diff options
| author | Guilherme G. Piccoli <gpiccoli@igalia.com> | 2023-04-12 16:49:41 -0700 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2023-04-14 17:31:28 +0200 |
| commit | 611d4c716db0141cfc436994dc5aff1d69c924ad (patch) | |
| tree | e9ac00045ab1e399e41c4298bb66fa76a1b7279d /tools/objtool | |
| parent | 6e36a56a5f617262c0e8ae7e961487361c720b9e (diff) | |
x86/hyperv: Mark hv_ghcb_terminate() as noreturn
Annotate the function prototype and definition as noreturn to prevent
objtool warnings like:
vmlinux.o: warning: objtool: hyperv_init+0x55c: unreachable instruction
Also, as per Josh's suggestion, add it to the global_noreturns list.
As a comparison, an objdump output without the annotation:
[...]
1b63: mov $0x1,%esi
1b68: xor %edi,%edi
1b6a: callq ffffffff8102f680 <hv_ghcb_terminate>
1b6f: jmpq ffffffff82f217ec <hyperv_init+0x9c> # unreachable
1b74: cmpq $0xffffffffffffffff,-0x702a24(%rip)
[...]
Now, after adding the __noreturn to the function prototype:
[...]
17df: callq ffffffff8102f6d0 <hv_ghcb_negotiate_protocol>
17e4: test %al,%al
17e6: je ffffffff82f21bb9 <hyperv_init+0x469>
[...] <many insns>
1bb9: mov $0x1,%esi
1bbe: xor %edi,%edi
1bc0: callq ffffffff8102f680 <hv_ghcb_terminate>
1bc5: nopw %cs:0x0(%rax,%rax,1) # end of function
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/32453a703dfcf0d007b473c9acbf70718222b74b.1681342859.git.jpoimboe@kernel.org
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/check.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index e1b01ea6ad1b..5b600bbf2389 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -213,6 +213,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func, "ex_handler_msr_mce", "fortify_panic", "hlt_play_dead", + "hv_ghcb_terminate", "kthread_complete_and_exit", "kthread_exit", "kunit_try_catch_throw", |