[PATCH v5 03/16] powerpc: Fix objtool unannotated intra-function call warnings

From: Sathvika Vasireddy
Date: Fri Oct 28 2022 - 10:35:05 EST

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@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Signed-off-by: Sathvika Vasireddy <sv@xxxxxxxxxxxxx>
---
arch/powerpc/kernel/exceptions-64s.S | 4 +++-
arch/powerpc/kernel/head_64.S | 7 +++++--
arch/powerpc/kernel/misc_64.S | 4 +++-
arch/powerpc/kernel/vector.S | 4 +++-
arch/powerpc/kvm/book3s_hv_interrupts.S | 4 +++-
arch/powerpc/kvm/book3s_hv_rmhandlers.S | 22 +++++++++++++++-------
6 files changed, 32 insertions(+), 13 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@xxxxxxxxxx)
*/

+#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
diff --git a/arch/powerpc/kvm/book3s_hv_interrupts.S b/arch/powerpc/kvm/book3s_hv_interrupts.S
index 59d89e4b154a..c0deeea7eef3 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupts.S
+++ b/arch/powerpc/kvm/book3s_hv_interrupts.S
@@ -9,6 +9,7 @@
* Authors: Alexander Graf <agraf@xxxxxxx>
*/

+#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)
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 37f50861dd98..a69d36cbf43b 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -10,6 +10,7 @@
* Authors: Alexander Graf <agraf@xxxxxxx>
*/

+#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
--
2.31.1