[PATCH v4 00/16] objtool: Enable and implement --mcount option on powerpc

[PATCH v4 00/16] objtool: Enable and implement --mcount option on powerpc

[Sathvika Vasireddy]

This patchset enables and implements objtool --mcount
option on powerpc. This applies atop powerpc/merge branch.

Changelog:

----
v4:

* Patch 11/16 - Introduce a new config option
		CONFIG_HAVE_OBJTOOL_NOP_MCOUNT as a means for
		architectures to enable nop'ing ftrace locations.

	      - Remove Acked-by tag from Peter Zijlstra (Intel),
		and Reviewed-by tag from Christophe Leroy. 
		[This is done because I reworked the patch to add
		a new config option to objtool. Please let me know
		if you want me to retain the tags. Thanks!]

* Patch 16/16 - Rework the patch to handle only 'bl' instruction
		decoding. 

----
v3:

* Patch 01/16 - Rework patch subject.
              - Rework changelog.
              - Add Reviewed-by tag from Christophe Leroy.

* Patch 02/16 - Rework changelog to update details based on feedback
                from Nicholas Piggin and Michael Ellerman.
              - Use quotes instead of __stringify macro, based on
                suggestion from Christophe Leroy.

* Patch 03/16 - Add Reviewed-by tag from Christophe Leroy.
              - Based on Christophe's suggestion, keep all <linux/...>
                before <asm/...>.
              - Rework changelog.

* Patch 04/16 - Add Reviewed-by tag from Christophe Leroy.

* Patch 05/16 - Add Reviewed-by tag from Christophe Leroy.

* Patch 06/16 - No change.

* Patch 07/16 - Add Reviewed-by tag from Christophe Leroy.

* Patch 08/16 - Add Acked-by tag from Peter Zijlstra.

* Patch 09/16 - Add Acked-by tag from Peter Zijlstra.

* Patch 10/16 - Reorder local variable declarations to use reverse
                xmas tree format.
              - Add Signed-off-by tag from Sathvika Vasireddy indicating
                changes done.
              - Add Acked-by tag from Peter Zijlstra.

* Patch 11/16 - Update changelog to indicate that powerpc kernel does
                not support nop'ed out ftrace locations.
              - Add Acked-by tag from Peter Zijlstra.
              - Add Reviewed-by tag from Christophe Leroy.

* Patch 12/16 - Per Christophe's comment, rework changelog.

* Patch 13/16 - Add Acked-by tag from Peter Zijlstra.
              - Add Reviewed-by tag from Christophe Leroy.

* Patch 14/16 - Simplify arch_ftrace_match() function, based on
                Christophe's suggestion.
              - Add Reviewed-by tag from Christophe Leroy.

* Patch 15/16 - Include code from Christophe Leroy to use local vars for
                type and imm, and to adapt len for prefixed
                instructions.

* Patch 16/16 - Based on suggestion from Christophe Leroy, setup
                immediate value calculation outside the check for
                specific instruction under case 18.
              - Set instruction type to INSN_CALL for 'bla'
                instruction as well.

----
v2:

* Change subject of patch 01/16
* As suggested by Christophe Leroy, add barrier_before_unreachable()
before __builtin_unreachable() to work around a gcc problem.
* Fix issues reported by Kernel Test Robot.
* Include suggestions from Christophe Leroy, and change commit
messages for patches 01/16, 02/16, 03/16, 05/16.

----

Christophe Leroy (4):
  objtool: Fix SEGFAULT
  objtool: Use target file endianness instead of a compiled constant
  objtool: Use target file class size instead of a compiled constant
  powerpc: Fix objtool unannotated intra-function call warnings on PPC32

Sathvika Vasireddy (12):
  powerpc: Fix __WARN_FLAGS() for use with Objtool
  powerpc: Override __ALIGN and __ALIGN_STR macros
  powerpc: Fix objtool unannotated intra-function call warnings
  powerpc: Curb objtool unannotated intra-function warnings
  powerpc: Skip objtool from running on drivers/crypto/vmx/aesp8-ppc.o
  powerpc: Skip objtool from running on VDSO files
  objtool: Add --mnop as an option to --mcount
  objtool: Read special sections with alts only when specific options are selected
  objtool: Use macros to define arch specific reloc types
  objtool: Add arch specific function arch_ftrace_match()
  objtool/powerpc: Enable objtool to be built on ppc
  objtool/powerpc: Add --mcount specific implementation


 Makefile                                      |   4 +-
 arch/powerpc/Kconfig                          |   2 +
 arch/powerpc/include/asm/asm.h                |   7 ++
 arch/powerpc/include/asm/bug.h                |   3 +-
 arch/powerpc/include/asm/linkage.h            |   3 +
 arch/powerpc/kernel/cpu_setup_6xx.S           |  26 +++--
 arch/powerpc/kernel/cpu_setup_fsl_booke.S     |   8 +-
 arch/powerpc/kernel/entry_32.S                |   9 +-
 arch/powerpc/kernel/entry_64.S                |   2 +
 arch/powerpc/kernel/exceptions-64s.S          |   7 +-
 arch/powerpc/kernel/head_40x.S                |   5 +-
 arch/powerpc/kernel/head_64.S                 |   7 +-
 arch/powerpc/kernel/head_8xx.S                |   5 +-
 arch/powerpc/kernel/head_book3s_32.S          |  29 +++--
 arch/powerpc/kernel/head_fsl_booke.S          |   5 +-
 arch/powerpc/kernel/misc_64.S                 |   4 +-
 arch/powerpc/kernel/swsusp_32.S               |   5 +-
 arch/powerpc/kernel/vdso/Makefile             |   2 +
 arch/powerpc/kernel/vector.S                  |   4 +-
 arch/powerpc/kvm/book3s_hv_interrupts.S       |   4 +-
 arch/powerpc/kvm/book3s_hv_rmhandlers.S       |  25 +++--
 arch/powerpc/kvm/fpu.S                        |  17 ++-
 arch/powerpc/platforms/52xx/lite5200_sleep.S  |  15 ++-
 arch/x86/Kconfig                              |   1 +
 drivers/crypto/vmx/Makefile                   |   2 +
 kernel/trace/Kconfig                          |   7 ++
 scripts/Makefile.lib                          |   1 +
 tools/objtool/arch/powerpc/Build              |   2 +
 tools/objtool/arch/powerpc/decode.c           | 101 ++++++++++++++++++
 .../arch/powerpc/include/arch/cfi_regs.h      |  11 ++
 tools/objtool/arch/powerpc/include/arch/elf.h |  10 ++
 .../arch/powerpc/include/arch/special.h       |  21 ++++
 tools/objtool/arch/powerpc/special.c          |  19 ++++
 tools/objtool/arch/x86/decode.c               |   5 +
 tools/objtool/arch/x86/include/arch/elf.h     |   2 +
 .../arch/x86/include/arch/endianness.h        |   9 --
 tools/objtool/builtin-check.c                 |  14 +++
 tools/objtool/check.c                         |  53 ++++-----
 tools/objtool/elf.c                           |   8 +-
 tools/objtool/include/objtool/arch.h          |   2 +
 tools/objtool/include/objtool/builtin.h       |   1 +
 tools/objtool/include/objtool/elf.h           |   8 ++
 tools/objtool/include/objtool/endianness.h    |  32 +++---
 tools/objtool/orc_dump.c                      |  11 +-
 tools/objtool/orc_gen.c                       |   4 +-
 tools/objtool/special.c                       |   3 +-
 46 files changed, 418 insertions(+), 107 deletions(-)
 create mode 100644 arch/powerpc/include/asm/asm.h
 create mode 100644 tools/objtool/arch/powerpc/Build
 create mode 100644 tools/objtool/arch/powerpc/decode.c
 create mode 100644 tools/objtool/arch/powerpc/include/arch/cfi_regs.h
 create mode 100644 tools/objtool/arch/powerpc/include/arch/elf.h
 create mode 100644 tools/objtool/arch/powerpc/include/arch/special.h
 create mode 100644 tools/objtool/arch/powerpc/special.c
 delete mode 100644 tools/objtool/arch/x86/include/arch/endianness.h

-- 
2.31.1

[PATCH v4 01/16] powerpc: Fix __WARN_FLAGS() for use with Objtool

[Sathvika Vasireddy]

Commit 1e688dd2a3d675 ("powerpc/bug: Provide better flexibility to
WARN_ON/__WARN_FLAGS() with asm goto") updated __WARN_FLAGS() to use asm
goto, and added a call to 'unreachable()' after the asm goto for optimal
code generation. With CONFIG_OBJTOOL enabled, 'annotate_unreachable()'
statement in 'unreachable()' tries to note down the location of the
subsequent instruction in a separate elf section to aid code flow
analysis. However, on powerpc, this results in gcc emitting a call to a
symbol of size 0. This results in objtool complaining of "unannotated
intra-function call" since the target symbol is not a valid function
call destination.

Objtool wants this annotation for code flow analysis, which we are not
yet enabling on powerpc. As such, expand the call to 'unreachable()' in
__WARN_FLAGS() without annotate_unreachable():
        barrier_before_unreachable();
        __builtin_unreachable();

This still results in optimal code generation for __WARN_FLAGS(), while
getting rid of the objtool warning.

We still need barrier_before_unreachable() to work around gcc bugs 82365
and 106751:
- https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
- https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 arch/powerpc/include/asm/bug.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/bug.h b/arch/powerpc/include/asm/bug.h
index 61a4736355c2..ef42adb44aa3 100644
--- a/arch/powerpc/include/asm/bug.h
+++ b/arch/powerpc/include/asm/bug.h
@@ -99,7 +99,8 @@
 	__label__ __label_warn_on;				\
 								\
 	WARN_ENTRY("twi 31, 0, 0", BUGFLAG_WARNING | (flags), __label_warn_on); \
-	unreachable();						\
+	barrier_before_unreachable();				\
+	__builtin_unreachable();				\
 								\
 __label_warn_on:						\
 	break;							\
-- 
2.31.1

[PATCH v4 02/16] powerpc: Override __ALIGN and __ALIGN_STR macros

[Sathvika Vasireddy]

In a subsequent patch, we would want to annotate powerpc assembly functions
with SYM_FUNC_START_LOCAL macro. This macro depends on __ALIGN macro.

The default expansion of __ALIGN macro is:
        #define __ALIGN      .align 4,0x90

So, override __ALIGN and __ALIGN_STR macros to use the same alignment as
that of the existing _GLOBAL macro. Also, do not pad with 0x90, because
repeated 0x90s are not a nop or trap on powerpc.

Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 arch/powerpc/include/asm/linkage.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/include/asm/linkage.h b/arch/powerpc/include/asm/linkage.h
index b71b9582e754..b88d1d2cf304 100644
--- a/arch/powerpc/include/asm/linkage.h
+++ b/arch/powerpc/include/asm/linkage.h
@@ -4,6 +4,9 @@
 
 #include <asm/types.h>
 
+#define __ALIGN		.align 2
+#define __ALIGN_STR	".align 2"
+
 #ifdef CONFIG_PPC64_ELF_ABI_V1
 #define cond_syscall(x) \
 	asm ("\t.weak " #x "\n\t.set " #x ", sys_ni_syscall\n"		\
-- 
2.31.1

[PATCH v4 03/16] powerpc: Fix objtool unannotated intra-function call warnings

[Sathvika Vasireddy]

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.

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 arch/powerpc/kernel/exceptions-64s.S    |  7 +++++--
 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, 34 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 3d0dc133a9ae..56a31424c8b0 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>
@@ -3075,7 +3076,7 @@ CLOSE_FIXED_SECTION(virt_trampolines);
 USE_TEXT_SECTION()
 
 /* MSR[RI] should be clear because this uses SRR[01] */
-enable_machine_check:
+SYM_FUNC_START_LOCAL(enable_machine_check)
 	mflr	r0
 	bcl	20,31,$+4
 0:	mflr	r3
@@ -3087,9 +3088,10 @@ enable_machine_check:
 	RFI_TO_KERNEL
 1:	mtlr	r0
 	blr
+SYM_FUNC_END(enable_machine_check)
 
 /* 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
@@ -3102,3 +3104,4 @@ 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 cf2c08902c05..10e2d43420d0 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>
@@ -465,7 +466,7 @@ 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
@@ -476,6 +477,7 @@ __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
 	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 fd6d8d3a548e..b36fb89ff718 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
 	/* 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 5cc24d8cce94..929e9ee1b8b1 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>
@@ -186,7 +187,7 @@ 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
@@ -203,6 +204,7 @@ 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@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)
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 7ded202bf995..bc187bb216ac 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@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
-- 
2.31.1

[PATCH v4 04/16] powerpc: Curb objtool unannotated intra-function warnings

[Sathvika Vasireddy]

objtool throws the following unannotated intra-function call warnings:
arch/powerpc/kernel/entry_64.o: warning: objtool: .text+0x4: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0xe64: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0xee4: unannotated intra-function call

Fix these warnings by annotating intra-function calls, using
ANNOTATE_INTRA_FUNCTION_CALL macro, to indicate that the branch targets
are valid.

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 arch/powerpc/kernel/entry_64.S          | 2 ++
 arch/powerpc/kvm/book3s_hv_rmhandlers.S | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 01ace4c56104..fb444bc64f3f 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -14,6 +14,7 @@
  *  code, and exception/interrupt return code for PowerPC.
  */
 
+#include <linux/objtool.h>
 #include <linux/errno.h>
 #include <linux/err.h>
 #include <asm/cache.h>
@@ -73,6 +74,7 @@ flush_branch_caches:
 
 	// Flush the link stack
 	.rept 64
+	ANNOTATE_INTRA_FUNCTION_CALL
 	bl	.+4
 	.endr
 	b	1f
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index bc187bb216ac..20212eb30764 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -11,6 +11,7 @@
  */
 
 #include <linux/linkage.h>
+#include <linux/objtool.h>
 #include <asm/ppc_asm.h>
 #include <asm/code-patching-asm.h>
 #include <asm/kvm_asm.h>
@@ -1523,12 +1524,14 @@ kvm_flush_link_stack:
 
 	/* Flush the link stack. On Power8 it's up to 32 entries in size. */
 	.rept 32
+	ANNOTATE_INTRA_FUNCTION_CALL
 	bl	.+4
 	.endr
 
 	/* And on Power9 it's up to 64. */
 BEGIN_FTR_SECTION
 	.rept 32
+	ANNOTATE_INTRA_FUNCTION_CALL
 	bl	.+4
 	.endr
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
-- 
2.31.1

[PATCH v4 05/16] powerpc: Skip objtool from running on drivers/crypto/vmx/aesp8-ppc.o

[Sathvika Vasireddy]

With objtool enabled, below warnings are seen when trying to build:
drivers/crypto/vmx/aesp8-ppc.o: warning: objtool: aes_p8_set_encrypt_key+0x44: unannotated intra-function call
drivers/crypto/vmx/aesp8-ppc.o: warning: objtool: .text+0x2448: unannotated intra-function call
drivers/crypto/vmx/aesp8-ppc.o: warning: objtool: .text+0x2d68: unannotated intra-function call

Skip objtool from running on drivers/crypto/vmx/aesp8-ppc.o file for the
following reasons:

- Since this file comes from OpenSSL, and since it is a perl file which
  generates a .S file, it may not be the best choice to make too many
  code changes to such files, unless absolutely necessary.

- As far as the objtool --mcount functionality is concerned, we do not
  have to run objtool on this file because there are no calls to
  _mcount.

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 drivers/crypto/vmx/Makefile | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/crypto/vmx/Makefile b/drivers/crypto/vmx/Makefile
index 2560cfea1dec..7b41f0da6807 100644
--- a/drivers/crypto/vmx/Makefile
+++ b/drivers/crypto/vmx/Makefile
@@ -9,3 +9,5 @@ targets += aesp8-ppc.S ghashp8-ppc.S
 
 $(obj)/aesp8-ppc.S $(obj)/ghashp8-ppc.S: $(obj)/%.S: $(src)/%.pl FORCE
 	$(call if_changed,perl)
+
+OBJECT_FILES_NON_STANDARD_aesp8-ppc.o := y
-- 
2.31.1

[PATCH v4 06/16] powerpc: Fix objtool unannotated intra-function call warnings on PPC32

[Sathvika Vasireddy]

From: Christophe Leroy <christophe.leroy@csgroup.eu>

Fix several annotations in assembly files on PPC32.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[Sathvika Vasireddy: Changed subject line from "objtool/powerpc: Activate
objtool on PPC32" to "powerpc: Fix objtool unannotated intra-function call
warnings on PPC32", and removed Kconfig change to enable objtool, as it
is a part of "objtool/powerpc: Enable objtool to be built on ppc" patch in
this series.]
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 arch/powerpc/kernel/cpu_setup_6xx.S          | 26 ++++++++++++------
 arch/powerpc/kernel/cpu_setup_fsl_booke.S    |  8 ++++--
 arch/powerpc/kernel/entry_32.S               |  9 ++++--
 arch/powerpc/kernel/head_40x.S               |  5 +++-
 arch/powerpc/kernel/head_8xx.S               |  5 +++-
 arch/powerpc/kernel/head_book3s_32.S         | 29 ++++++++++++++------
 arch/powerpc/kernel/head_fsl_booke.S         |  5 +++-
 arch/powerpc/kernel/swsusp_32.S              |  5 +++-
 arch/powerpc/kvm/fpu.S                       | 17 ++++++++----
 arch/powerpc/platforms/52xx/lite5200_sleep.S | 15 +++++++---
 10 files changed, 89 insertions(+), 35 deletions(-)

diff --git a/arch/powerpc/kernel/cpu_setup_6xx.S b/arch/powerpc/kernel/cpu_setup_6xx.S
index f8b5ff64b604..f29ce3dd6140 100644
--- a/arch/powerpc/kernel/cpu_setup_6xx.S
+++ b/arch/powerpc/kernel/cpu_setup_6xx.S
@@ -4,6 +4,8 @@
  *    Copyright (C) 2003 Benjamin Herrenschmidt (benh@kernel.crashing.org)
  */
 
+#include <linux/linkage.h>
+
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/cputable.h>
@@ -81,7 +83,7 @@ _GLOBAL(__setup_cpu_745x)
 	blr
 
 /* Enable caches for 603's, 604, 750 & 7400 */
-setup_common_caches:
+SYM_FUNC_START_LOCAL(setup_common_caches)
 	mfspr	r11,SPRN_HID0
 	andi.	r0,r11,HID0_DCE
 	ori	r11,r11,HID0_ICE|HID0_DCE
@@ -95,11 +97,12 @@ setup_common_caches:
 	sync
 	isync
 	blr
+SYM_FUNC_END(setup_common_caches)
 
 /* 604, 604e, 604ev, ...
  * Enable superscalar execution & branch history table
  */
-setup_604_hid0:
+SYM_FUNC_START_LOCAL(setup_604_hid0)
 	mfspr	r11,SPRN_HID0
 	ori	r11,r11,HID0_SIED|HID0_BHTE
 	ori	r8,r11,HID0_BTCD
@@ -110,6 +113,7 @@ setup_604_hid0:
 	sync
 	isync
 	blr
+SYM_FUNC_END(setup_604_hid0)
 
 /* 7400 <= rev 2.7 and 7410 rev = 1.0 suffer from some
  * erratas we work around here.
@@ -125,13 +129,14 @@ setup_604_hid0:
  * needed once we have applied workaround #5 (though it's
  * not set by Apple's firmware at least).
  */
-setup_7400_workarounds:
+SYM_FUNC_START_LOCAL(setup_7400_workarounds)
 	mfpvr	r3
 	rlwinm	r3,r3,0,20,31
 	cmpwi	0,r3,0x0207
 	ble	1f
 	blr
-setup_7410_workarounds:
+SYM_FUNC_END(setup_7400_workarounds)
+SYM_FUNC_START_LOCAL(setup_7410_workarounds)
 	mfpvr	r3
 	rlwinm	r3,r3,0,20,31
 	cmpwi	0,r3,0x0100
@@ -151,6 +156,7 @@ setup_7410_workarounds:
 	sync
 	isync
 	blr
+SYM_FUNC_END(setup_7410_workarounds)
 
 /* 740/750/7400/7410
  * Enable Store Gathering (SGE), Address Broadcast (ABE),
@@ -158,7 +164,7 @@ setup_7410_workarounds:
  * Dynamic Power Management (DPM), Speculative (SPD)
  * Clear Instruction cache throttling (ICTC)
  */
-setup_750_7400_hid0:
+SYM_FUNC_START_LOCAL(setup_750_7400_hid0)
 	mfspr	r11,SPRN_HID0
 	ori	r11,r11,HID0_SGE | HID0_ABE | HID0_BHTE | HID0_BTIC
 	oris	r11,r11,HID0_DPM@h
@@ -177,12 +183,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_NO_DPM)
 	sync
 	isync
 	blr
+SYM_FUNC_END(setup_750_7400_hid0)
 
 /* 750cx specific
  * Looks like we have to disable NAP feature for some PLL settings...
  * (waiting for confirmation)
  */
-setup_750cx:
+SYM_FUNC_START_LOCAL(setup_750cx)
 	mfspr	r10, SPRN_HID1
 	rlwinm	r10,r10,4,28,31
 	cmpwi	cr0,r10,7
@@ -196,11 +203,13 @@ setup_750cx:
 	andc	r6,r6,r7
 	stw	r6,CPU_SPEC_FEATURES(r4)
 	blr
+SYM_FUNC_END(setup_750cx)
 
 /* 750fx specific
  */
-setup_750fx:
+SYM_FUNC_START_LOCAL(setup_750fx)
 	blr
+SYM_FUNC_END(setup_750fx)
 
 /* MPC 745x
  * Enable Store Gathering (SGE), Branch Folding (FOLD)
@@ -212,7 +221,7 @@ setup_750fx:
  * Clear Instruction cache throttling (ICTC)
  * Enable L2 HW prefetch
  */
-setup_745x_specifics:
+SYM_FUNC_START_LOCAL(setup_745x_specifics)
 	/* We check for the presence of an L3 cache setup by
 	 * the firmware. If any, we disable NAP capability as
 	 * it's known to be bogus on rev 2.1 and earlier
@@ -270,6 +279,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_NO_DPM)
 	sync
 	isync
 	blr
+SYM_FUNC_END(setup_745x_specifics)
 
 /*
  * Initialize the FPU registers. This is needed to work around an errata
diff --git a/arch/powerpc/kernel/cpu_setup_fsl_booke.S b/arch/powerpc/kernel/cpu_setup_fsl_booke.S
index 4bf33f1b4193..f573a4f3bbe6 100644
--- a/arch/powerpc/kernel/cpu_setup_fsl_booke.S
+++ b/arch/powerpc/kernel/cpu_setup_fsl_booke.S
@@ -8,6 +8,8 @@
  * Benjamin Herrenschmidt <benh@kernel.crashing.org>
  */
 
+#include <linux/linkage.h>
+
 #include <asm/page.h>
 #include <asm/processor.h>
 #include <asm/cputable.h>
@@ -274,7 +276,7 @@ _GLOBAL(flush_dcache_L1)
 
 	blr
 
-has_L2_cache:
+SYM_FUNC_START_LOCAL(has_L2_cache)
 	/* skip L2 cache on P2040/P2040E as they have no L2 cache */
 	mfspr	r3, SPRN_SVR
 	/* shift right by 8 bits and clear E bit of SVR */
@@ -290,9 +292,10 @@ has_L2_cache:
 1:
 	li	r3, 0
 	blr
+SYM_FUNC_END(has_L2_cache)
 
 /* flush backside L2 cache */
-flush_backside_L2_cache:
+SYM_FUNC_START_LOCAL(flush_backside_L2_cache)
 	mflr	r10
 	bl	has_L2_cache
 	mtlr	r10
@@ -313,6 +316,7 @@ flush_backside_L2_cache:
 	bne	1b
 2:
 	blr
+SYM_FUNC_END(flush_backside_L2_cache)
 
 _GLOBAL(cpu_down_flush_e500v2)
 	mflr r0
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 1d599df6f169..f8480d88509f 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -18,6 +18,8 @@
 #include <linux/err.h>
 #include <linux/sys.h>
 #include <linux/threads.h>
+#include <linux/linkage.h>
+
 #include <asm/reg.h>
 #include <asm/page.h>
 #include <asm/mmu.h>
@@ -74,17 +76,18 @@ _ASM_NOKPROBE_SYMBOL(prepare_transfer_to_handler)
 #endif /* CONFIG_PPC_BOOK3S_32 || CONFIG_E500 */
 
 #if defined(CONFIG_PPC_KUEP) && defined(CONFIG_PPC_BOOK3S_32)
-	.globl	__kuep_lock
-__kuep_lock:
+SYM_FUNC_START(__kuep_lock)
 	lwz	r9, THREAD+THSR0(r2)
 	update_user_segments_by_4 r9, r10, r11, r12
 	blr
+SYM_FUNC_END(__kuep_lock)
 
-__kuep_unlock:
+SYM_FUNC_START_LOCAL(__kuep_unlock)
 	lwz	r9, THREAD+THSR0(r2)
 	rlwinm  r9,r9,0,~SR_NX
 	update_user_segments_by_4 r9, r10, r11, r12
 	blr
+SYM_FUNC_END(__kuep_unlock)
 
 .macro	kuep_lock
 	bl	__kuep_lock
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 088f500896c7..9110fe9d6747 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -28,6 +28,8 @@
 #include <linux/init.h>
 #include <linux/pgtable.h>
 #include <linux/sizes.h>
+#include <linux/linkage.h>
+
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/mmu.h>
@@ -662,7 +664,7 @@ start_here:
  * kernel initialization.  This maps the first 32 MBytes of memory 1:1
  * virtual to physical and more importantly sets the cache mode.
  */
-initial_mmu:
+SYM_FUNC_START_LOCAL(initial_mmu)
 	tlbia			/* Invalidate all TLB entries */
 	isync
 
@@ -711,6 +713,7 @@ initial_mmu:
 	mtspr	SPRN_EVPR,r0
 
 	blr
+SYM_FUNC_END(initial_mmu)
 
 _GLOBAL(abort)
         mfspr   r13,SPRN_DBCR0
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 0b05f2be66b9..c94ed5a08c93 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -18,6 +18,8 @@
 #include <linux/magic.h>
 #include <linux/pgtable.h>
 #include <linux/sizes.h>
+#include <linux/linkage.h>
+
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/mmu.h>
@@ -625,7 +627,7 @@ start_here:
  * 24 Mbytes of data, and the 512k IMMR space.  Anything not covered by
  * these mappings is mapped by page tables.
  */
-initial_mmu:
+SYM_FUNC_START_LOCAL(initial_mmu)
 	li	r8, 0
 	mtspr	SPRN_MI_CTR, r8		/* remove PINNED ITLB entries */
 	lis	r10, MD_TWAM@h
@@ -686,6 +688,7 @@ initial_mmu:
 #endif
 	mtspr	SPRN_DER, r8
 	blr
+SYM_FUNC_END(initial_mmu)
 
 _GLOBAL(mmu_pin_tlb)
 	lis	r9, (1f - PAGE_OFFSET)@h
diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S
index 519b60695167..4af12447dc0b 100644
--- a/arch/powerpc/kernel/head_book3s_32.S
+++ b/arch/powerpc/kernel/head_book3s_32.S
@@ -18,6 +18,8 @@
 
 #include <linux/init.h>
 #include <linux/pgtable.h>
+#include <linux/linkage.h>
+
 #include <asm/reg.h>
 #include <asm/page.h>
 #include <asm/mmu.h>
@@ -877,7 +879,7 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
  * Load stuff into the MMU.  Intended to be called with
  * IR=0 and DR=0.
  */
-early_hash_table:
+SYM_FUNC_START_LOCAL(early_hash_table)
 	sync			/* Force all PTE updates to finish */
 	isync
 	tlbia			/* Clear all TLB entries */
@@ -888,8 +890,9 @@ early_hash_table:
 	ori	r6, r6, 3	/* 256kB table */
 	mtspr	SPRN_SDR1, r6
 	blr
+SYM_FUNC_END(early_hash_table)
 
-load_up_mmu:
+SYM_FUNC_START_LOCAL(load_up_mmu)
 	sync			/* Force all PTE updates to finish */
 	isync
 	tlbia			/* Clear all TLB entries */
@@ -918,6 +921,7 @@ BEGIN_MMU_FTR_SECTION
 	LOAD_BAT(7,r3,r4,r5)
 END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
 	blr
+SYM_FUNC_END(load_up_mmu)
 
 _GLOBAL(load_segment_registers)
 	li	r0, NUM_USER_SEGMENTS /* load up user segment register values */
@@ -1028,7 +1032,7 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
  * this makes sure it's done.
  *  -- Cort
  */
-clear_bats:
+SYM_FUNC_START_LOCAL(clear_bats)
 	li	r10,0
 
 	mtspr	SPRN_DBAT0U,r10
@@ -1072,6 +1076,7 @@ BEGIN_MMU_FTR_SECTION
 	mtspr	SPRN_IBAT7L,r10
 END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
 	blr
+SYM_FUNC_END(clear_bats)
 
 _GLOBAL(update_bats)
 	lis	r4, 1f@h
@@ -1108,15 +1113,16 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
 	mtspr	SPRN_SRR1, r6
 	rfi
 
-flush_tlbs:
+SYM_FUNC_START_LOCAL(flush_tlbs)
 	lis	r10, 0x40
 1:	addic.	r10, r10, -0x1000
 	tlbie	r10
 	bgt	1b
 	sync
 	blr
+SYM_FUNC_END(flush_tlbs)
 
-mmu_off:
+SYM_FUNC_START_LOCAL(mmu_off)
  	addi	r4, r3, __after_mmu_off - _start
 	mfmsr	r3
 	andi.	r0,r3,MSR_DR|MSR_IR		/* MMU enabled? */
@@ -1128,9 +1134,10 @@ mmu_off:
 	mtspr	SPRN_SRR1,r3
 	sync
 	rfi
+SYM_FUNC_END(mmu_off)
 
 /* We use one BAT to map up to 256M of RAM at _PAGE_OFFSET */
-initial_bats:
+SYM_FUNC_START_LOCAL(initial_bats)
 	lis	r11,PAGE_OFFSET@h
 	tophys(r8,r11)
 #ifdef CONFIG_SMP
@@ -1146,9 +1153,10 @@ initial_bats:
 	mtspr	SPRN_IBAT0U,r11
 	isync
 	blr
+SYM_FUNC_END(initial_bats)
 
 #ifdef CONFIG_BOOTX_TEXT
-setup_disp_bat:
+SYM_FUNC_START_LOCAL(setup_disp_bat)
 	/*
 	 * setup the display bat prepared for us in prom.c
 	 */
@@ -1164,10 +1172,11 @@ setup_disp_bat:
 	mtspr	SPRN_DBAT3L,r8
 	mtspr	SPRN_DBAT3U,r11
 	blr
+SYM_FUNC_END(setup_disp_bat)
 #endif /* CONFIG_BOOTX_TEXT */
 
 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
-setup_cpm_bat:
+SYM_FUNC_START_LOCAL(setup_cpm_bat)
 	lis	r8, 0xf000
 	ori	r8, r8,	0x002a
 	mtspr	SPRN_DBAT1L, r8
@@ -1177,10 +1186,11 @@ setup_cpm_bat:
 	mtspr	SPRN_DBAT1U, r11
 
 	blr
+SYM_FUNC_END(setup_cpm_bat)
 #endif
 
 #ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
-setup_usbgecko_bat:
+SYM_FUNC_START_LOCAL(setup_usbgecko_bat)
 	/* prepare a BAT for early io */
 #if defined(CONFIG_GAMECUBE)
 	lis	r8, 0x0c00
@@ -1199,6 +1209,7 @@ setup_usbgecko_bat:
 	mtspr	SPRN_DBAT1L, r8
 	mtspr	SPRN_DBAT1U, r11
 	blr
+SYM_FUNC_END(setup_usbgecko_bat)
 #endif
 
 	.data
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index f0db4f52bc00..744b096857a1 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -29,6 +29,8 @@
 #include <linux/init.h>
 #include <linux/threads.h>
 #include <linux/pgtable.h>
+#include <linux/linkage.h>
+
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/mmu.h>
@@ -885,7 +887,7 @@ KernelSPE:
  * Translate the effec addr in r3 to phys addr. The phys addr will be put
  * into r3(higher 32bit) and r4(lower 32bit)
  */
-get_phys_addr:
+SYM_FUNC_START_LOCAL(get_phys_addr)
 	mfmsr	r8
 	mfspr	r9,SPRN_PID
 	rlwinm	r9,r9,16,0x3fff0000	/* turn PID into MAS6[SPID] */
@@ -907,6 +909,7 @@ get_phys_addr:
 	mfspr	r3,SPRN_MAS7
 #endif
 	blr
+SYM_FUNC_END(get_phys_addr)
 
 /*
  * Global functions
diff --git a/arch/powerpc/kernel/swsusp_32.S b/arch/powerpc/kernel/swsusp_32.S
index e0cbd63007f2..ffb79326483c 100644
--- a/arch/powerpc/kernel/swsusp_32.S
+++ b/arch/powerpc/kernel/swsusp_32.S
@@ -1,5 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 #include <linux/threads.h>
+#include <linux/linkage.h>
+
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/cputable.h>
@@ -400,7 +402,7 @@ _ASM_NOKPROBE_SYMBOL(swsusp_arch_resume)
 /* FIXME:This construct is actually not useful since we don't shut
  * down the instruction MMU, we could just flip back MSR-DR on.
  */
-turn_on_mmu:
+SYM_FUNC_START_LOCAL(turn_on_mmu)
 	mflr	r4
 	mtsrr0	r4
 	mtsrr1	r3
@@ -408,4 +410,5 @@ turn_on_mmu:
 	isync
 	rfi
 _ASM_NOKPROBE_SYMBOL(turn_on_mmu)
+SYM_FUNC_END(turn_on_mmu)
 
diff --git a/arch/powerpc/kvm/fpu.S b/arch/powerpc/kvm/fpu.S
index 315c94946bad..b68e7f26a81f 100644
--- a/arch/powerpc/kvm/fpu.S
+++ b/arch/powerpc/kvm/fpu.S
@@ -6,6 +6,8 @@
  */
 
 #include <linux/pgtable.h>
+#include <linux/linkage.h>
+
 #include <asm/reg.h>
 #include <asm/page.h>
 #include <asm/mmu.h>
@@ -110,18 +112,22 @@ FPS_THREE_IN(fsel)
  * R8 = (double*)&param3 [load_three]
  * LR = instruction call function
  */
-fpd_load_three:
+SYM_FUNC_START_LOCAL(fpd_load_three)
 	lfd	2,0(r8)			/* load param3 */
-fpd_load_two:
+SYM_FUNC_START_LOCAL(fpd_load_two)
 	lfd	1,0(r7)			/* load param2 */
-fpd_load_one:
+SYM_FUNC_START_LOCAL(fpd_load_one)
 	lfd	0,0(r6)			/* load param1 */
-fpd_load_none:
+SYM_FUNC_START_LOCAL(fpd_load_none)
 	lfd	3,0(r3)			/* load up fpscr value */
 	MTFSF_L(3)
 	lwz	r6, 0(r4)		/* load cr */
 	mtcr	r6
 	blr
+SYM_FUNC_END(fpd_load_none)
+SYM_FUNC_END(fpd_load_one)
+SYM_FUNC_END(fpd_load_two)
+SYM_FUNC_END(fpd_load_three)
 
 /*
  * End of double instruction processing
@@ -131,13 +137,14 @@ fpd_load_none:
  * R5 = (double*)&result
  * LR = caller of instruction call function
  */
-fpd_return:
+SYM_FUNC_START_LOCAL(fpd_return)
 	mfcr	r6
 	stfd	0,0(r5)			/* save result */
 	mffs	0
 	stfd	0,0(r3)			/* save new fpscr value */
 	stw	r6,0(r4)		/* save new cr value */
 	blr
+SYM_FUNC_END(fpd_return)
 
 /*
  * Double operation with no input operand
diff --git a/arch/powerpc/platforms/52xx/lite5200_sleep.S b/arch/powerpc/platforms/52xx/lite5200_sleep.S
index afee8b1515a8..0b12647e7b42 100644
--- a/arch/powerpc/platforms/52xx/lite5200_sleep.S
+++ b/arch/powerpc/platforms/52xx/lite5200_sleep.S
@@ -1,4 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/linkage.h>
+
 #include <asm/reg.h>
 #include <asm/ppc_asm.h>
 #include <asm/processor.h>
@@ -178,7 +180,8 @@ sram_code:
 
 
 	/* local udelay in sram is needed */
-  udelay: /* r11 - tb_ticks_per_usec, r12 - usecs, overwrites r13 */
+SYM_FUNC_START_LOCAL(udelay)
+	/* r11 - tb_ticks_per_usec, r12 - usecs, overwrites r13 */
 	mullw	r12, r12, r11
 	mftb	r13	/* start */
 	add	r12, r13, r12 /* end */
@@ -187,6 +190,7 @@ sram_code:
 	cmp	cr0, r13, r12
 	blt	1b
 	blr
+SYM_FUNC_END(udelay)
 
 sram_code_end:
 
@@ -271,7 +275,7 @@ _ASM_NOKPROBE_SYMBOL(lite5200_wakeup)
 	SAVE_SR(n+2, addr+2);	\
 	SAVE_SR(n+3, addr+3);
 
-save_regs:
+SYM_FUNC_START_LOCAL(save_regs)
 	stw	r0, 0(r4)
 	stw	r1, 0x4(r4)
 	stw	r2, 0x8(r4)
@@ -317,6 +321,7 @@ save_regs:
 	SAVE_SPRN(TBRU,  0x5b)
 
 	blr
+SYM_FUNC_END(save_regs)
 
 
 /* restore registers */
@@ -336,7 +341,7 @@ save_regs:
 	LOAD_SR(n+2, addr+2);	\
 	LOAD_SR(n+3, addr+3);
 
-restore_regs:
+SYM_FUNC_START_LOCAL(restore_regs)
 	lis	r4, registers@h
 	ori	r4, r4, registers@l
 
@@ -393,6 +398,7 @@ restore_regs:
 
 	blr
 _ASM_NOKPROBE_SYMBOL(restore_regs)
+SYM_FUNC_END(restore_regs)
 
 
 
@@ -403,7 +409,7 @@ _ASM_NOKPROBE_SYMBOL(restore_regs)
  * Flush data cache
  * Do this by just reading lots of stuff into the cache.
  */
-flush_data_cache:
+SYM_FUNC_START_LOCAL(flush_data_cache)
 	lis	r3,CONFIG_KERNEL_START@h
 	ori	r3,r3,CONFIG_KERNEL_START@l
 	li	r4,NUM_CACHE_LINES
@@ -413,3 +419,4 @@ flush_data_cache:
 	addi	r3,r3,L1_CACHE_BYTES	/* Next line, please */
 	bdnz	1b
 	blr
+SYM_FUNC_END(flush_data_cache)
-- 
2.31.1

[PATCH v4 07/16] powerpc: Skip objtool from running on VDSO files

[Sathvika Vasireddy]

Do not run objtool on VDSO files, by using OBJECT_FILES_NON_STANDARD.

Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 arch/powerpc/kernel/vdso/Makefile | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/kernel/vdso/Makefile b/arch/powerpc/kernel/vdso/Makefile
index a2e7b0ce5b19..6a977b0d8ffc 100644
--- a/arch/powerpc/kernel/vdso/Makefile
+++ b/arch/powerpc/kernel/vdso/Makefile
@@ -102,3 +102,5 @@ quiet_cmd_vdso64ld_and_check = VDSO64L $@
       cmd_vdso64ld_and_check = $(VDSOCC) $(c_flags) $(CC64FLAGS) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) -z noexecstack ; $(cmd_vdso_check)
 quiet_cmd_vdso64as = VDSO64A $@
       cmd_vdso64as = $(VDSOCC) $(a_flags) $(CC64FLAGS) $(AS64FLAGS) -c -o $@ $<
+
+OBJECT_FILES_NON_STANDARD := y
-- 
2.31.1

[PATCH v4 08/16] objtool: Fix SEGFAULT

[Sathvika Vasireddy]

From: Christophe Leroy <christophe.leroy@csgroup.eu>

find_insn() will return NULL in case of failure. Check insn in order
to avoid a kernel Oops for NULL pointer dereference.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 tools/objtool/check.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index e55fdf952a3a..fe935f19447b 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -207,7 +207,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		return false;
 
 	insn = find_insn(file, func->sec, func->offset);
-	if (!insn->func)
+	if (!insn || !insn->func)
 		return false;
 
 	func_for_each_insn(file, func, insn) {
-- 
2.31.1

[PATCH v4 09/16] objtool: Use target file endianness instead of a compiled constant

[Sathvika Vasireddy]

From: Christophe Leroy <christophe.leroy@csgroup.eu>

Some architectures like powerpc support both endianness, it's
therefore not possible to fix the endianness via arch/endianness.h
because there is no easy way to get the target endianness at
build time.

Use the endianness recorded in the file objtool is working on.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 .../arch/x86/include/arch/endianness.h        |  9 ------
 tools/objtool/check.c                         |  2 +-
 tools/objtool/include/objtool/endianness.h    | 32 +++++++++----------
 tools/objtool/orc_dump.c                      | 11 +++++--
 tools/objtool/orc_gen.c                       |  4 +--
 tools/objtool/special.c                       |  3 +-
 6 files changed, 30 insertions(+), 31 deletions(-)
 delete mode 100644 tools/objtool/arch/x86/include/arch/endianness.h

diff --git a/tools/objtool/arch/x86/include/arch/endianness.h b/tools/objtool/arch/x86/include/arch/endianness.h
deleted file mode 100644
index 7c362527da20..000000000000
--- a/tools/objtool/arch/x86/include/arch/endianness.h
+++ /dev/null
@@ -1,9 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-#ifndef _ARCH_ENDIANNESS_H
-#define _ARCH_ENDIANNESS_H
-
-#include <endian.h>
-
-#define __TARGET_BYTE_ORDER __LITTLE_ENDIAN
-
-#endif /* _ARCH_ENDIANNESS_H */
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index fe935f19447b..c36e7a020d80 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2077,7 +2077,7 @@ static int read_unwind_hints(struct objtool_file *file)
 			return -1;
 		}
 
-		cfi.cfa.offset = bswap_if_needed(hint->sp_offset);
+		cfi.cfa.offset = bswap_if_needed(file->elf, hint->sp_offset);
 		cfi.type = hint->type;
 		cfi.end = hint->end;
 
diff --git a/tools/objtool/include/objtool/endianness.h b/tools/objtool/include/objtool/endianness.h
index 10241341eff3..4d2aa9b0fe2f 100644
--- a/tools/objtool/include/objtool/endianness.h
+++ b/tools/objtool/include/objtool/endianness.h
@@ -2,33 +2,33 @@
 #ifndef _OBJTOOL_ENDIANNESS_H
 #define _OBJTOOL_ENDIANNESS_H
 
-#include <arch/endianness.h>
 #include <linux/kernel.h>
 #include <endian.h>
-
-#ifndef __TARGET_BYTE_ORDER
-#error undefined arch __TARGET_BYTE_ORDER
-#endif
-
-#if __BYTE_ORDER != __TARGET_BYTE_ORDER
-#define __NEED_BSWAP 1
-#else
-#define __NEED_BSWAP 0
-#endif
+#include <objtool/elf.h>
 
 /*
- * Does a byte swap if target endianness doesn't match the host, i.e. cross
+ * Does a byte swap if target file endianness doesn't match the host, i.e. cross
  * compilation for little endian on big endian and vice versa.
  * To be used for multi-byte values conversion, which are read from / about
  * to be written to a target native endianness ELF file.
  */
-#define bswap_if_needed(val)						\
+static inline bool need_bswap(struct elf *elf)
+{
+	return (__BYTE_ORDER == __LITTLE_ENDIAN) ^
+	       (elf->ehdr.e_ident[EI_DATA] == ELFDATA2LSB);
+}
+
+#define bswap_if_needed(elf, val)					\
 ({									\
 	__typeof__(val) __ret;						\
+	bool __need_bswap = need_bswap(elf);				\
 	switch (sizeof(val)) {						\
-	case 8: __ret = __NEED_BSWAP ? bswap_64(val) : (val); break;	\
-	case 4: __ret = __NEED_BSWAP ? bswap_32(val) : (val); break;	\
-	case 2: __ret = __NEED_BSWAP ? bswap_16(val) : (val); break;	\
+	case 8:								\
+		__ret = __need_bswap ? bswap_64(val) : (val); break;	\
+	case 4:								\
+		__ret = __need_bswap ? bswap_32(val) : (val); break;	\
+	case 2:								\
+		__ret = __need_bswap ? bswap_16(val) : (val); break;	\
 	default:							\
 		BUILD_BUG(); break;					\
 	}								\
diff --git a/tools/objtool/orc_dump.c b/tools/objtool/orc_dump.c
index f5a8508c42d6..4f1211fec82c 100644
--- a/tools/objtool/orc_dump.c
+++ b/tools/objtool/orc_dump.c
@@ -76,6 +76,7 @@ int orc_dump(const char *_objname)
 	GElf_Rela rela;
 	GElf_Sym sym;
 	Elf_Data *data, *symtab = NULL, *rela_orc_ip = NULL;
+	struct elf dummy_elf = {};
 
 
 	objname = _objname;
@@ -94,6 +95,12 @@ int orc_dump(const char *_objname)
 		return -1;
 	}
 
+	if (!elf64_getehdr(elf)) {
+		WARN_ELF("elf64_getehdr");
+		return -1;
+	}
+	memcpy(&dummy_elf.ehdr, elf64_getehdr(elf), sizeof(dummy_elf.ehdr));
+
 	if (elf_getshdrnum(elf, &nr_sections)) {
 		WARN_ELF("elf_getshdrnum");
 		return -1;
@@ -198,11 +205,11 @@ int orc_dump(const char *_objname)
 
 		printf(" sp:");
 
-		print_reg(orc[i].sp_reg, bswap_if_needed(orc[i].sp_offset));
+		print_reg(orc[i].sp_reg, bswap_if_needed(&dummy_elf, orc[i].sp_offset));
 
 		printf(" bp:");
 
-		print_reg(orc[i].bp_reg, bswap_if_needed(orc[i].bp_offset));
+		print_reg(orc[i].bp_reg, bswap_if_needed(&dummy_elf, orc[i].bp_offset));
 
 		printf(" type:%s end:%d\n",
 		       orc_type_name(orc[i].type), orc[i].end);
diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c
index dd3c64af9db2..1f22b7ebae58 100644
--- a/tools/objtool/orc_gen.c
+++ b/tools/objtool/orc_gen.c
@@ -97,8 +97,8 @@ static int write_orc_entry(struct elf *elf, struct section *orc_sec,
 	/* populate ORC data */
 	orc = (struct orc_entry *)orc_sec->data->d_buf + idx;
 	memcpy(orc, o, sizeof(*orc));
-	orc->sp_offset = bswap_if_needed(orc->sp_offset);
-	orc->bp_offset = bswap_if_needed(orc->bp_offset);
+	orc->sp_offset = bswap_if_needed(elf, orc->sp_offset);
+	orc->bp_offset = bswap_if_needed(elf, orc->bp_offset);
 
 	/* populate reloc for ip */
 	if (elf_add_reloc_to_insn(elf, ip_sec, idx * sizeof(int), R_X86_64_PC32,
diff --git a/tools/objtool/special.c b/tools/objtool/special.c
index e2223dd91c37..9c8d827f69af 100644
--- a/tools/objtool/special.c
+++ b/tools/objtool/special.c
@@ -87,7 +87,8 @@ static int get_alt_entry(struct elf *elf, struct special_entry *entry,
 	if (entry->feature) {
 		unsigned short feature;
 
-		feature = bswap_if_needed(*(unsigned short *)(sec->data->d_buf +
+		feature = bswap_if_needed(elf,
+					  *(unsigned short *)(sec->data->d_buf +
 							      offset +
 							      entry->feature));
 		arch_handle_alternative(feature, alt);
-- 
2.31.1

[PATCH v4 10/16] objtool: Use target file class size instead of a compiled constant

[Sathvika Vasireddy]

From: Christophe Leroy <christophe.leroy@csgroup.eu>

In order to allow using objtool on cross-built kernels,
determine size of long from elf data instead of using
sizeof(long) at build time.

For the time being this covers only mcount.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[Sathvika Vasireddy: Rename variable "size" to "addrsize" and function
"elf_class_size()" to "elf_class_addrsize()", and modify
create_mcount_loc_sections() function to follow reverse christmas tree
format to order local variable declarations.]
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 tools/objtool/check.c               | 18 ++++++++++--------
 tools/objtool/elf.c                 |  8 ++++++--
 tools/objtool/include/objtool/elf.h |  8 ++++++++
 3 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index c36e7a020d80..738de23cb9e8 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -852,9 +852,9 @@ static int create_ibt_endbr_seal_sections(struct objtool_file *file)
 
 static int create_mcount_loc_sections(struct objtool_file *file)
 {
-	struct section *sec;
-	unsigned long *loc;
+	int addrsize = elf_class_addrsize(file->elf);
 	struct instruction *insn;
+	struct section *sec;
 	int idx;
 
 	sec = find_section_by_name(file->elf, "__mcount_loc");
@@ -871,23 +871,25 @@ static int create_mcount_loc_sections(struct objtool_file *file)
 	list_for_each_entry(insn, &file->mcount_loc_list, call_node)
 		idx++;
 
-	sec = elf_create_section(file->elf, "__mcount_loc", 0, sizeof(unsigned long), idx);
+	sec = elf_create_section(file->elf, "__mcount_loc", 0, addrsize, idx);
 	if (!sec)
 		return -1;
 
+	sec->sh.sh_addralign = addrsize;
+
 	idx = 0;
 	list_for_each_entry(insn, &file->mcount_loc_list, call_node) {
+		void *loc;
 
-		loc = (unsigned long *)sec->data->d_buf + idx;
-		memset(loc, 0, sizeof(unsigned long));
+		loc = sec->data->d_buf + idx;
+		memset(loc, 0, addrsize);
 
-		if (elf_add_reloc_to_insn(file->elf, sec,
-					  idx * sizeof(unsigned long),
+		if (elf_add_reloc_to_insn(file->elf, sec, idx,
 					  R_X86_64_64,
 					  insn->sec, insn->offset))
 			return -1;
 
-		idx++;
+		idx += addrsize;
 	}
 
 	return 0;
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index c25e957c1e52..40c6d53b081f 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -1124,6 +1124,7 @@ static struct section *elf_create_rela_reloc_section(struct elf *elf, struct sec
 {
 	char *relocname;
 	struct section *sec;
+	int addrsize = elf_class_addrsize(elf);
 
 	relocname = malloc(strlen(base->name) + strlen(".rela") + 1);
 	if (!relocname) {
@@ -1133,7 +1134,10 @@ static struct section *elf_create_rela_reloc_section(struct elf *elf, struct sec
 	strcpy(relocname, ".rela");
 	strcat(relocname, base->name);
 
-	sec = elf_create_section(elf, relocname, 0, sizeof(GElf_Rela), 0);
+	if (addrsize == sizeof(u32))
+		sec = elf_create_section(elf, relocname, 0, sizeof(Elf32_Rela), 0);
+	else
+		sec = elf_create_section(elf, relocname, 0, sizeof(GElf_Rela), 0);
 	free(relocname);
 	if (!sec)
 		return NULL;
@@ -1142,7 +1146,7 @@ static struct section *elf_create_rela_reloc_section(struct elf *elf, struct sec
 	sec->base = base;
 
 	sec->sh.sh_type = SHT_RELA;
-	sec->sh.sh_addralign = 8;
+	sec->sh.sh_addralign = addrsize;
 	sec->sh.sh_link = find_section_by_name(elf, ".symtab")->idx;
 	sec->sh.sh_info = base->idx;
 	sec->sh.sh_flags = SHF_INFO_LINK;
diff --git a/tools/objtool/include/objtool/elf.h b/tools/objtool/include/objtool/elf.h
index 16f4067b82ae..78b3aa2e546d 100644
--- a/tools/objtool/include/objtool/elf.h
+++ b/tools/objtool/include/objtool/elf.h
@@ -142,6 +142,14 @@ static inline bool has_multiple_files(struct elf *elf)
 	return elf->num_files > 1;
 }
 
+static inline int elf_class_addrsize(struct elf *elf)
+{
+	if (elf->ehdr.e_ident[EI_CLASS] == ELFCLASS32)
+		return sizeof(u32);
+	else
+		return sizeof(u64);
+}
+
 struct elf *elf_open_read(const char *name, int flags);
 struct section *elf_create_section(struct elf *elf, const char *name, unsigned int sh_flags, size_t entsize, int nr);
 
-- 
2.31.1

[PATCH v4 11/16] objtool: Add --mnop as an option to --mcount

[Sathvika Vasireddy]

Some architectures (powerpc) may not support ftrace locations being nop'ed
out at build time. Introduce CONFIG_HAVE_OBJTOOL_NOP_MCOUNT for objtool, as
a means for architectures to enable nop'ing of ftrace locations. Add --mnop
as an option to objtool --mcount, to indicate support for the same.

Also, make sure that --mnop can be passed as an option to objtool only when
--mcount is passed.

Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 Makefile                                |  4 +++-
 arch/x86/Kconfig                        |  1 +
 kernel/trace/Kconfig                    |  7 +++++++
 scripts/Makefile.lib                    |  1 +
 tools/objtool/builtin-check.c           | 14 ++++++++++++++
 tools/objtool/check.c                   | 19 ++++++++++---------
 tools/objtool/include/objtool/builtin.h |  1 +
 7 files changed, 37 insertions(+), 10 deletions(-)

diff --git a/Makefile b/Makefile
index a5e9d9388649..b2230ad14748 100644
--- a/Makefile
+++ b/Makefile
@@ -857,7 +857,9 @@ ifdef CONFIG_FTRACE_MCOUNT_USE_CC
   endif
 endif
 ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
-  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
+  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
+    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
+  endif
 endif
 ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
   ifdef CONFIG_HAVE_C_RECORDMCOUNT
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f9920f1341c8..2a79a05c4402 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -189,6 +189,7 @@ config X86
 	select HAVE_CONTEXT_TRACKING_USER_OFFSTACK	if HAVE_CONTEXT_TRACKING_USER
 	select HAVE_C_RECORDMCOUNT
 	select HAVE_OBJTOOL_MCOUNT		if HAVE_OBJTOOL
+	select HAVE_OBJTOOL_NOP_MCOUNT		if HAVE_OBJTOOL_MCOUNT
 	select HAVE_BUILDTIME_MCOUNT_SORT
 	select HAVE_DEBUG_KMEMLEAK
 	select HAVE_DMA_CONTIGUOUS
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 1052126bdca2..9c696cb24756 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -76,6 +76,13 @@ config HAVE_OBJTOOL_MCOUNT
 	help
 	  Arch supports objtool --mcount
 
+config HAVE_OBJTOOL_NOP_MCOUNT
+	bool
+	help
+	  Arch supports the objtool options --mcount with --mnop.
+	  An architecture can select this if it wants to enable nop'ing
+	  of ftrace locations.
+
 config HAVE_C_RECORDMCOUNT
 	bool
 	help
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 3fb6a99e78c4..ce14e3b8577f 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -234,6 +234,7 @@ objtool_args =								\
 	$(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)		\
 	$(if $(CONFIG_X86_KERNEL_IBT), --ibt)				\
 	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
+	$(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mnop)                 \
 	$(if $(CONFIG_UNWINDER_ORC), --orc)				\
 	$(if $(CONFIG_RETPOLINE), --retpoline)				\
 	$(if $(CONFIG_RETHUNK), --rethunk)				\
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index 24fbe803a0d3..9bd347d3c244 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -82,6 +82,7 @@ const struct option check_options[] = {
 	OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"),
 	OPT_BOOLEAN(0, "link", &opts.link, "object is a linked object"),
 	OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"),
+	OPT_BOOLEAN(0, "mnop", &opts.mnop, "nop out mcount call sites"),
 	OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"),
 	OPT_BOOLEAN(0, "sec-address", &opts.sec_address, "print section addresses in warnings"),
 	OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"),
@@ -150,6 +151,16 @@ static bool opts_valid(void)
 	return false;
 }
 
+static bool mnop_opts_valid(void)
+{
+	if (opts.mnop && !opts.mcount) {
+		ERROR("--mnop requires --mcount");
+		return false;
+	}
+
+	return true;
+}
+
 static bool link_opts_valid(struct objtool_file *file)
 {
 	if (opts.link)
@@ -198,6 +209,9 @@ int objtool_run(int argc, const char **argv)
 	if (!file)
 		return 1;
 
+	if (!mnop_opts_valid())
+		return 1;
+
 	if (!link_opts_valid(file))
 		return 1;
 
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 738de23cb9e8..35827e6c6df9 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1233,17 +1233,18 @@ static void annotate_call_site(struct objtool_file *file,
 	if (opts.mcount && sym->fentry) {
 		if (sibling)
 			WARN_FUNC("Tail call to __fentry__ !?!?", insn->sec, insn->offset);
+		if (opts.mnop) {
+			if (reloc) {
+				reloc->type = R_NONE;
+				elf_write_reloc(file->elf, reloc);
+			}
 
-		if (reloc) {
-			reloc->type = R_NONE;
-			elf_write_reloc(file->elf, reloc);
-		}
-
-		elf_write_insn(file->elf, insn->sec,
-			       insn->offset, insn->len,
-			       arch_nop_insn(insn->len));
+			elf_write_insn(file->elf, insn->sec,
+				       insn->offset, insn->len,
+				       arch_nop_insn(insn->len));
 
-		insn->type = INSN_NOP;
+			insn->type = INSN_NOP;
+		}
 
 		list_add_tail(&insn->call_node, &file->mcount_loc_list);
 		return;
diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h
index 42a52f1a0add..0785707c5a92 100644
--- a/tools/objtool/include/objtool/builtin.h
+++ b/tools/objtool/include/objtool/builtin.h
@@ -31,6 +31,7 @@ struct opts {
 	bool backup;
 	bool dryrun;
 	bool link;
+	bool mnop;
 	bool module;
 	bool no_unreachable;
 	bool sec_address;
-- 
2.31.1

[PATCH v4 12/16] objtool: Read special sections with alts only when specific options are selected

[Sathvika Vasireddy]

Call add_special_section_alts() only when stackval or orc or uaccess or
noinstr options are passed to objtool.

Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 tools/objtool/check.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 35827e6c6df9..c6457dac6d58 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2372,9 +2372,11 @@ static int decode_sections(struct objtool_file *file)
 	 * Must be before add_jump_destinations(), which depends on 'func'
 	 * being set for alternatives, to enable proper sibling call detection.
 	 */
-	ret = add_special_section_alts(file);
-	if (ret)
-		return ret;
+	if (opts.stackval || opts.orc || opts.uaccess || opts.noinstr) {
+		ret = add_special_section_alts(file);
+		if (ret)
+			return ret;
+	}
 
 	ret = add_jump_destinations(file);
 	if (ret)
-- 
2.31.1

[PATCH v4 13/16] objtool: Use macros to define arch specific reloc types

[Sathvika Vasireddy]

Make relocation types architecture specific.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 tools/objtool/arch/x86/include/arch/elf.h | 2 ++
 tools/objtool/check.c                     | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/objtool/arch/x86/include/arch/elf.h b/tools/objtool/arch/x86/include/arch/elf.h
index 69cc4264b28a..ac14987cf687 100644
--- a/tools/objtool/arch/x86/include/arch/elf.h
+++ b/tools/objtool/arch/x86/include/arch/elf.h
@@ -2,5 +2,7 @@
 #define _OBJTOOL_ARCH_ELF
 
 #define R_NONE R_X86_64_NONE
+#define R_ABS64 R_X86_64_64
+#define R_ABS32 R_X86_64_32
 
 #endif /* _OBJTOOL_ARCH_ELF */
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index c6457dac6d58..35bcd4f90acd 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -885,7 +885,7 @@ static int create_mcount_loc_sections(struct objtool_file *file)
 		memset(loc, 0, addrsize);
 
 		if (elf_add_reloc_to_insn(file->elf, sec, idx,
-					  R_X86_64_64,
+					  addrsize == sizeof(u64) ? R_ABS64 : R_ABS32,
 					  insn->sec, insn->offset))
 			return -1;
 
-- 
2.31.1

[PATCH v4 14/16] objtool: Add arch specific function arch_ftrace_match()

[Sathvika Vasireddy]

Add architecture specific function to look for relocation records
pointing to architecture specific symbols.

Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 tools/objtool/arch/x86/decode.c      | 5 +++++
 tools/objtool/check.c                | 2 +-
 tools/objtool/include/objtool/arch.h | 2 ++
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index c260006106be..28263e231c58 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -23,6 +23,11 @@
 #include <objtool/builtin.h>
 #include <arch/elf.h>
 
+int arch_ftrace_match(char *name)
+{
+	return !strcmp(name, "__fentry__");
+}
+
 static int is_x86_64(const struct elf *elf)
 {
 	switch (elf->ehdr.e_machine) {
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 35bcd4f90acd..856ea80b1cfc 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2296,7 +2296,7 @@ static int classify_symbols(struct objtool_file *file)
 			if (arch_is_rethunk(func))
 				func->return_thunk = true;
 
-			if (!strcmp(func->name, "__fentry__"))
+			if (arch_ftrace_match(func->name))
 				func->fentry = true;
 
 			if (is_profiling_func(func->name))
diff --git a/tools/objtool/include/objtool/arch.h b/tools/objtool/include/objtool/arch.h
index beb2f3aa94ff..5149330f400f 100644
--- a/tools/objtool/include/objtool/arch.h
+++ b/tools/objtool/include/objtool/arch.h
@@ -69,6 +69,8 @@ struct stack_op {
 
 struct instruction;
 
+int arch_ftrace_match(char *name);
+
 void arch_initial_func_cfi_state(struct cfi_init_state *state);
 
 int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
-- 
2.31.1

[PATCH v4 15/16] objtool/powerpc: Enable objtool to be built on ppc

[Sathvika Vasireddy]

This patch adds [stub] implementations for required functions, inorder
to enable objtool build on powerpc.

Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
[Christophe Leroy: powerpc: Add missing asm/asm.h for objtool,
Use local variables for type and imm in arch_decode_instruction(),
Adapt len for prefixed instructions.]
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/Kconfig                          |  1 +
 arch/powerpc/include/asm/asm.h                |  7 ++
 tools/objtool/arch/powerpc/Build              |  2 +
 tools/objtool/arch/powerpc/decode.c           | 85 +++++++++++++++++++
 .../arch/powerpc/include/arch/cfi_regs.h      | 11 +++
 tools/objtool/arch/powerpc/include/arch/elf.h |  8 ++
 .../arch/powerpc/include/arch/special.h       | 21 +++++
 tools/objtool/arch/powerpc/special.c          | 19 +++++
 8 files changed, 154 insertions(+)
 create mode 100644 arch/powerpc/include/asm/asm.h
 create mode 100644 tools/objtool/arch/powerpc/Build
 create mode 100644 tools/objtool/arch/powerpc/decode.c
 create mode 100644 tools/objtool/arch/powerpc/include/arch/cfi_regs.h
 create mode 100644 tools/objtool/arch/powerpc/include/arch/elf.h
 create mode 100644 tools/objtool/arch/powerpc/include/arch/special.h
 create mode 100644 tools/objtool/arch/powerpc/special.c

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 4c466acdc70d..dc05cd23c233 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -237,6 +237,7 @@ config PPC
 	select HAVE_MOD_ARCH_SPECIFIC
 	select HAVE_NMI				if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
 	select HAVE_OPTPROBES
+	select HAVE_OBJTOOL			if PPC32 || MPROFILE_KERNEL
 	select HAVE_PERF_EVENTS
 	select HAVE_PERF_EVENTS_NMI		if PPC64
 	select HAVE_PERF_REGS
diff --git a/arch/powerpc/include/asm/asm.h b/arch/powerpc/include/asm/asm.h
new file mode 100644
index 000000000000..86f46b604e9a
--- /dev/null
+++ b/arch/powerpc/include/asm/asm.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_ASM_H
+#define _ASM_POWERPC_ASM_H
+
+#define _ASM_PTR	" .long "
+
+#endif /* _ASM_POWERPC_ASM_H */
diff --git a/tools/objtool/arch/powerpc/Build b/tools/objtool/arch/powerpc/Build
new file mode 100644
index 000000000000..d24d5636a5b8
--- /dev/null
+++ b/tools/objtool/arch/powerpc/Build
@@ -0,0 +1,2 @@
+objtool-y += decode.o
+objtool-y += special.o
diff --git a/tools/objtool/arch/powerpc/decode.c b/tools/objtool/arch/powerpc/decode.c
new file mode 100644
index 000000000000..dcd0975cad6b
--- /dev/null
+++ b/tools/objtool/arch/powerpc/decode.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <objtool/check.h>
+#include <objtool/elf.h>
+#include <objtool/arch.h>
+#include <objtool/warn.h>
+#include <objtool/builtin.h>
+#include <objtool/endianness.h>
+
+unsigned long arch_dest_reloc_offset(int addend)
+{
+	return addend;
+}
+
+bool arch_callee_saved_reg(unsigned char reg)
+{
+	return false;
+}
+
+int arch_decode_hint_reg(u8 sp_reg, int *base)
+{
+	exit(-1);
+}
+
+const char *arch_nop_insn(int len)
+{
+	exit(-1);
+}
+
+const char *arch_ret_insn(int len)
+{
+	exit(-1);
+}
+
+int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
+			    unsigned long offset, unsigned int maxlen,
+			    unsigned int *len, enum insn_type *type,
+			    unsigned long *immediate,
+			    struct list_head *ops_list)
+{
+	unsigned int opcode;
+	enum insn_type typ;
+	unsigned long imm;
+	u32 insn;
+
+	insn = bswap_if_needed(file->elf, *(u32 *)(sec->data->d_buf + offset));
+	opcode = insn >> 26;
+	typ = INSN_OTHER;
+	imm = 0;
+
+	if (opcode == 1)
+		*len = 8;
+	else
+		*len = 4;
+
+	*type = typ;
+	*immediate = imm;
+
+	return 0;
+}
+
+unsigned long arch_jump_destination(struct instruction *insn)
+{
+	return insn->offset + insn->immediate;
+}
+
+void arch_initial_func_cfi_state(struct cfi_init_state *state)
+{
+	int i;
+
+	for (i = 0; i < CFI_NUM_REGS; i++) {
+		state->regs[i].base = CFI_UNDEFINED;
+		state->regs[i].offset = 0;
+	}
+
+	/* initial CFA (call frame address) */
+	state->cfa.base = CFI_SP;
+	state->cfa.offset = 0;
+
+	/* initial LR (return address) */
+	state->regs[CFI_RA].base = CFI_CFA;
+	state->regs[CFI_RA].offset = 0;
+}
diff --git a/tools/objtool/arch/powerpc/include/arch/cfi_regs.h b/tools/objtool/arch/powerpc/include/arch/cfi_regs.h
new file mode 100644
index 000000000000..59638ebeafc8
--- /dev/null
+++ b/tools/objtool/arch/powerpc/include/arch/cfi_regs.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef _OBJTOOL_CFI_REGS_H
+#define _OBJTOOL_CFI_REGS_H
+
+#define CFI_BP 1
+#define CFI_SP CFI_BP
+#define CFI_RA 32
+#define CFI_NUM_REGS 33
+
+#endif
diff --git a/tools/objtool/arch/powerpc/include/arch/elf.h b/tools/objtool/arch/powerpc/include/arch/elf.h
new file mode 100644
index 000000000000..3c8ebb7d2a6b
--- /dev/null
+++ b/tools/objtool/arch/powerpc/include/arch/elf.h
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef _OBJTOOL_ARCH_ELF
+#define _OBJTOOL_ARCH_ELF
+
+#define R_NONE R_PPC_NONE
+
+#endif /* _OBJTOOL_ARCH_ELF */
diff --git a/tools/objtool/arch/powerpc/include/arch/special.h b/tools/objtool/arch/powerpc/include/arch/special.h
new file mode 100644
index 000000000000..ffef9ada7133
--- /dev/null
+++ b/tools/objtool/arch/powerpc/include/arch/special.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _PPC_ARCH_SPECIAL_H
+#define _PPC_ARCH_SPECIAL_H
+
+#define EX_ENTRY_SIZE 8
+#define EX_ORIG_OFFSET 0
+#define EX_NEW_OFFSET 4
+
+#define JUMP_ENTRY_SIZE 16
+#define JUMP_ORIG_OFFSET 0
+#define JUMP_NEW_OFFSET 4
+#define JUMP_KEY_OFFSET 8
+
+#define ALT_ENTRY_SIZE 12
+#define ALT_ORIG_OFFSET 0
+#define ALT_NEW_OFFSET 4
+#define ALT_FEATURE_OFFSET 8
+#define ALT_ORIG_LEN_OFFSET 10
+#define ALT_NEW_LEN_OFFSET 11
+
+#endif /* _PPC_ARCH_SPECIAL_H */
diff --git a/tools/objtool/arch/powerpc/special.c b/tools/objtool/arch/powerpc/special.c
new file mode 100644
index 000000000000..d33868147196
--- /dev/null
+++ b/tools/objtool/arch/powerpc/special.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <string.h>
+#include <stdlib.h>
+#include <objtool/special.h>
+#include <objtool/builtin.h>
+
+
+bool arch_support_alt_relocation(struct special_alt *special_alt,
+				 struct instruction *insn,
+				 struct reloc *reloc)
+{
+	exit(-1);
+}
+
+struct reloc *arch_find_switch_table(struct objtool_file *file,
+				    struct instruction *insn)
+{
+	exit(-1);
+}
-- 
2.31.1

[PATCH v4 16/16] objtool/powerpc: Add --mcount specific implementation

[Sathvika Vasireddy]

This patch enables objtool --mcount on powerpc, and adds implementation
specific to powerpc.

Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 arch/powerpc/Kconfig                          |  1 +
 tools/objtool/arch/powerpc/decode.c           | 16 ++++++++++++++++
 tools/objtool/arch/powerpc/include/arch/elf.h |  2 ++
 3 files changed, 19 insertions(+)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index dc05cd23c233..6be2e68fa9eb 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -238,6 +238,7 @@ config PPC
 	select HAVE_NMI				if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
 	select HAVE_OPTPROBES
 	select HAVE_OBJTOOL			if PPC32 || MPROFILE_KERNEL
+	select HAVE_OBJTOOL_MCOUNT		if HAVE_OBJTOOL
 	select HAVE_PERF_EVENTS
 	select HAVE_PERF_EVENTS_NMI		if PPC64
 	select HAVE_PERF_REGS
diff --git a/tools/objtool/arch/powerpc/decode.c b/tools/objtool/arch/powerpc/decode.c
index dcd0975cad6b..01cade98b49e 100644
--- a/tools/objtool/arch/powerpc/decode.c
+++ b/tools/objtool/arch/powerpc/decode.c
@@ -9,6 +9,11 @@
 #include <objtool/builtin.h>
 #include <objtool/endianness.h>
 
+int arch_ftrace_match(char *name)
+{
+	return !strcmp(name, "_mcount");
+}
+
 unsigned long arch_dest_reloc_offset(int addend)
 {
 	return addend;
@@ -50,6 +55,17 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec
 	typ = INSN_OTHER;
 	imm = 0;
 
+	switch (opcode) {
+	case 18: /* b[l][a] */
+		if ((insn & 3) == 1) /* bl */
+			typ = INSN_CALL;
+
+		imm = insn & 0x3fffffc;
+		if (imm & 0x2000000)
+			imm -= 0x4000000;
+		break;
+	}
+
 	if (opcode == 1)
 		*len = 8;
 	else
diff --git a/tools/objtool/arch/powerpc/include/arch/elf.h b/tools/objtool/arch/powerpc/include/arch/elf.h
index 3c8ebb7d2a6b..73f9ae172fe5 100644
--- a/tools/objtool/arch/powerpc/include/arch/elf.h
+++ b/tools/objtool/arch/powerpc/include/arch/elf.h
@@ -4,5 +4,7 @@
 #define _OBJTOOL_ARCH_ELF
 
 #define R_NONE R_PPC_NONE
+#define R_ABS64 R_PPC64_ADDR64
+#define R_ABS32 R_PPC_ADDR32
 
 #endif /* _OBJTOOL_ARCH_ELF */
-- 
2.31.1

Re: [PATCH v4 11/16] objtool: Add --mnop as an option to --mcount

[Christophe Leroy]

Le 02/10/2022 à 12:42, Sathvika Vasireddy a écrit :
> Some architectures (powerpc) may not support ftrace locations being nop'ed
> out at build time. Introduce CONFIG_HAVE_OBJTOOL_NOP_MCOUNT for objtool, as
> a means for architectures to enable nop'ing of ftrace locations. Add --mnop
> as an option to objtool --mcount, to indicate support for the same.
> 
> Also, make sure that --mnop can be passed as an option to objtool only when
> --mcount is passed.
> 
> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>

> ---
>   Makefile                                |  4 +++-
>   arch/x86/Kconfig                        |  1 +
>   kernel/trace/Kconfig                    |  7 +++++++
>   scripts/Makefile.lib                    |  1 +
>   tools/objtool/builtin-check.c           | 14 ++++++++++++++
>   tools/objtool/check.c                   | 19 ++++++++++---------
>   tools/objtool/include/objtool/builtin.h |  1 +
>   7 files changed, 37 insertions(+), 10 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index a5e9d9388649..b2230ad14748 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -857,7 +857,9 @@ ifdef CONFIG_FTRACE_MCOUNT_USE_CC
>     endif
>   endif
>   ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
> -  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
> +  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
> +    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
> +  endif
>   endif
>   ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
>     ifdef CONFIG_HAVE_C_RECORDMCOUNT
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index f9920f1341c8..2a79a05c4402 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -189,6 +189,7 @@ config X86
>   	select HAVE_CONTEXT_TRACKING_USER_OFFSTACK	if HAVE_CONTEXT_TRACKING_USER
>   	select HAVE_C_RECORDMCOUNT
>   	select HAVE_OBJTOOL_MCOUNT		if HAVE_OBJTOOL
> +	select HAVE_OBJTOOL_NOP_MCOUNT		if HAVE_OBJTOOL_MCOUNT
>   	select HAVE_BUILDTIME_MCOUNT_SORT
>   	select HAVE_DEBUG_KMEMLEAK
>   	select HAVE_DMA_CONTIGUOUS
> diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
> index 1052126bdca2..9c696cb24756 100644
> --- a/kernel/trace/Kconfig
> +++ b/kernel/trace/Kconfig
> @@ -76,6 +76,13 @@ config HAVE_OBJTOOL_MCOUNT
>   	help
>   	  Arch supports objtool --mcount
>   
> +config HAVE_OBJTOOL_NOP_MCOUNT
> +	bool
> +	help
> +	  Arch supports the objtool options --mcount with --mnop.
> +	  An architecture can select this if it wants to enable nop'ing
> +	  of ftrace locations.
> +
>   config HAVE_C_RECORDMCOUNT
>   	bool
>   	help
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 3fb6a99e78c4..ce14e3b8577f 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -234,6 +234,7 @@ objtool_args =								\
>   	$(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)		\
>   	$(if $(CONFIG_X86_KERNEL_IBT), --ibt)				\
>   	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
> +	$(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mnop)                 \
>   	$(if $(CONFIG_UNWINDER_ORC), --orc)				\
>   	$(if $(CONFIG_RETPOLINE), --retpoline)				\
>   	$(if $(CONFIG_RETHUNK), --rethunk)				\
> diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
> index 24fbe803a0d3..9bd347d3c244 100644
> --- a/tools/objtool/builtin-check.c
> +++ b/tools/objtool/builtin-check.c
> @@ -82,6 +82,7 @@ const struct option check_options[] = {
>   	OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"),
>   	OPT_BOOLEAN(0, "link", &opts.link, "object is a linked object"),
>   	OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"),
> +	OPT_BOOLEAN(0, "mnop", &opts.mnop, "nop out mcount call sites"),
>   	OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"),
>   	OPT_BOOLEAN(0, "sec-address", &opts.sec_address, "print section addresses in warnings"),
>   	OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"),
> @@ -150,6 +151,16 @@ static bool opts_valid(void)
>   	return false;
>   }
>   
> +static bool mnop_opts_valid(void)
> +{
> +	if (opts.mnop && !opts.mcount) {
> +		ERROR("--mnop requires --mcount");
> +		return false;
> +	}
> +
> +	return true;
> +}
> +
>   static bool link_opts_valid(struct objtool_file *file)
>   {
>   	if (opts.link)
> @@ -198,6 +209,9 @@ int objtool_run(int argc, const char **argv)
>   	if (!file)
>   		return 1;
>   
> +	if (!mnop_opts_valid())
> +		return 1;
> +
>   	if (!link_opts_valid(file))
>   		return 1;
>   
> diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> index 738de23cb9e8..35827e6c6df9 100644
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -1233,17 +1233,18 @@ static void annotate_call_site(struct objtool_file *file,
>   	if (opts.mcount && sym->fentry) {
>   		if (sibling)
>   			WARN_FUNC("Tail call to __fentry__ !?!?", insn->sec, insn->offset);
> +		if (opts.mnop) {
> +			if (reloc) {
> +				reloc->type = R_NONE;
> +				elf_write_reloc(file->elf, reloc);
> +			}
>   
> -		if (reloc) {
> -			reloc->type = R_NONE;
> -			elf_write_reloc(file->elf, reloc);
> -		}
> -
> -		elf_write_insn(file->elf, insn->sec,
> -			       insn->offset, insn->len,
> -			       arch_nop_insn(insn->len));
> +			elf_write_insn(file->elf, insn->sec,
> +				       insn->offset, insn->len,
> +				       arch_nop_insn(insn->len));
>   
> -		insn->type = INSN_NOP;
> +			insn->type = INSN_NOP;
> +		}
>   
>   		list_add_tail(&insn->call_node, &file->mcount_loc_list);
>   		return;
> diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h
> index 42a52f1a0add..0785707c5a92 100644
> --- a/tools/objtool/include/objtool/builtin.h
> +++ b/tools/objtool/include/objtool/builtin.h
> @@ -31,6 +31,7 @@ struct opts {
>   	bool backup;
>   	bool dryrun;
>   	bool link;
> +	bool mnop;
>   	bool module;
>   	bool no_unreachable;
>   	bool sec_address;

Re: [PATCH v4 02/16] powerpc: Override __ALIGN and __ALIGN_STR macros

[Christophe Leroy]

Le 02/10/2022 à 12:42, Sathvika Vasireddy a écrit :
> In a subsequent patch, we would want to annotate powerpc assembly functions
> with SYM_FUNC_START_LOCAL macro. This macro depends on __ALIGN macro.
> 
> The default expansion of __ALIGN macro is:
>          #define __ALIGN      .align 4,0x90
> 
> So, override __ALIGN and __ALIGN_STR macros to use the same alignment as
> that of the existing _GLOBAL macro. Also, do not pad with 0x90, because
> repeated 0x90s are not a nop or trap on powerpc.
> 
> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>

> ---
>   arch/powerpc/include/asm/linkage.h | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/arch/powerpc/include/asm/linkage.h b/arch/powerpc/include/asm/linkage.h
> index b71b9582e754..b88d1d2cf304 100644
> --- a/arch/powerpc/include/asm/linkage.h
> +++ b/arch/powerpc/include/asm/linkage.h
> @@ -4,6 +4,9 @@
>   
>   #include <asm/types.h>
>   
> +#define __ALIGN		.align 2
> +#define __ALIGN_STR	".align 2"
> +
>   #ifdef CONFIG_PPC64_ELF_ABI_V1
>   #define cond_syscall(x) \
>   	asm ("\t.weak " #x "\n\t.set " #x ", sys_ni_syscall\n"		\

Re: [PATCH v4 12/16] objtool: Read special sections with alts only when specific options are selected

[Christophe Leroy]

Le 02/10/2022 à 12:42, Sathvika Vasireddy a écrit :
> Call add_special_section_alts() only when stackval or orc or uaccess or
> noinstr options are passed to objtool.
> 
> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>

> ---
>   tools/objtool/check.c | 8 +++++---
>   1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> index 35827e6c6df9..c6457dac6d58 100644
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -2372,9 +2372,11 @@ static int decode_sections(struct objtool_file *file)
>   	 * Must be before add_jump_destinations(), which depends on 'func'
>   	 * being set for alternatives, to enable proper sibling call detection.
>   	 */
> -	ret = add_special_section_alts(file);
> -	if (ret)
> -		return ret;
> +	if (opts.stackval || opts.orc || opts.uaccess || opts.noinstr) {
> +		ret = add_special_section_alts(file);
> +		if (ret)
> +			return ret;
> +	}
>   
>   	ret = add_jump_destinations(file);
>   	if (ret)

Re: [PATCH v4 16/16] objtool/powerpc: Add --mcount specific implementation

[Christophe Leroy]

Le 02/10/2022 à 12:42, Sathvika Vasireddy a écrit :
> This patch enables objtool --mcount on powerpc, and adds implementation
> specific to powerpc.
> 
> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>

> ---
>   arch/powerpc/Kconfig                          |  1 +
>   tools/objtool/arch/powerpc/decode.c           | 16 ++++++++++++++++
>   tools/objtool/arch/powerpc/include/arch/elf.h |  2 ++
>   3 files changed, 19 insertions(+)
> 
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index dc05cd23c233..6be2e68fa9eb 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -238,6 +238,7 @@ config PPC
>   	select HAVE_NMI				if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
>   	select HAVE_OPTPROBES
>   	select HAVE_OBJTOOL			if PPC32 || MPROFILE_KERNEL
> +	select HAVE_OBJTOOL_MCOUNT		if HAVE_OBJTOOL
>   	select HAVE_PERF_EVENTS
>   	select HAVE_PERF_EVENTS_NMI		if PPC64
>   	select HAVE_PERF_REGS
> diff --git a/tools/objtool/arch/powerpc/decode.c b/tools/objtool/arch/powerpc/decode.c
> index dcd0975cad6b..01cade98b49e 100644
> --- a/tools/objtool/arch/powerpc/decode.c
> +++ b/tools/objtool/arch/powerpc/decode.c
> @@ -9,6 +9,11 @@
>   #include <objtool/builtin.h>
>   #include <objtool/endianness.h>
>   
> +int arch_ftrace_match(char *name)
> +{
> +	return !strcmp(name, "_mcount");
> +}
> +
>   unsigned long arch_dest_reloc_offset(int addend)
>   {
>   	return addend;
> @@ -50,6 +55,17 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec
>   	typ = INSN_OTHER;
>   	imm = 0;
>   
> +	switch (opcode) {
> +	case 18: /* b[l][a] */
> +		if ((insn & 3) == 1) /* bl */
> +			typ = INSN_CALL;
> +
> +		imm = insn & 0x3fffffc;
> +		if (imm & 0x2000000)
> +			imm -= 0x4000000;
> +		break;
> +	}
> +
>   	if (opcode == 1)
>   		*len = 8;
>   	else
> diff --git a/tools/objtool/arch/powerpc/include/arch/elf.h b/tools/objtool/arch/powerpc/include/arch/elf.h
> index 3c8ebb7d2a6b..73f9ae172fe5 100644
> --- a/tools/objtool/arch/powerpc/include/arch/elf.h
> +++ b/tools/objtool/arch/powerpc/include/arch/elf.h
> @@ -4,5 +4,7 @@
>   #define _OBJTOOL_ARCH_ELF
>   
>   #define R_NONE R_PPC_NONE
> +#define R_ABS64 R_PPC64_ADDR64
> +#define R_ABS32 R_PPC_ADDR32
>   
>   #endif /* _OBJTOOL_ARCH_ELF */

Re: [PATCH v4 03/16] powerpc: Fix objtool unannotated intra-function call warnings

[Naveen N. Rao]

Sathvika Vasireddy wrote:
> 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.
> 
> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
> ---
>  arch/powerpc/kernel/exceptions-64s.S    |  7 +++++--
>  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, 34 insertions(+), 14 deletions(-)

Applying this to powerpc/merge today shows two small conflicts:

> 
> diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
> index 3d0dc133a9ae..56a31424c8b0 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>
> @@ -3075,7 +3076,7 @@ CLOSE_FIXED_SECTION(virt_trampolines);
>  USE_TEXT_SECTION()
> 
>  /* MSR[RI] should be clear because this uses SRR[01] */
> -enable_machine_check:
> +SYM_FUNC_START_LOCAL(enable_machine_check)

This is now a _GLOBAL(), so this hunk and the below 
SYM_FUNC_END(enable_machine_check) change can be dropped.

>  	mflr	r0
>  	bcl	20,31,$+4
>  0:	mflr	r3
> @@ -3087,9 +3088,10 @@ enable_machine_check:
>  	RFI_TO_KERNEL
>  1:	mtlr	r0
>  	blr
> +SYM_FUNC_END(enable_machine_check)
> 
>  /* MSR[RI] should be clear because this uses SRR[01] */
> -disable_machine_check:
> +SYM_FUNC_START_LOCAL(disable_machine_check)
>  	mflr	r0
>  	bcl	20,31,$+4
>  0:	mflr	r3
> @@ -3102,3 +3104,4 @@ 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 cf2c08902c05..10e2d43420d0 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>
> @@ -465,7 +466,7 @@ 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
> @@ -476,6 +477,7 @@ __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
>  	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 fd6d8d3a548e..b36fb89ff718 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

The #ifdef is now for CONFIG_PPC_BOOK3E_64.

The rest of the series apply properly.


- Naveen

Re: [PATCH v4 11/16] objtool: Add --mnop as an option to --mcount

[Naveen N. Rao]

Sathvika Vasireddy wrote:
> Some architectures (powerpc) may not support ftrace locations being nop'ed
> out at build time. Introduce CONFIG_HAVE_OBJTOOL_NOP_MCOUNT for objtool, as
> a means for architectures to enable nop'ing of ftrace locations. Add --mnop
> as an option to objtool --mcount, to indicate support for the same.
> 
> Also, make sure that --mnop can be passed as an option to objtool only when
> --mcount is passed.
> 
> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
> ---
>  Makefile                                |  4 +++-
>  arch/x86/Kconfig                        |  1 +
>  kernel/trace/Kconfig                    |  7 +++++++
>  scripts/Makefile.lib                    |  1 +
>  tools/objtool/builtin-check.c           | 14 ++++++++++++++
>  tools/objtool/check.c                   | 19 ++++++++++---------
>  tools/objtool/include/objtool/builtin.h |  1 +
>  7 files changed, 37 insertions(+), 10 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index a5e9d9388649..b2230ad14748 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -857,7 +857,9 @@ ifdef CONFIG_FTRACE_MCOUNT_USE_CC
>    endif
>  endif
>  ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
> -  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
> +  ifdef CONFIG_HAVE_OBJTOOL_NOP_MCOUNT
> +    CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
> +  endif
>  endif
>  ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
>    ifdef CONFIG_HAVE_C_RECORDMCOUNT
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index f9920f1341c8..2a79a05c4402 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -189,6 +189,7 @@ config X86
>  	select HAVE_CONTEXT_TRACKING_USER_OFFSTACK	if HAVE_CONTEXT_TRACKING_USER
>  	select HAVE_C_RECORDMCOUNT
>  	select HAVE_OBJTOOL_MCOUNT		if HAVE_OBJTOOL
> +	select HAVE_OBJTOOL_NOP_MCOUNT		if HAVE_OBJTOOL_MCOUNT
>  	select HAVE_BUILDTIME_MCOUNT_SORT
>  	select HAVE_DEBUG_KMEMLEAK
>  	select HAVE_DMA_CONTIGUOUS
> diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
> index 1052126bdca2..9c696cb24756 100644
> --- a/kernel/trace/Kconfig
> +++ b/kernel/trace/Kconfig
> @@ -76,6 +76,13 @@ config HAVE_OBJTOOL_MCOUNT
>  	help
>  	  Arch supports objtool --mcount
> 
> +config HAVE_OBJTOOL_NOP_MCOUNT
> +	bool
> +	help
> +	  Arch supports the objtool options --mcount with --mnop.
> +	  An architecture can select this if it wants to enable nop'ing
> +	  of ftrace locations.
> +
>  config HAVE_C_RECORDMCOUNT
>  	bool
>  	help
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 3fb6a99e78c4..ce14e3b8577f 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -234,6 +234,7 @@ objtool_args =								\
>  	$(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)		\
>  	$(if $(CONFIG_X86_KERNEL_IBT), --ibt)				\
>  	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
> +	$(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mnop)                 \

This still won't help: for instance, if CONFIG_FTRACE itself is 
disabled. I think we should make this depend on 
CONFIG_FTRACE_MCOUNT_USE_OBJTOOL. The below change works for me:

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 54d2d6451bdacc..fd3f55a1fdb7bb 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -245,8 +245,8 @@ objtool_args =                                                              \
        $(if $(CONFIG_HAVE_JUMP_LABEL_HACK), --hacks=jump_label)        \
        $(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)              \
        $(if $(CONFIG_X86_KERNEL_IBT), --ibt)                           \
-       $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)             \
-       $(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mnop)                 \
+        $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL),                       \
+             $(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mcount --mnop, --mcount)) \
        $(if $(CONFIG_UNWINDER_ORC), --orc)                             \
        $(if $(CONFIG_RETPOLINE), --retpoline)                          \
        $(if $(CONFIG_RETHUNK), --rethunk)                              \


- Naveen

Re: [PATCH v4 00/16] objtool: Enable and implement --mcount option on powerpc

[Naveen N. Rao]

Sathvika Vasireddy wrote:
> This patchset enables and implements objtool --mcount
> option on powerpc. This applies atop powerpc/merge branch.
> 
> Changelog:
> 
> ----
> v4:
> 
> * Patch 11/16 - Introduce a new config option
> 		CONFIG_HAVE_OBJTOOL_NOP_MCOUNT as a means for
> 		architectures to enable nop'ing ftrace locations.
> 
> 	      - Remove Acked-by tag from Peter Zijlstra (Intel),
> 		and Reviewed-by tag from Christophe Leroy. 
> 		[This is done because I reworked the patch to add
> 		a new config option to objtool. Please let me know
> 		if you want me to retain the tags. Thanks!]
> 
> * Patch 16/16 - Rework the patch to handle only 'bl' instruction
> 		decoding. 

With changes to the two patches in this series that I have described, 
and with my patch to have ftrace ignore weak symbols (*) applied, I 
built a ppc64le config.

(*) http://lkml.kernel.org/r/20220809105425.424045-1-naveen.n.rao@linux.vnet.ibm.com

I then used the below diff to disable objtool and to build with 
recordmcount:

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 7e28a8fd4c24fa..81c9f895d69012 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -238,8 +238,6 @@ config PPC
        select HAVE_MOD_ARCH_SPECIFIC
        select HAVE_NMI                         if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
        select HAVE_OPTPROBES
-       select HAVE_OBJTOOL                     if PPC32 || MPROFILE_KERNEL
-       select HAVE_OBJTOOL_MCOUNT              if HAVE_OBJTOOL
        select HAVE_PERF_EVENTS
        select HAVE_PERF_EVENTS_NMI             if PPC64
        select HAVE_PERF_REGS

Comparing available_filter_functions across the two builds showed the 
below differences:
  $ diff ftrace_funcs_recordmcount_20221010.sort.out ftrace_funcs_objtool_20221010.sort.out 
  6799d6798
  < __dev_alloc_name
  6800a6800
  > dev_alloc_name_ns
  11680d11679
  < find_zone.isra.0
  22396a22396
  > ns_capable_common.part.0

All the above changes are down to compiler optimizations and shuffling 
due to CONFIG_OBJTOOL being enabled and changing annotate_unreachable().

As such, for this series:
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>


Josh,
Are you ok if this series is taken in through the powerpc tree?


- Naveen

Re: [PATCH v4 11/16] objtool: Add --mnop as an option to --mcount

[Josh Poimboeuf]

On Mon, Oct 10, 2022 at 05:07:46PM +0530, Naveen N. Rao wrote:
> > +++ b/scripts/Makefile.lib
> > @@ -234,6 +234,7 @@ objtool_args =								\
> >  	$(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)		\
> >  	$(if $(CONFIG_X86_KERNEL_IBT), --ibt)				\
> >  	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
> > +	$(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mnop)                 \
> 
> This still won't help: for instance, if CONFIG_FTRACE itself is disabled. I
> think we should make this depend on CONFIG_FTRACE_MCOUNT_USE_OBJTOOL. The
> below change works for me:
> 
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 54d2d6451bdacc..fd3f55a1fdb7bb 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -245,8 +245,8 @@ objtool_args =                                                              \
>        $(if $(CONFIG_HAVE_JUMP_LABEL_HACK), --hacks=jump_label)        \
>        $(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)              \
>        $(if $(CONFIG_X86_KERNEL_IBT), --ibt)                           \
> -       $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)             \
> -       $(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mnop)                 \
> +        $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL),                       \
> +             $(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mcount --mnop, --mcount)) \
>        $(if $(CONFIG_UNWINDER_ORC), --orc)                             \
>        $(if $(CONFIG_RETPOLINE), --retpoline)                          \
>        $(if $(CONFIG_RETHUNK), --rethunk)                              \

This has a new conflict, may need something like:

--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -256,6 +256,9 @@ objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK)		+= --hacks=jump_label
 objtool-args-$(CONFIG_HAVE_NOINSTR_HACK)		+= --hacks=noinstr
 objtool-args-$(CONFIG_X86_KERNEL_IBT)			+= --ibt
 objtool-args-$(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL)	+= --mcount
+ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
+objtool-args-$(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT)		+= --mnop
+endif
 objtool-args-$(CONFIG_UNWINDER_ORC)			+= --orc
 objtool-args-$(CONFIG_RETPOLINE)			+= --retpoline
 objtool-args-$(CONFIG_RETHUNK)				+= --rethunk

Re: [PATCH v4 11/16] objtool: Add --mnop as an option to --mcount

[Naveen N. Rao]

Josh Poimboeuf wrote:
> On Mon, Oct 10, 2022 at 05:07:46PM +0530, Naveen N. Rao wrote:
>> > +++ b/scripts/Makefile.lib
>> > @@ -234,6 +234,7 @@ objtool_args =								\
>> >  	$(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)		\
>> >  	$(if $(CONFIG_X86_KERNEL_IBT), --ibt)				\
>> >  	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
>> > +	$(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mnop)                 \
>> 
>> This still won't help: for instance, if CONFIG_FTRACE itself is disabled. I
>> think we should make this depend on CONFIG_FTRACE_MCOUNT_USE_OBJTOOL. The
>> below change works for me:
>> 
>> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
>> index 54d2d6451bdacc..fd3f55a1fdb7bb 100644
>> --- a/scripts/Makefile.lib
>> +++ b/scripts/Makefile.lib
>> @@ -245,8 +245,8 @@ objtool_args =                                                              \
>>        $(if $(CONFIG_HAVE_JUMP_LABEL_HACK), --hacks=jump_label)        \
>>        $(if $(CONFIG_HAVE_NOINSTR_HACK), --hacks=noinstr)              \
>>        $(if $(CONFIG_X86_KERNEL_IBT), --ibt)                           \
>> -       $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)             \
>> -       $(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mnop)                 \
>> +        $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL),                       \
>> +             $(if $(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT), --mcount --mnop, --mcount)) \
>>        $(if $(CONFIG_UNWINDER_ORC), --orc)                             \
>>        $(if $(CONFIG_RETPOLINE), --retpoline)                          \
>>        $(if $(CONFIG_RETHUNK), --rethunk)                              \
> 
> This has a new conflict, may need something like:
> 
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -256,6 +256,9 @@ objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK)		+= --hacks=jump_label
>  objtool-args-$(CONFIG_HAVE_NOINSTR_HACK)		+= --hacks=noinstr
>  objtool-args-$(CONFIG_X86_KERNEL_IBT)			+= --ibt
>  objtool-args-$(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL)	+= --mcount
> +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
> +objtool-args-$(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT)		+= --mnop
> +endif
>  objtool-args-$(CONFIG_UNWINDER_ORC)			+= --orc
>  objtool-args-$(CONFIG_RETPOLINE)			+= --retpoline
>  objtool-args-$(CONFIG_RETHUNK)				+= --rethunk

Thanks. That's definitely simpler.

I haven't checked if there are any other conflicts with 
tip/objtool/core though. Not sure how to proceed here.


- Naveen

Re: [PATCH v4 00/16] objtool: Enable and implement --mcount option on powerpc

[Josh Poimboeuf]

On Tue, Oct 11, 2022 at 01:20:02PM -0700, Josh Poimboeuf wrote:
> On Mon, Oct 10, 2022 at 05:19:02PM +0530, Naveen N. Rao wrote:
> > All the above changes are down to compiler optimizations and shuffling due
> > to CONFIG_OBJTOOL being enabled and changing annotate_unreachable().
> > 
> > As such, for this series:
> > Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> > Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> > 
> > 
> > Josh,
> > Are you ok if this series is taken in through the powerpc tree?
> 
> Yes, it looks ok to me.  Let me run it through a round of testing.

The testing looked good, so:

  Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>

-- 
Josh

Re: [PATCH v4 00/16] objtool: Enable and implement --mcount option on powerpc

[Naveen N. Rao]

Josh Poimboeuf wrote:
> On Tue, Oct 11, 2022 at 01:20:02PM -0700, Josh Poimboeuf wrote:
>> On Mon, Oct 10, 2022 at 05:19:02PM +0530, Naveen N. Rao wrote:
>> > All the above changes are down to compiler optimizations and shuffling due
>> > to CONFIG_OBJTOOL being enabled and changing annotate_unreachable().
>> > 
>> > As such, for this series:
>> > Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
>> > Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
>> > 
>> > 
>> > Josh,
>> > Are you ok if this series is taken in through the powerpc tree?
>> 
>> Yes, it looks ok to me.  Let me run it through a round of testing.
> 
> The testing looked good, so:
> 
>   Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>

Thanks!

FYI: your previous reply (that you would be testing it) didn't hit my 
inbox and it doesn't seem to have hit the list either.


- Naveen