	__auto_type __flags = BUGFLAG_WARNING|(flags);		\
82	instrumentation_begin();				\
83	_BUG_FLAGS(ASM_UD2, __flags, ASM_REACHABLE);		\
84	instrumentation_end();					\
85} while (0)
86
87#include <asm-generic/bug.h>
88
89#endif /* _ASM_X86_BUG_H */