Subject: Re: linux-next: build warning after merge of the powerpc tree

From: Josh Poimboeuf <[email-masked]>
Date: Thu, 16 Feb 2023 10:06:07 -0800

On Thu, Feb 16, 2023 at 02:40:31PM +1100, Stephen Rothwell wrote:
> Hi all,
> 
> After merging the powerpc tree, today's linux-next build (powerpc
> pseries_le_defconfig) produced this warning:
> 
> arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x6128: unannotated intra-function call
> 
> I have no idea what caused this.

Adding Sathvika and Christophe.

The short term fix would be something like the below, but...

If powerpc objtool is only doing mcount, does it even make sense to run
objtool on asm files?  If so, there are probably a lot more cleanups
needed for the asm code.

So I'm thinking either we should cleanup all the powerpc asm code with
annotations like below, or we should try to make objtool mcount-mode
ignore asm files.

diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 3a7266fa8a18..1febb56ebaeb 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -472,7 +472,7 @@ SYM_FUNC_START_LOCAL(__mmu_off)
 	b	.	/* prevent speculative execution */
 SYM_FUNC_END(__mmu_off)
 
-start_initialization_book3s:
+SYM_FUNC_START_LOCAL(start_initialization_book3s)
 	mflr	r25
 
 	/* Setup some critical 970 SPRs before switching MMU off */
@@ -494,6 +494,7 @@ start_initialization_book3s:
 
 	mtlr	r25
 	blr
+SYM_FUNC_END(start_initialization_book3s)
 #endif
 
 /*