Josh Poimboeuf 7dec80ccbe objtool: Detect RIP-relative switch table references, part 2 ... With the following commit: fd35c88b74 ("objtool: Support GCC 8 switch tables") I added a "can't find switch jump table" warning, to stop covering up silent failures if add_switch_table() can't find anything. That warning found yet another bug in the objtool switch table detection logic. For cases 1 and 2 (as described in the comments of find_switch_table()), the find_symbol_containing() check doesn't adjust the offset for RIP-relative switch jumps. Incidentally, this bug was already fixed for case 3 with: 6f5ec2993b ("objtool: Detect RIP-relative switch table references") However, that commit missed the fix for cases 1 and 2. The different cases are now starting to look more and more alike. So fix the bug by consolidating them into a single case, by checking the original dynamic jump instruction in the case 3 loop. This also simplifies the code and makes it more robust against future switch table detection issues -- of which I'm sure there will be many... Switch table detection has been the most fragile area of objtool, by far. I long for the day when we'll have a GCC plugin for annotating switch tables. Linus asked me to delay such a plugin due to the flakiness of the plugin infrastructure in older versions of GCC, so this rickety code is what we're stuck with for now. At least the code is now a little simpler than it was. Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/f400541613d45689086329432f3095119ffbc328.1526674218.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>		2018-05-19 08:10:04 +02:00
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arch/x86	objtool, kprobes/x86: Sync the latest <asm/insn.h> header with tools/objtool/arch/x86/include/asm/insn.h	2018-05-14 10:15:54 +02:00
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arch.h
Build
builtin-check.c
builtin-orc.c
builtin.h
cfi.h
check.c	objtool: Detect RIP-relative switch table references, part 2	2018-05-19 08:10:04 +02:00
check.h
elf.c	objtool: Support GCC 8's cold subfunctions	2018-05-14 10:20:53 +02:00
elf.h	objtool: Support GCC 8's cold subfunctions	2018-05-14 10:20:53 +02:00
Makefile	objtool: Support HOSTCFLAGS and HOSTLDFLAGS	2018-04-17 07:59:42 +02:00
objtool.c
orc_dump.c
orc_gen.c
orc.h
special.c
special.h
sync-check.sh
warn.h