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: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: NChristophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: NJosh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: NSathvika Vasireddy <sv@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221114175754.1131267-4-sv@linux.ibm.com

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)

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

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(),

arch/powerpc/kernel/vector.S

 /* 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

arch/powerpc/kvm/book3s_hv_interrupts.S

@@ -9,6 +9,7 @@
  * Authors: Alexander Graf <agraf@suse.de>
  */
 
+#include <linux/linkage.h>
 #include <asm/ppc_asm.h>
 #include <asm/kvm_asm.h>
 #include <asm/reg.h>
@@ -107,7 +108,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 /*
  * void kvmhv_save_host_pmu(void)
  */
-kvmhv_save_host_pmu:
+SYM_FUNC_START_LOCAL(kvmhv_save_host_pmu)
 BEGIN_FTR_SECTION
 	/* Work around P8 PMAE bug */
 	li	r3, -1
@@ -154,3 +155,4 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	stw	r8, HSTATE_PMC5(r13)
 	stw	r9, HSTATE_PMC6(r13)
 31:	blr
+SYM_FUNC_END(kvmhv_save_host_pmu)

arch/powerpc/kvm/book3s_hv_rmhandlers.S

@@ -10,6 +10,7 @@
  * Authors: Alexander Graf <agraf@suse.de>
  */
 
+#include <linux/linkage.h>
 #include <asm/ppc_asm.h>
 #include <asm/code-patching-asm.h>
 #include <asm/kvm_asm.h>
@@ -2358,7 +2359,7 @@ hmi_realmode:
  * This routine calls kvmppc_read_intr, a C function, if an external
  * interrupt is pending.
  */
-kvmppc_check_wake_reason:
+SYM_FUNC_START_LOCAL(kvmppc_check_wake_reason)
 	mfspr	r6, SPRN_SRR1
 BEGIN_FTR_SECTION
 	rlwinm	r6, r6, 45-31, 0xf	/* extract wake reason field (P8) */
@@ -2427,6 +2428,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	addi	r1, r1, PPC_MIN_STKFRM
 	mtlr	r0
 	blr
+SYM_FUNC_END(kvmppc_check_wake_reason)
 
 /*
  * Save away FP, VMX and VSX registers.
@@ -2434,7 +2436,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
  * N.B. r30 and r31 are volatile across this function,
  * thus it is not callable from C.
  */
-kvmppc_save_fp:
+SYM_FUNC_START_LOCAL(kvmppc_save_fp)
 	mflr	r30
 	mr	r31,r3
 	mfmsr	r5
@@ -2462,6 +2464,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	stw	r6,VCPU_VRSAVE(r31)
 	mtlr	r30
 	blr
+SYM_FUNC_END(kvmppc_save_fp)
 
 /*
  * Load up FP, VMX and VSX registers
@@ -2469,7 +2472,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
  * N.B. r30 and r31 are volatile across this function,
  * thus it is not callable from C.
  */
-kvmppc_load_fp:
+SYM_FUNC_START_LOCAL(kvmppc_load_fp)
 	mflr	r30
 	mr	r31,r4
 	mfmsr	r9
@@ -2498,6 +2501,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	mtlr	r30
 	mr	r4,r31
 	blr
+SYM_FUNC_END(kvmppc_load_fp)
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 /*
@@ -2746,7 +2750,7 @@ kvmppc_bad_host_intr:
  *   r9 has a vcpu pointer (in)
  *   r0 is used as a scratch register
  */
-kvmppc_msr_interrupt:
+SYM_FUNC_START_LOCAL(kvmppc_msr_interrupt)
 	rldicl	r0, r11, 64 - MSR_TS_S_LG, 62
 	cmpwi	r0, 2 /* Check if we are in transactional state..  */
 	ld	r11, VCPU_INTR_MSR(r9)
@@ -2755,13 +2759,14 @@ kvmppc_msr_interrupt:
 	li	r0, 1
 1:	rldimi	r11, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
 	blr
+SYM_FUNC_END(kvmppc_msr_interrupt)
 
 /*
  * void kvmhv_load_guest_pmu(struct kvm_vcpu *vcpu)
  *
  * Load up guest PMU state.  R3 points to the vcpu struct.
  */
-kvmhv_load_guest_pmu:
+SYM_FUNC_START_LOCAL(kvmhv_load_guest_pmu)
 	mr	r4, r3
 	mflr	r0
 	li	r3, 1
@@ -2811,13 +2816,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	isync
 	mtlr	r0
 	blr
+SYM_FUNC_END(kvmhv_load_guest_pmu)
 
 /*
  * void kvmhv_load_host_pmu(void)
  *
  * Reload host PMU state saved in the PACA by kvmhv_save_host_pmu.
  */
-kvmhv_load_host_pmu:
+SYM_FUNC_START_LOCAL(kvmhv_load_host_pmu)
 	mflr	r0
 	lbz	r4, PACA_PMCINUSE(r13) /* is the host using the PMU? */
 	cmpwi	r4, 0
@@ -2859,6 +2865,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	isync
 	mtlr	r0
 23:	blr
+SYM_FUNC_END(kvmhv_load_host_pmu)
 
 /*
  * void kvmhv_save_guest_pmu(struct kvm_vcpu *vcpu, bool pmu_in_use)
@@ -2866,7 +2873,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
  * Save guest PMU state into the vcpu struct.
  * r3 = vcpu, r4 = full save flag (PMU in use flag set in VPA)
  */
-kvmhv_save_guest_pmu:
+SYM_FUNC_START_LOCAL(kvmhv_save_guest_pmu)
 	mr	r9, r3
 	mr	r8, r4
 BEGIN_FTR_SECTION
@@ -2942,6 +2949,7 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_MMCRS, r4
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 22:	blr
+SYM_FUNC_END(kvmhv_save_guest_pmu)
 
 /*
  * This works around a hardware bug on POWER8E processors, where