LinuxLists.cc - [PATCH v2 00/16] objtool: Enable and implement --mcount option on powerpc

2022-08-29 06:01:56

Subject: [PATCH v2 00/16] objtool: Enable and implement --mcount option on powerpc

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

Changelog:

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: Replace unreachable() with it's builtin variant in __WARN_FLAGS()
powerpc: override __ALIGN() and __ALIGN_STR() macros
powerpc: Fix objtool unannotated intra-function call warnings
powerpc: curb objtool unannotated intra-function call 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 | 4 +
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 +
scripts/Makefile.lib | 1 +
tools/objtool/arch/powerpc/Build | 2 +
tools/objtool/arch/powerpc/decode.c | 96 +++++++++++++++++++
.../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 | 8 ++
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 | 51 +++++-----
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 +-
45 files changed, 409 insertions(+), 106 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

2022-08-29 06:06:49

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 16/16] objtool/powerpc: Add --mcount specific implementation

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

Signed-off-by: Sathvika Vasireddy <[email protected]>
---
arch/powerpc/Kconfig | 1 +
tools/objtool/arch/powerpc/decode.c | 22 +++++++++++++++++++
tools/objtool/arch/powerpc/include/arch/elf.h | 2 ++
3 files changed, 25 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 8b6a14680da7..b71c265ed503 100644
--- a/tools/objtool/arch/powerpc/decode.c
+++ b/tools/objtool/arch/powerpc/decode.c
@@ -9,6 +9,14 @@
#include <objtool/builtin.h>
#include <objtool/endianness.h>

+bool arch_ftrace_match(char *name)
+{
+ if (!strcmp(name, "_mcount"))
+ return true;
+
+ return false;
+}
+
unsigned long arch_dest_reloc_offset(int addend)
{
return addend;
@@ -41,12 +49,26 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec
struct list_head *ops_list)
{
u32 insn;
+ unsigned int opcode;

*immediate = 0;
insn = bswap_if_needed(file->elf, *(u32 *)(sec->data->d_buf + offset));
*len = 4;
*type = INSN_OTHER;

+ opcode = insn >> 26;
+
+ switch (opcode) {
+ case 18: /* bl */
+ if ((insn & 3) == 1) {
+ *type = INSN_CALL;
+ *immediate = insn & 0x3fffffc;
+ if (*immediate & 0x2000000)
+ *immediate -= 0x4000000;
+ }
+ break;
+ }
+
return 0;
}

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

2022-08-29 06:12:59

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 10/16] objtool: Use target file class size instead of a compiled constant

From: Christophe Leroy <[email protected]>

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.

Signed-off-by: Christophe Leroy <[email protected]>
---
tools/objtool/check.c | 16 +++++++++-------
tools/objtool/elf.c | 8 ++++++--
tools/objtool/include/objtool/elf.h | 8 ++++++++
3 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index a948b2551520..0ecf41ee73f0 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -851,9 +851,9 @@ 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;
struct instruction *insn;
int idx;
+ int addrsize = elf_class_addrsize(file->elf);

sec = find_section_by_name(file->elf, "__mcount_loc");
if (sec) {
@@ -869,23 +869,25 @@ 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

2022-08-29 06:14:55

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

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

Signed-off-by: Sathvika Vasireddy <[email protected]>
[Christophe Leroy: powerpc: Add missing asm/asm.h for objtool]
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/asm.h | 7 ++
tools/objtool/arch/powerpc/Build | 2 +
tools/objtool/arch/powerpc/decode.c | 74 +++++++++++++++++++
.../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, 143 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..8b6a14680da7
--- /dev/null
+++ b/tools/objtool/arch/powerpc/decode.c
@@ -0,0 +1,74 @@
+// 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)
+{
+ u32 insn;
+
+ *immediate = 0;
+ insn = bswap_if_needed(file->elf, *(u32 *)(sec->data->d_buf + offset));
+ *len = 4;
+ *type = INSN_OTHER;
+
+ 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

2022-08-29 06:23:10

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 03/16] powerpc: Fix objtool unannotated intra-function call warnings

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

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

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

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

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

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

Signed-off-by: Sathvika Vasireddy <[email protected]>
---
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..4242c1a20bcd 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -20,6 +20,7 @@
#include <asm/head-64.h>
#include <asm/feature-fixups.h>
#include <asm/kup.h>
+#include <linux/linkage.h>

/*
* Following are fixed section helper macros.
@@ -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 ([email protected])
*/

+#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..fb96aed2b5c3 100644
--- a/arch/powerpc/kernel/vector.S
+++ b/arch/powerpc/kernel/vector.S
@@ -9,6 +9,7 @@
#include <asm/ptrace.h>
#include <asm/export.h>
#include <asm/asm-compat.h>
+#include <linux/linkage.h>

/*
* Load state from memory into VMX registers including VSCR.
@@ -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 <[email protected]>
*/

+#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..de91118df0c5 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -29,6 +29,7 @@
#include <asm/asm-compat.h>
#include <asm/feature-fixups.h>
#include <asm/cpuidle.h>
+#include <linux/linkage.h>

/* Values in HSTATE_NAPPING(r13) */
#define NAPPING_CEDE 1
@@ -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

2022-08-29 06:23:12

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 11/16] objtool: Add --mnop as an option to --mcount

Architectures can select HAVE_NOP_MCOUNT if they choose
to nop out mcount call sites. If that config option is
selected, then --mnop is passed as an option to objtool,
along with --mcount.

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

Signed-off-by: Sathvika Vasireddy <[email protected]>
---
Makefile | 4 +++-
arch/x86/Kconfig | 1 +
scripts/Makefile.lib | 1 +
tools/objtool/builtin-check.c | 14 ++++++++++++++
tools/objtool/check.c | 19 ++++++++++---------
tools/objtool/include/objtool/builtin.h | 1 +
6 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/Makefile b/Makefile
index c7705f749601..99dd33d8bcfa 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_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..a8dd138df637 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_NOP_MCOUNT if HAVE_OBJTOOL_MCOUNT
select HAVE_BUILDTIME_MCOUNT_SORT
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_CONTIGUOUS
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 3fb6a99e78c4..0610078e057a 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_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 0ecf41ee73f0..3cea58f73878 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1231,17 +1231,18 @@ 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

2022-08-29 06:23:53

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 07/16] powerpc: Skip objtool from running on VDSO files

Do not run objtool on VDSO files, by using
OBJECT_FILES_NON_STANDARD

Suggested-by: Christophe Leroy <[email protected]>
Signed-off-by: Sathvika Vasireddy <[email protected]>
---
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 096b0bf1335f..a49a0d6a1c53 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,$^) $(filter %.o,$^) ; $(cmd_vdso_check)
quiet_cmd_vdso64as = VDSO64A $@
cmd_vdso64as = $(VDSOCC) $(a_flags) $(CC64FLAGS) $(AS64FLAGS) -c -o $@ $<
+
+OBJECT_FILES_NON_STANDARD := y
--
2.31.1

2022-08-29 06:24:55

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 01/16] powerpc: Replace unreachable() with it's builtin variant in __WARN_FLAGS()

objtool is throwing *unannotated intra-function call* warnings in
.c files with a few instructions that are marked unreachable. The
problem comes from the annotate_unreachable() macro that is
called by unreachable(). This annotation is adding a call to a
function with size 0, and objtool does not add such symbols
to the rbtree. Due to this reason, find_call_destination() function
is not able to find the destination symbol for that call.

With the annotation (annotate_unreachable()), gcc seems to
generate a 'bl' to unreachable symbol with size 0. But with
the builtin variant of unreachable (__builtin_unreachable()),
gcc does not emit calls to such symbols and the warnings
go away. Given that the codegen remains same, and that
there are no 'bl' instructions to such symbols emitted, fix
these warnings by replacing unreachable() with it's builtin
variant in __WARN_FLAGS().

Also, add barrier_before_unreachable() before __builtin_unreachable()
to work around a gcc bug [1], for the problem reported at [2].

[1]: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751
[2]: https://lkml.org/lkml/2022/8/25/418

Signed-off-by: Sathvika Vasireddy <[email protected]>
---
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

2022-08-29 06:25:10

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 13/16] objtool: Use macros to define arch specific reloc types

Make relocation types architecture specific.

Signed-off-by: Sathvika Vasireddy <[email protected]>
---
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 5298a143ceac..f1d055467926 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -883,7 +883,7 @@ 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

2022-08-29 06:25:40

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 09/16] objtool: Use target file endianness instead of a compiled constant

From: Christophe Leroy <[email protected]>

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.

Signed-off-by: Christophe Leroy <[email protected]>
---
.../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 ed2fdfeb1d9c..a948b2551520 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2075,7 +2075,7 @@ 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

2022-08-29 06:25:50

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 12/16] objtool: Read special sections with alts only when specific options are selected

This patch reads special sections which have alternate
instructions, only when stackval or orc or uaccess or
noinstr options are passed to objtool.

Signed-off-by: Sathvika Vasireddy <[email protected]>
---
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 3cea58f73878..5298a143ceac 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2370,9 +2370,11 @@ 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

2022-08-29 06:27:00

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 14/16] objtool: Add arch specific function arch_ftrace_match()

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

Suggested-by: Christophe Leroy <[email protected]>
Signed-off-by: Sathvika Vasireddy <[email protected]>
---
tools/objtool/arch/x86/decode.c | 8 ++++++++
tools/objtool/check.c | 2 +-
tools/objtool/include/objtool/arch.h | 2 ++
3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index c260006106be..025598b6b703 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -23,6 +23,14 @@
#include <objtool/builtin.h>
#include <arch/elf.h>

+bool arch_ftrace_match(char *name)
+{
+ if (!strcmp(name, "__fentry__"))
+ return true;
+
+ return false;
+}
+
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 f1d055467926..01ff7504f18d 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2294,7 +2294,7 @@ 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..2ba4b9897285 100644
--- a/tools/objtool/include/objtool/arch.h
+++ b/tools/objtool/include/objtool/arch.h
@@ -69,6 +69,8 @@ struct stack_op {

struct instruction;

+bool 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

2022-08-29 06:27:59

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 05/16] powerpc: Skip objtool from running on drivers/crypto/vmx/aesp8-ppc.o

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 this file, for two main 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.

Second reason is that, at least as far as the objtool --mcount
functionality is concerned, we do not have to run objtool on
that file because that file does not have any calls to _mcount.

Signed-off-by: Sathvika Vasireddy <[email protected]>
---
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

2022-08-29 06:55:48

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 04/16] powerpc: Curb objtool unannotated intra-function warnings

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
call, using ANNOTATE_INTRA_FUNCTION_CALL macro,
to indicate that the branch targets are valid.

Signed-off-by: Sathvika Vasireddy <[email protected]>
---
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 de91118df0c5..ea39a0cf591a 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -30,6 +30,7 @@
#include <asm/feature-fixups.h>
#include <asm/cpuidle.h>
#include <linux/linkage.h>
+#include <linux/objtool.h>

/* Values in HSTATE_NAPPING(r13) */
#define NAPPING_CEDE 1
@@ -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

2022-08-29 06:55:53

by Sathvika Vasireddy

[permalink] [raw]

Subject: [PATCH v2 08/16] objtool: Fix SEGFAULT

From: Christophe Leroy <[email protected]>

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

Signed-off-by: Christophe Leroy <[email protected]>
---
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 91678252a9b6..ed2fdfeb1d9c 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -205,7 +205,7 @@ 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

2022-08-30 06:26:43

Subject: [PATCH v2 00/16] objtool: Enable and implement --mcount option on powerpc

Subject: [PATCH v2 16/16] objtool/powerpc: Add --mcount specific implementation

Subject: [PATCH v2 10/16] objtool: Use target file class size instead of a compiled constant

Subject: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: [PATCH v2 03/16] powerpc: Fix objtool unannotated intra-function call warnings

Subject: [PATCH v2 11/16] objtool: Add --mnop as an option to --mcount

Subject: [PATCH v2 07/16] powerpc: Skip objtool from running on VDSO files

Subject: [PATCH v2 01/16] powerpc: Replace unreachable() with it's builtin variant in __WARN_FLAGS()

Subject: [PATCH v2 13/16] objtool: Use macros to define arch specific reloc types

Subject: [PATCH v2 09/16] objtool: Use target file endianness instead of a compiled constant

Subject: [PATCH v2 12/16] objtool: Read special sections with alts only when specific options are selected

Subject: [PATCH v2 14/16] objtool: Add arch specific function arch_ftrace_match()

Subject: [PATCH v2 05/16] powerpc: Skip objtool from running on drivers/crypto/vmx/aesp8-ppc.o

Subject: [PATCH v2 04/16] powerpc: Curb objtool unannotated intra-function warnings

Subject: [PATCH v2 08/16] objtool: Fix SEGFAULT

Subject: Re: [PATCH v2 01/16] powerpc: Replace unreachable() with it's builtin variant in __WARN_FLAGS()

Subject: Re: [PATCH v2 04/16] powerpc: Curb objtool unannotated intra-function warnings

Subject: Re: [PATCH v2 05/16] powerpc: Skip objtool from running on drivers/crypto/vmx/aesp8-ppc.o

Subject: Re: [PATCH v2 03/16] powerpc: Fix objtool unannotated intra-function call warnings

Subject: Re: [PATCH v2 13/16] objtool: Use macros to define arch specific reloc types

Subject: Re: [PATCH v2 12/16] objtool: Read special sections with alts only when specific options are selected

Subject: Re: [PATCH v2 11/16] objtool: Add --mnop as an option to --mcount

Subject: Re: [PATCH v2 14/16] objtool: Add arch specific function arch_ftrace_match()

Subject: Re: [PATCH v2 07/16] powerpc: Skip objtool from running on VDSO files

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 16/16] objtool/powerpc: Add --mcount specific implementation

Subject: Re: [PATCH v2 03/16] powerpc: Fix objtool unannotated intra-function call warnings

Subject: Re: [PATCH v2 16/16] objtool/powerpc: Add --mcount specific implementation

Subject: Re: [PATCH v2 16/16] objtool/powerpc: Add --mcount specific implementation

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 05/16] powerpc: Skip objtool from running on drivers/crypto/vmx/aesp8-ppc.o

Subject: Re: [PATCH v2 10/16] objtool: Use target file class size instead of a compiled constant

Subject: Re: [PATCH v2 07/16] powerpc: Skip objtool from running on VDSO files

Subject: Re: [PATCH v2 08/16] objtool: Fix SEGFAULT

Subject: Re: [PATCH v2 11/16] objtool: Add --mnop as an option to --mcount

Subject: Re: [PATCH v2 09/16] objtool: Use target file endianness instead of a compiled constant

Subject: Re: [PATCH v2 13/16] objtool: Use macros to define arch specific reloc types

Subject: Re: [PATCH v2 07/16] powerpc: Skip objtool from running on VDSO files

Subject: Re: [PATCH v2 08/16] objtool: Fix SEGFAULT

Subject: Re: [PATCH v2 08/16] objtool: Fix SEGFAULT

Subject: Re: [PATCH v2 11/16] objtool: Add --mnop as an option to --mcount

Subject: Re: [PATCH v2 16/16] objtool/powerpc: Add --mcount specific implementation

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 01/16] powerpc: Replace unreachable() with it's builtin variant in __WARN_FLAGS()

Subject: Re: [PATCH v2 05/16] powerpc: Skip objtool from running on drivers/crypto/vmx/aesp8-ppc.o

Subject: Re: [PATCH v2 03/16] powerpc: Fix objtool unannotated intra-function call warnings

Subject: Re: [PATCH v2 16/16] objtool/powerpc: Add --mcount specific implementation

Subject: Re: [PATCH v2 16/16] objtool/powerpc: Add --mcount specific implementation

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc

Subject: Re: [PATCH v2 15/16] objtool/powerpc: Enable objtool to be built on ppc