Pull core x86 updates from Borislav Petkov: - Remove all the code around GS switching on 32-bit now that it is not needed anymore - Other misc improvements * tag 'x86_core_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: bug: Use normal relative pointers in 'struct bug_entry' x86/nmi: Make register_nmi_handler() more robust x86/asm: Merge load_gs_index() x86/32: Remove lazy GS macros ELF: Remove elf_core_copy_kernel_regs() x86/32: Simplify ELF_CORE_COPY_REGS
		
			
				
	
	
		
			90 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			90 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_X86_BUG_H
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#define _ASM_X86_BUG_H
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#include <linux/stringify.h>
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#include <linux/instrumentation.h>
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#include <linux/objtool.h>
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/*
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 * Despite that some emulators terminate on UD2, we use it for WARN().
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 */
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#define ASM_UD2		".byte 0x0f, 0x0b"
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#define INSN_UD2	0x0b0f
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#define LEN_UD2		2
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#ifdef CONFIG_GENERIC_BUG
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#ifdef CONFIG_X86_32
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# define __BUG_REL(val)	".long " __stringify(val)
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#else
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# define __BUG_REL(val)	".long " __stringify(val) " - ."
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#endif
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#ifdef CONFIG_DEBUG_BUGVERBOSE
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#define _BUG_FLAGS(ins, flags, extra)					\
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do {									\
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	asm_inline volatile("1:\t" ins "\n"				\
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		     ".pushsection __bug_table,\"aw\"\n"		\
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		     "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n"	\
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		     "\t"  __BUG_REL(%c0) "\t# bug_entry::file\n"	\
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		     "\t.word %c1"        "\t# bug_entry::line\n"	\
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		     "\t.word %c2"        "\t# bug_entry::flags\n"	\
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		     "\t.org 2b+%c3\n"					\
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		     ".popsection\n"					\
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		     extra						\
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		     : : "i" (__FILE__), "i" (__LINE__),		\
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			 "i" (flags),					\
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			 "i" (sizeof(struct bug_entry)));		\
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} while (0)
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#else /* !CONFIG_DEBUG_BUGVERBOSE */
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#define _BUG_FLAGS(ins, flags, extra)					\
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do {									\
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	asm_inline volatile("1:\t" ins "\n"				\
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		     ".pushsection __bug_table,\"aw\"\n"		\
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		     "2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n"	\
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		     "\t.word %c0"        "\t# bug_entry::flags\n"	\
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		     "\t.org 2b+%c1\n"					\
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		     ".popsection\n"					\
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		     extra						\
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		     : : "i" (flags),					\
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			 "i" (sizeof(struct bug_entry)));		\
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} while (0)
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#endif /* CONFIG_DEBUG_BUGVERBOSE */
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#else
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#define _BUG_FLAGS(ins, flags, extra)  asm volatile(ins)
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#endif /* CONFIG_GENERIC_BUG */
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#define HAVE_ARCH_BUG
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#define BUG()							\
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do {								\
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	instrumentation_begin();				\
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	_BUG_FLAGS(ASM_UD2, 0, "");				\
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	__builtin_unreachable();				\
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} while (0)
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/*
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 * This instrumentation_begin() is strictly speaking incorrect; but it
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 * suppresses the complaints from WARN()s in noinstr code. If such a WARN()
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 * were to trigger, we'd rather wreck the machine in an attempt to get the
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 * message out than not know about it.
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 */
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#define __WARN_FLAGS(flags)					\
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do {								\
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	__auto_type __flags = BUGFLAG_WARNING|(flags);		\
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	instrumentation_begin();				\
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	_BUG_FLAGS(ASM_UD2, __flags, ASM_REACHABLE);		\
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	instrumentation_end();					\
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} while (0)
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#include <asm-generic/bug.h>
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#endif /* _ASM_X86_BUG_H */
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