powerpc: Fix objtool unannotated intra-function call warnings

Objtool throws unannotated intra-function call warnings in the following
assembly files:

arch/powerpc/kernel/vector.o: warning: objtool: .text+0x53c: unannotated intra-function call

arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x60: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x124: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x5d4: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x5dc: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0xcb8: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0xd0c: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x1030: unannotated intra-function call

arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x358: unannotated intra-function call
arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x728: unannotated intra-function call
arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x4d94: unannotated intra-function call
arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x4ec4: unannotated intra-function call

arch/powerpc/kvm/book3s_hv_interrupts.o: warning: objtool: .text+0x6c: unannotated intra-function call
arch/powerpc/kernel/misc_64.o: warning: objtool: .text+0x64: unannotated intra-function call

Objtool does not add STT_NOTYPE symbols with size 0 to the rbtree, which
is why find_call_destination() function is not able to find the
destination symbol for 'bl' instruction. For such symbols, objtool is
throwing unannotated intra-function call warnings in assembly files. Fix
these warnings by annotating those symbols with SYM_FUNC_START_LOCAL and
SYM_FUNC_END macros, inorder to set symbol type to STT_FUNC and symbol
size accordingly.

Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221114175754.1131267-4-sv@linux.ibm.com

4 files changed, 14 insertions, 5 deletions

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 5381a43e50fe..77201ad9f329 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -13,6 +13,7 @@
  *
  */
 
+#include <linux/linkage.h>
 #include <asm/hw_irq.h>
 #include <asm/exception-64s.h>
 #include <asm/ptrace.h>
@@ -3112,7 +3113,7 @@ _GLOBAL(enable_machine_check)
 	blr
 
 /* MSR[RI] should be clear because this uses SRR[01] */
-disable_machine_check:
+SYM_FUNC_START_LOCAL(disable_machine_check)
 	mflr	r0
 	bcl	20,31,$+4
 0:	mflr	r3
@@ -3125,3 +3126,4 @@ disable_machine_check:
 	RFI_TO_KERNEL
 1:	mtlr	r0
 	blr
+SYM_FUNC_END(disable_machine_check)
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index dedcc6fe2263..874efd25cc45 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -18,6 +18,7 @@
  *  variants.
  */
 
+#include <linux/linkage.h>
 #include <linux/threads.h>
 #include <linux/init.h>
 #include <asm/reg.h>
@@ -462,7 +463,7 @@ generic_secondary_common_init:
  * Assumes we're mapped EA == RA if the MMU is on.
  */
 #ifdef CONFIG_PPC_BOOK3S
-__mmu_off:
+SYM_FUNC_START_LOCAL(__mmu_off)
 	mfmsr	r3
 	andi.	r0,r3,MSR_IR|MSR_DR
 	beqlr
@@ -473,6 +474,7 @@ __mmu_off:
 	sync
 	rfid
 	b	.	/* prevent speculative execution */
+SYM_FUNC_END(__mmu_off)
 #endif
 
 
@@ -869,7 +871,7 @@ _GLOBAL(start_secondary_resume)
 /*
  * This subroutine clobbers r11 and r12
  */
-enable_64b_mode:
+SYM_FUNC_START_LOCAL(enable_64b_mode)
 	mfmsr	r11			/* grab the current MSR */
 #ifdef CONFIG_PPC_BOOK3E_64
 	oris	r11,r11,0x8000		/* CM bit set, we'll set ICM later */
@@ -881,6 +883,7 @@ enable_64b_mode:
 	isync
 #endif
 	blr
+SYM_FUNC_END(enable_64b_mode)
 
 /*
  * This puts the TOC pointer into r2, offset by 0x8000 (as expected
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 36184cada00b..c61a7ba446a8 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -9,6 +9,7 @@
  * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
  */
 
+#include <linux/linkage.h>
 #include <linux/sys.h>
 #include <asm/unistd.h>
 #include <asm/errno.h>
@@ -353,7 +354,7 @@ _GLOBAL(kexec_smp_wait)
  *
  * don't overwrite r3 here, it is live for kexec_wait above.
  */
-real_mode:	/* assume normal blr return */
+SYM_FUNC_START_LOCAL(real_mode)	/* assume normal blr return */
 #ifdef CONFIG_PPC_BOOK3E_64
 	/* Create an identity mapping. */
 	b	kexec_create_tlb
@@ -370,6 +371,7 @@ real_mode:	/* assume normal blr return */
 	mtspr	SPRN_SRR0,r11
 	rfid
 #endif
+SYM_FUNC_END(real_mode)
 
 /*
  * kexec_sequence(newstack, start, image, control, clear_all(),
diff --git a/arch/powerpc/kernel/vector.S b/arch/powerpc/kernel/vector.S
index 5cf64740edb8..ffe5d90abe17 100644
--- a/arch/powerpc/kernel/vector.S
+++ b/arch/powerpc/kernel/vector.S
@@ -1,4 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/linkage.h>
 #include <asm/processor.h>
 #include <asm/ppc_asm.h>
 #include <asm/reg.h>
@@ -185,7 +186,7 @@ fphalf:
  * Internal routine to enable floating point and set FPSCR to 0.
  * Don't call it from C; it doesn't use the normal calling convention.
  */
-fpenable:
+SYM_FUNC_START_LOCAL(fpenable)
 #ifdef CONFIG_PPC32
 	stwu	r1,-64(r1)
 #else
@@ -202,6 +203,7 @@ fpenable:
 	mffs	fr31
 	MTFSF_L(fr1)
 	blr
+SYM_FUNC_END(fpenable)
 
 fpdisable:
 	mtlr	r12