Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'objtool_urgent_for_v5.17_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool fix from Borislav Petkov:
"Fix a case where objtool would mistakenly warn about instructions
being unreachable"
* tag 'objtool_urgent_for_v5.17_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/bug: Merge annotate_reachable() into _BUG_FLAGS() asm
+16
-25
+11
-9
arch/x86/include/asm/bug.h
+11
-9
arch/x86/include/asm/bug.h
···
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#ifdef CONFIG_DEBUG_BUGVERBOSE
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#define _BUG_FLAGS(ins, flags) \
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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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"\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" \
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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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#else /* !CONFIG_DEBUG_BUGVERBOSE */
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#define _BUG_FLAGS(ins, flags) \
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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" \
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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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#else
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#define _BUG_FLAGS(ins, flags) asm volatile(ins)
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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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···
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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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unreachable(); \
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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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*/
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#define __WARN_FLAGS(flags) \
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do { \
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__auto_type f = BUGFLAG_WARNING|(flags); \
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instrumentation_begin(); \
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_BUG_FLAGS(ASM_UD2, BUGFLAG_WARNING|(flags)); \
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annotate_reachable(); \
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_BUG_FLAGS(ASM_UD2, f, ASM_REACHABLE); \
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instrumentation_end(); \
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} while (0)
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+5
-16
include/linux/compiler.h
+5
-16
include/linux/compiler.h
···
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*/
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#define __stringify_label(n) #n
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#define __annotate_reachable(c) ({ \
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asm volatile(__stringify_label(c) ":\n\t" \
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".pushsection .discard.reachable\n\t" \
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".long " __stringify_label(c) "b - .\n\t" \
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".popsection\n\t" : : "i" (c)); \
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})
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#define annotate_reachable() __annotate_reachable(__COUNTER__)
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#define __annotate_unreachable(c) ({ \
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asm volatile(__stringify_label(c) ":\n\t" \
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".pushsection .discard.unreachable\n\t" \
···
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})
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#define annotate_unreachable() __annotate_unreachable(__COUNTER__)
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#define ASM_UNREACHABLE \
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"999:\n\t" \
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".pushsection .discard.unreachable\n\t" \
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".long 999b - .\n\t" \
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#define ASM_REACHABLE \
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"998:\n\t" \
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".pushsection .discard.reachable\n\t" \
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".long 998b - .\n\t" \
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".popsection\n\t"
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/* Annotate a C jump table to allow objtool to follow the code flow */
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#define __annotate_jump_table __section(".rodata..c_jump_table")
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#else
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#define annotate_reachable()
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#define annotate_unreachable()
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# define ASM_REACHABLE
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#define __annotate_jump_table
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#endif
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#ifndef ASM_UNREACHABLE
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# define ASM_UNREACHABLE
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#endif
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#ifndef unreachable
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# define unreachable() do { \
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annotate_unreachable(); \