linux/tools/objtool
Josh Poimboeuf 0afd0d9e0e objtool: Fix "noreturn" detection for recursive sibling calls
Objtool has some crude logic for detecting static "noreturn" functions
(aka "dead ends").  This is necessary for being able to correctly follow
GCC code flow when such functions are called.

It's remotely possible for two functions to call each other via sibling
calls.  If they don't have RET instructions, objtool's noreturn
detection logic goes into a recursive loop:

  drivers/char/ipmi/ipmi_ssif.o: warning: objtool: return_hosed_msg()+0x0: infinite recursion (objtool bug!)
  drivers/char/ipmi/ipmi_ssif.o: warning: objtool: deliver_recv_msg()+0x0: infinite recursion (objtool bug!)

Instead of reporting an error in this case, consider the functions to be
non-dead-ends.

Reported-and-tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: damian <damian.tometzki@icloud.com>
Link: http://lkml.kernel.org/r/7cc156408c5781a1f62085d352ced1fe39fe2f91.1525923412.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 10:20:53 +02:00
..
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
Documentation x86/asm: Fix inline asm call constraints for Clang 2017-09-23 15:06:20 +02:00
.gitignore objtool: Move synced files to their original relative locations 2017-11-07 10:48:23 +01:00
arch.h objtool: Assume unannotated UD2 instructions are dead ends 2017-07-28 08:33:32 +02:00
Build objtool: Add ORC unwind table generation 2017-07-18 10:57:43 +02:00
builtin-check.c objtool: Add module specific retpoline rules 2018-02-21 09:05:05 +01:00
builtin-orc.c objtool: Use existing global variables for options 2018-02-21 09:05:04 +01:00
builtin.h objtool: Add module specific retpoline rules 2018-02-21 09:05:05 +01:00
cfi.h objtool: Handle GCC stack pointer adjustment bug 2017-08-30 10:48:41 +02:00
check.c objtool: Fix "noreturn" detection for recursive sibling calls 2018-05-14 10:20:53 +02:00
check.h objtool: Add retpoline validation 2018-02-21 09:05:04 +01:00
elf.c objtool: Improve error message for bad file argument 2018-01-16 01:27:27 +01:00
elf.h objtool: Add ORC unwind table generation 2017-07-18 10:57:43 +02:00
Makefile objtool: Support HOSTCFLAGS and HOSTLDFLAGS 2018-04-17 07:59:42 +02:00
objtool.c objtool: Print top level commands on incorrect usage 2017-10-18 15:22:26 +02:00
orc_dump.c objtool: Fix 64-bit build on 32-bit host 2017-12-06 22:38:14 +01:00
orc_gen.c objtool: Warn on stripped section symbol 2018-01-30 15:09:23 +01:00
orc.h objtool: Move synced files to their original relative locations 2017-11-07 10:48:23 +01:00
special.c objtool: Implement stack validation 2.0 2017-06-30 10:19:19 +02:00
special.h
sync-check.sh objtool: Move kernel headers/code sync check to a script 2017-11-07 10:48:34 +01:00
warn.h objtool: Implement stack validation 2.0 2017-06-30 10:19:19 +02:00