From: Peter Zijlstra <peterz@infradead.org>
Date: Fri, 8 Apr 2022 09:45:56 +0000 (+0200)
Subject: x86,objtool: Explicitly mark idtentry_body()s tail REACHABLE
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d66e9d50ea5cd76b2c4875c758efad665283d7ad;p=linux.git

x86,objtool: Explicitly mark idtentry_body()s tail REACHABLE

Objtool can figure out that some \cfunc()s are noreturn and then
complains about certain instances having unreachable tails:

  vmlinux.o: warning: objtool: asm_exc_xen_unknown_trap()+0x16: unreachable instruction

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220408094718.441854969@infradead.org
---

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 4faac48ebec5..73d958522b6a 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -337,6 +337,9 @@ SYM_CODE_END(ret_from_fork)
 
 	call	\cfunc
 
+	/* For some configurations \cfunc ends up being a noreturn. */
+	REACHABLE
+
 	jmp	error_return
 .endm