linux/tools/objtool
Josh Poimboeuf 4e32645cd8 x86/smp: Fix mwait_play_dead() and acpi_processor_ffh_play_dead() noreturn behavior
Fix some related issues (done in a single patch to avoid introducing
intermediate bisect warnings):

  1) The SMP version of mwait_play_dead() doesn't return, but its
     !SMP counterpart does.  Make its calling behavior consistent by
     resolving the !SMP version to a BUG().  It should never be called
     anyway, this just enforces that at runtime and enables its callers
     to be marked as __noreturn.

  2) While the SMP definition of mwait_play_dead() is annotated as
     __noreturn, the declaration isn't.  Nor is it listed in
     tools/objtool/noreturns.h.  Fix that.

  3) Similar to #1, the SMP version of acpi_processor_ffh_play_dead()
     doesn't return but its !SMP counterpart does.  Make the !SMP
     version a BUG().  It should never be called.

  4) acpi_processor_ffh_play_dead() doesn't return, but is lacking any
     __noreturn annotations.  Fix that.

This fixes the following objtool warnings:

  vmlinux.o: warning: objtool: acpi_processor_ffh_play_dead+0x67: mwait_play_dead() is missing a __noreturn annotation
  vmlinux.o: warning: objtool: acpi_idle_play_dead+0x3c: acpi_processor_ffh_play_dead() is missing a __noreturn annotation

Fixes: a7dd183f0b ("x86/smp: Allow calling mwait_play_dead with an arbitrary hint")
Fixes: 541ddf31e3 ("ACPI/processor_idle: Add FFH state handling")
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/e885c6fa9e96a61471b33e48c2162d28b15b14c5.1740962711.git.jpoimboe@kernel.org
2025-03-04 11:14:25 +01:00
..
arch objtool: Allow arch code to discover jump table size 2024-12-02 12:24:29 +01:00
Documentation x86/alternatives, kvm: Fix a couple of CALLs without a frame pointer 2024-07-01 12:41:11 +02:00
include/objtool objtool: Allow arch code to discover jump table size 2024-12-02 12:24:29 +01:00
.gitignore objtool: Install libsubcmd in build 2023-01-30 16:27:46 -08:00
Build objtool: Install libsubcmd in build 2023-01-30 16:27:46 -08:00
builtin-check.c objtool: Use "action" in error message to be consistent with help 2024-07-02 23:40:24 -07:00
check.c - Move a warning about a lld.ld breakage into the verbose setting as said 2025-02-16 10:30:58 -08:00
elf.c objtool: Fix unreachable instruction warnings for weak functions 2024-11-06 22:41:10 +09:00
Makefile objtool: Also include tools/include/uapi 2024-10-17 15:13:06 -07:00
noreturns.h x86/smp: Fix mwait_play_dead() and acpi_processor_ffh_play_dead() noreturn behavior 2025-03-04 11:14:25 +01:00
objtool.c objtool: Propagate early errors 2023-10-05 17:01:11 -07:00
orc_dump.c objtool/x86: Separate arch-specific and generic parts 2024-03-11 22:23:47 +08:00
orc_gen.c objtool/x86: Separate arch-specific and generic parts 2024-03-11 22:23:47 +08:00
special.c x86/alternatives: Add nested alternatives macros 2024-06-11 17:13:08 +02:00
sync-check.sh objtool: Add objtool_types.h 2023-03-23 23:18:56 +01:00
weak.c objtool: Ditch subcommands 2022-04-22 12:32:01 +02:00