[PATCH v2 1/2] mips/kgdb: prepare arch_kgdb_ops for constness

[PATCH v2 1/2] mips/kgdb: prepare arch_kgdb_ops for constness

[Christophe Leroy]

MIPS is the only architecture modifying arch_kgdb_ops during init.
This patch makes the init static, so that it can be changed to
const in following patch, as recommended by checkpatch.pl

Suggested-by: Paul Burton <paul.burton@mips.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 v2: Added acks from Daniel and Paul.

 arch/mips/kernel/kgdb.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c
index eb6c0d582626..31eff1bec577 100644
--- a/arch/mips/kernel/kgdb.c
+++ b/arch/mips/kernel/kgdb.c
@@ -394,18 +394,16 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
 	return -1;
 }
 
-struct kgdb_arch arch_kgdb_ops;
+struct kgdb_arch arch_kgdb_ops = {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	.gdb_bpt_instr = { spec_op << 2, 0x00, 0x00, break_op },
+#else
+	.gdb_bpt_instr = { break_op, 0x00, 0x00, spec_op << 2 },
+#endif
+};
 
 int kgdb_arch_init(void)
 {
-	union mips_instruction insn = {
-		.r_format = {
-			.opcode = spec_op,
-			.func	= break_op,
-		}
-	};
-	memcpy(arch_kgdb_ops.gdb_bpt_instr, insn.byte, BREAK_INSTR_SIZE);
-
 	register_die_notifier(&kgdb_notifier);
 
 	return 0;
-- 
2.13.3

[PATCH v2 2/2] kgdb/treewide: constify struct kgdb_arch arch_kgdb_ops

[Christophe Leroy]

checkpatch.pl reports the following:

  WARNING: struct kgdb_arch should normally be const
  #28: FILE: arch/mips/kernel/kgdb.c:397:
  +struct kgdb_arch arch_kgdb_ops = {

This report makes sense, as all other ops struct, this
one should also be const. This patch does the change.

Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 v2: Added CCs to all maintainers/supporters identified by get_maintainer.pl and Acks from Daniel and Paul.

 arch/arc/kernel/kgdb.c        | 2 +-
 arch/arm/kernel/kgdb.c        | 2 +-
 arch/arm64/kernel/kgdb.c      | 2 +-
 arch/h8300/kernel/kgdb.c      | 2 +-
 arch/hexagon/kernel/kgdb.c    | 2 +-
 arch/microblaze/kernel/kgdb.c | 2 +-
 arch/mips/kernel/kgdb.c       | 2 +-
 arch/nios2/kernel/kgdb.c      | 2 +-
 arch/powerpc/kernel/kgdb.c    | 2 +-
 arch/sh/kernel/kgdb.c         | 2 +-
 arch/sparc/kernel/kgdb_32.c   | 2 +-
 arch/sparc/kernel/kgdb_64.c   | 2 +-
 arch/x86/kernel/kgdb.c        | 2 +-
 include/linux/kgdb.h          | 2 +-
 14 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/arc/kernel/kgdb.c b/arch/arc/kernel/kgdb.c
index 9a3c34af2ae8..bfd04b442e36 100644
--- a/arch/arc/kernel/kgdb.c
+++ b/arch/arc/kernel/kgdb.c
@@ -204,7 +204,7 @@ void kgdb_roundup_cpus(unsigned long flags)
 	local_irq_disable();
 }
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 	/* breakpoint instruction: TRAP_S 0x3 */
 #ifdef CONFIG_CPU_BIG_ENDIAN
 	.gdb_bpt_instr		= {0x78, 0x7e},
diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
index caa0dbe3dc61..21a6d5958955 100644
--- a/arch/arm/kernel/kgdb.c
+++ b/arch/arm/kernel/kgdb.c
@@ -274,7 +274,7 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
  * and we handle the normal undef case within the do_undefinstr
  * handler.
  */
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 #ifndef __ARMEB__
 	.gdb_bpt_instr		= {0xfe, 0xde, 0xff, 0xe7}
 #else /* ! __ARMEB__ */
diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
index a20de58061a8..fe1d1f935b90 100644
--- a/arch/arm64/kernel/kgdb.c
+++ b/arch/arm64/kernel/kgdb.c
@@ -357,7 +357,7 @@ void kgdb_arch_exit(void)
 	unregister_die_notifier(&kgdb_notifier);
 }
 
-struct kgdb_arch arch_kgdb_ops;
+const struct kgdb_arch arch_kgdb_ops;
 
 int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt)
 {
diff --git a/arch/h8300/kernel/kgdb.c b/arch/h8300/kernel/kgdb.c
index 1a1d30cb0609..602e478afbd5 100644
--- a/arch/h8300/kernel/kgdb.c
+++ b/arch/h8300/kernel/kgdb.c
@@ -129,7 +129,7 @@ void kgdb_arch_exit(void)
 	/* Nothing to do */
 }
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 	/* Breakpoint instruction: trapa #2 */
 	.gdb_bpt_instr = { 0x57, 0x20 },
 };
diff --git a/arch/hexagon/kernel/kgdb.c b/arch/hexagon/kernel/kgdb.c
index 16c24b22d0b2..f1924d483e78 100644
--- a/arch/hexagon/kernel/kgdb.c
+++ b/arch/hexagon/kernel/kgdb.c
@@ -83,7 +83,7 @@ struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
 	{ "syscall_nr", GDB_SIZEOF_REG, offsetof(struct pt_regs, syscall_nr)},
 };
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 	/* trap0(#0xDB) 0x0cdb0054 */
 	.gdb_bpt_instr = {0x54, 0x00, 0xdb, 0x0c},
 };
diff --git a/arch/microblaze/kernel/kgdb.c b/arch/microblaze/kernel/kgdb.c
index 6366f69d118e..130cd0f064ce 100644
--- a/arch/microblaze/kernel/kgdb.c
+++ b/arch/microblaze/kernel/kgdb.c
@@ -143,7 +143,7 @@ void kgdb_arch_exit(void)
 /*
  * Global data
  */
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 #ifdef __MICROBLAZEEL__
 	.gdb_bpt_instr = {0x18, 0x00, 0x0c, 0xba}, /* brki r16, 0x18 */
 #else
diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c
index 31eff1bec577..edfdc2ec2d16 100644
--- a/arch/mips/kernel/kgdb.c
+++ b/arch/mips/kernel/kgdb.c
@@ -394,7 +394,7 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
 	return -1;
 }
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 #ifdef CONFIG_CPU_BIG_ENDIAN
 	.gdb_bpt_instr = { spec_op << 2, 0x00, 0x00, break_op },
 #else
diff --git a/arch/nios2/kernel/kgdb.c b/arch/nios2/kernel/kgdb.c
index 117859122d1c..37b25f844a2d 100644
--- a/arch/nios2/kernel/kgdb.c
+++ b/arch/nios2/kernel/kgdb.c
@@ -165,7 +165,7 @@ void kgdb_arch_exit(void)
 	/* Nothing to do */
 }
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 	/* Breakpoint instruction: trap 30 */
 	.gdb_bpt_instr = { 0xba, 0x6f, 0x3b, 0x00 },
 };
diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index 59c578f865aa..bdb588b1d8fb 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -477,7 +477,7 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
 /*
  * Global data
  */
-struct kgdb_arch arch_kgdb_ops;
+const struct kgdb_arch arch_kgdb_ops;
 
 static int kgdb_not_implemented(struct pt_regs *regs)
 {
diff --git a/arch/sh/kernel/kgdb.c b/arch/sh/kernel/kgdb.c
index 4f04c6638a4d..a24c48446e98 100644
--- a/arch/sh/kernel/kgdb.c
+++ b/arch/sh/kernel/kgdb.c
@@ -382,7 +382,7 @@ void kgdb_arch_exit(void)
 	unregister_die_notifier(&kgdb_notifier);
 }
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 	/* Breakpoint instruction: trapa #0x3c */
 #ifdef CONFIG_CPU_LITTLE_ENDIAN
 	.gdb_bpt_instr		= { 0x3c, 0xc3 },
diff --git a/arch/sparc/kernel/kgdb_32.c b/arch/sparc/kernel/kgdb_32.c
index 639c8e54530a..7580775a14b9 100644
--- a/arch/sparc/kernel/kgdb_32.c
+++ b/arch/sparc/kernel/kgdb_32.c
@@ -166,7 +166,7 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
 	regs->npc = regs->pc + 4;
 }
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 	/* Breakpoint instruction: ta 0x7d */
 	.gdb_bpt_instr		= { 0x91, 0xd0, 0x20, 0x7d },
 };
diff --git a/arch/sparc/kernel/kgdb_64.c b/arch/sparc/kernel/kgdb_64.c
index a68bbddbdba4..5d6c2d287e85 100644
--- a/arch/sparc/kernel/kgdb_64.c
+++ b/arch/sparc/kernel/kgdb_64.c
@@ -195,7 +195,7 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
 	regs->tnpc = regs->tpc + 4;
 }
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 	/* Breakpoint instruction: ta 0x72 */
 	.gdb_bpt_instr		= { 0x91, 0xd0, 0x20, 0x72 },
 };
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index 8e36f249646e..e7effc02f13c 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -804,7 +804,7 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
 				  (char *)bpt->saved_instr, BREAK_INSTR_SIZE);
 }
 
-struct kgdb_arch arch_kgdb_ops = {
+const struct kgdb_arch arch_kgdb_ops = {
 	/* Breakpoint instruction: */
 	.gdb_bpt_instr		= { 0xcc },
 	.flags			= KGDB_HW_BREAKPOINT,
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index e465bb15912d..3bf313311cca 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -281,7 +281,7 @@ struct kgdb_io {
 	int			is_console;
 };
 
-extern struct kgdb_arch		arch_kgdb_ops;
+extern const struct kgdb_arch		arch_kgdb_ops;
 
 extern unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs);
 
-- 
2.13.3

Re: [PATCH v2 2/2] kgdb/treewide: constify struct kgdb_arch arch_kgdb_ops

[Borislav Petkov]

On Thu, Dec 06, 2018 at 08:07:40PM +0000, Christophe Leroy wrote:
> checkpatch.pl reports the following:
> 
>   WARNING: struct kgdb_arch should normally be const
>   #28: FILE: arch/mips/kernel/kgdb.c:397:
>   +struct kgdb_arch arch_kgdb_ops = {
> 
> This report makes sense, as all other ops struct, this
> one should also be const. This patch does the change.
> 
> Cc: Vineet Gupta <vgupta@synopsys.com>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will.deacon@arm.com>
> Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
> Cc: Richard Kuo <rkuo@codeaurora.org>
> Cc: Michal Simek <monstr@monstr.eu>
> Cc: Ralf Baechle <ralf@linux-mips.org>
> Cc: Paul Burton <paul.burton@mips.com>
> Cc: James Hogan <jhogan@kernel.org>
> Cc: Ley Foon Tan <lftan@altera.com>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Rich Felker <dalias@libc.org>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: x86@kernel.org
> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
> Acked-by: Paul Burton <paul.burton@mips.com>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> ---
>  v2: Added CCs to all maintainers/supporters identified by get_maintainer.pl and Acks from Daniel and Paul.
> 
>  arch/arc/kernel/kgdb.c        | 2 +-
>  arch/arm/kernel/kgdb.c        | 2 +-
>  arch/arm64/kernel/kgdb.c      | 2 +-
>  arch/h8300/kernel/kgdb.c      | 2 +-
>  arch/hexagon/kernel/kgdb.c    | 2 +-
>  arch/microblaze/kernel/kgdb.c | 2 +-
>  arch/mips/kernel/kgdb.c       | 2 +-
>  arch/nios2/kernel/kgdb.c      | 2 +-
>  arch/powerpc/kernel/kgdb.c    | 2 +-
>  arch/sh/kernel/kgdb.c         | 2 +-
>  arch/sparc/kernel/kgdb_32.c   | 2 +-
>  arch/sparc/kernel/kgdb_64.c   | 2 +-
>  arch/x86/kernel/kgdb.c        | 2 +-
>  include/linux/kgdb.h          | 2 +-
>  14 files changed, 14 insertions(+), 14 deletions(-)

...

> diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
> index 8e36f249646e..e7effc02f13c 100644
> --- a/arch/x86/kernel/kgdb.c
> +++ b/arch/x86/kernel/kgdb.c
> @@ -804,7 +804,7 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
>  				  (char *)bpt->saved_instr, BREAK_INSTR_SIZE);
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* Breakpoint instruction: */
>  	.gdb_bpt_instr		= { 0xcc },
>  	.flags			= KGDB_HW_BREAKPOINT,

For the x86 bits:

Acked-by: Borislav Petkov <bp@suse.de>

-- 
Regards/Gruss,
    Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.

Re: [PATCH v2 2/2] kgdb/treewide: constify struct kgdb_arch arch_kgdb_ops

[Michael Ellerman]

Christophe Leroy <christophe.leroy@c-s.fr> writes:

> checkpatch.pl reports the following:
>
>   WARNING: struct kgdb_arch should normally be const
>   #28: FILE: arch/mips/kernel/kgdb.c:397:
>   +struct kgdb_arch arch_kgdb_ops = {
>
> This report makes sense, as all other ops struct, this
> one should also be const. This patch does the change.
...

> diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
> index 59c578f865aa..bdb588b1d8fb 100644
> --- a/arch/powerpc/kernel/kgdb.c
> +++ b/arch/powerpc/kernel/kgdb.c
> @@ -477,7 +477,7 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
>  /*
>   * Global data
>   */
> -struct kgdb_arch arch_kgdb_ops;
> +const struct kgdb_arch arch_kgdb_ops;
>  
>  static int kgdb_not_implemented(struct pt_regs *regs)
>  {

Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

cheers

Re: [PATCH v2 2/2] kgdb/treewide: constify struct kgdb_arch arch_kgdb_ops

[Daniel Thompson]

On Thu, Dec 06, 2018 at 08:07:40PM +0000, Christophe Leroy wrote:
> checkpatch.pl reports the following:
> 
>   WARNING: struct kgdb_arch should normally be const
>   #28: FILE: arch/mips/kernel/kgdb.c:397:
>   +struct kgdb_arch arch_kgdb_ops = {
> 
> This report makes sense, as all other ops struct, this
> one should also be const. This patch does the change.
> 
> Cc: Vineet Gupta <vgupta@synopsys.com>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will.deacon@arm.com>
> Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
> Cc: Richard Kuo <rkuo@codeaurora.org>
> Cc: Michal Simek <monstr@monstr.eu>
> Cc: Ralf Baechle <ralf@linux-mips.org>
> Cc: Paul Burton <paul.burton@mips.com>
> Cc: James Hogan <jhogan@kernel.org>
> Cc: Ley Foon Tan <lftan@altera.com>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Rich Felker <dalias@libc.org>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: x86@kernel.org
> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
> Acked-by: Paul Burton <paul.burton@mips.com>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

I've not heard any objections from the arch/ maintainers so...

Applied! Thanks.


> -
> ---
>  v2: Added CCs to all maintainers/supporters identified by get_maintainer.pl and Acks from Daniel and Paul.
> 
>  arch/arc/kernel/kgdb.c        | 2 +-
>  arch/arm/kernel/kgdb.c        | 2 +-
>  arch/arm64/kernel/kgdb.c      | 2 +-
>  arch/h8300/kernel/kgdb.c      | 2 +-
>  arch/hexagon/kernel/kgdb.c    | 2 +-
>  arch/microblaze/kernel/kgdb.c | 2 +-
>  arch/mips/kernel/kgdb.c       | 2 +-
>  arch/nios2/kernel/kgdb.c      | 2 +-
>  arch/powerpc/kernel/kgdb.c    | 2 +-
>  arch/sh/kernel/kgdb.c         | 2 +-
>  arch/sparc/kernel/kgdb_32.c   | 2 +-
>  arch/sparc/kernel/kgdb_64.c   | 2 +-
>  arch/x86/kernel/kgdb.c        | 2 +-
>  include/linux/kgdb.h          | 2 +-
>  14 files changed, 14 insertions(+), 14 deletions(-)
> 
> diff --git a/arch/arc/kernel/kgdb.c b/arch/arc/kernel/kgdb.c
> index 9a3c34af2ae8..bfd04b442e36 100644
> --- a/arch/arc/kernel/kgdb.c
> +++ b/arch/arc/kernel/kgdb.c
> @@ -204,7 +204,7 @@ void kgdb_roundup_cpus(unsigned long flags)
>  	local_irq_disable();
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* breakpoint instruction: TRAP_S 0x3 */
>  #ifdef CONFIG_CPU_BIG_ENDIAN
>  	.gdb_bpt_instr		= {0x78, 0x7e},
> diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
> index caa0dbe3dc61..21a6d5958955 100644
> --- a/arch/arm/kernel/kgdb.c
> +++ b/arch/arm/kernel/kgdb.c
> @@ -274,7 +274,7 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
>   * and we handle the normal undef case within the do_undefinstr
>   * handler.
>   */
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  #ifndef __ARMEB__
>  	.gdb_bpt_instr		= {0xfe, 0xde, 0xff, 0xe7}
>  #else /* ! __ARMEB__ */
> diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
> index a20de58061a8..fe1d1f935b90 100644
> --- a/arch/arm64/kernel/kgdb.c
> +++ b/arch/arm64/kernel/kgdb.c
> @@ -357,7 +357,7 @@ void kgdb_arch_exit(void)
>  	unregister_die_notifier(&kgdb_notifier);
>  }
>  
> -struct kgdb_arch arch_kgdb_ops;
> +const struct kgdb_arch arch_kgdb_ops;
>  
>  int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt)
>  {
> diff --git a/arch/h8300/kernel/kgdb.c b/arch/h8300/kernel/kgdb.c
> index 1a1d30cb0609..602e478afbd5 100644
> --- a/arch/h8300/kernel/kgdb.c
> +++ b/arch/h8300/kernel/kgdb.c
> @@ -129,7 +129,7 @@ void kgdb_arch_exit(void)
>  	/* Nothing to do */
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* Breakpoint instruction: trapa #2 */
>  	.gdb_bpt_instr = { 0x57, 0x20 },
>  };
> diff --git a/arch/hexagon/kernel/kgdb.c b/arch/hexagon/kernel/kgdb.c
> index 16c24b22d0b2..f1924d483e78 100644
> --- a/arch/hexagon/kernel/kgdb.c
> +++ b/arch/hexagon/kernel/kgdb.c
> @@ -83,7 +83,7 @@ struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
>  	{ "syscall_nr", GDB_SIZEOF_REG, offsetof(struct pt_regs, syscall_nr)},
>  };
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* trap0(#0xDB) 0x0cdb0054 */
>  	.gdb_bpt_instr = {0x54, 0x00, 0xdb, 0x0c},
>  };
> diff --git a/arch/microblaze/kernel/kgdb.c b/arch/microblaze/kernel/kgdb.c
> index 6366f69d118e..130cd0f064ce 100644
> --- a/arch/microblaze/kernel/kgdb.c
> +++ b/arch/microblaze/kernel/kgdb.c
> @@ -143,7 +143,7 @@ void kgdb_arch_exit(void)
>  /*
>   * Global data
>   */
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  #ifdef __MICROBLAZEEL__
>  	.gdb_bpt_instr = {0x18, 0x00, 0x0c, 0xba}, /* brki r16, 0x18 */
>  #else
> diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c
> index 31eff1bec577..edfdc2ec2d16 100644
> --- a/arch/mips/kernel/kgdb.c
> +++ b/arch/mips/kernel/kgdb.c
> @@ -394,7 +394,7 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
>  	return -1;
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  #ifdef CONFIG_CPU_BIG_ENDIAN
>  	.gdb_bpt_instr = { spec_op << 2, 0x00, 0x00, break_op },
>  #else
> diff --git a/arch/nios2/kernel/kgdb.c b/arch/nios2/kernel/kgdb.c
> index 117859122d1c..37b25f844a2d 100644
> --- a/arch/nios2/kernel/kgdb.c
> +++ b/arch/nios2/kernel/kgdb.c
> @@ -165,7 +165,7 @@ void kgdb_arch_exit(void)
>  	/* Nothing to do */
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* Breakpoint instruction: trap 30 */
>  	.gdb_bpt_instr = { 0xba, 0x6f, 0x3b, 0x00 },
>  };
> diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
> index 59c578f865aa..bdb588b1d8fb 100644
> --- a/arch/powerpc/kernel/kgdb.c
> +++ b/arch/powerpc/kernel/kgdb.c
> @@ -477,7 +477,7 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
>  /*
>   * Global data
>   */
> -struct kgdb_arch arch_kgdb_ops;
> +const struct kgdb_arch arch_kgdb_ops;
>  
>  static int kgdb_not_implemented(struct pt_regs *regs)
>  {
> diff --git a/arch/sh/kernel/kgdb.c b/arch/sh/kernel/kgdb.c
> index 4f04c6638a4d..a24c48446e98 100644
> --- a/arch/sh/kernel/kgdb.c
> +++ b/arch/sh/kernel/kgdb.c
> @@ -382,7 +382,7 @@ void kgdb_arch_exit(void)
>  	unregister_die_notifier(&kgdb_notifier);
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* Breakpoint instruction: trapa #0x3c */
>  #ifdef CONFIG_CPU_LITTLE_ENDIAN
>  	.gdb_bpt_instr		= { 0x3c, 0xc3 },
> diff --git a/arch/sparc/kernel/kgdb_32.c b/arch/sparc/kernel/kgdb_32.c
> index 639c8e54530a..7580775a14b9 100644
> --- a/arch/sparc/kernel/kgdb_32.c
> +++ b/arch/sparc/kernel/kgdb_32.c
> @@ -166,7 +166,7 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
>  	regs->npc = regs->pc + 4;
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* Breakpoint instruction: ta 0x7d */
>  	.gdb_bpt_instr		= { 0x91, 0xd0, 0x20, 0x7d },
>  };
> diff --git a/arch/sparc/kernel/kgdb_64.c b/arch/sparc/kernel/kgdb_64.c
> index a68bbddbdba4..5d6c2d287e85 100644
> --- a/arch/sparc/kernel/kgdb_64.c
> +++ b/arch/sparc/kernel/kgdb_64.c
> @@ -195,7 +195,7 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
>  	regs->tnpc = regs->tpc + 4;
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* Breakpoint instruction: ta 0x72 */
>  	.gdb_bpt_instr		= { 0x91, 0xd0, 0x20, 0x72 },
>  };
> diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
> index 8e36f249646e..e7effc02f13c 100644
> --- a/arch/x86/kernel/kgdb.c
> +++ b/arch/x86/kernel/kgdb.c
> @@ -804,7 +804,7 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
>  				  (char *)bpt->saved_instr, BREAK_INSTR_SIZE);
>  }
>  
> -struct kgdb_arch arch_kgdb_ops = {
> +const struct kgdb_arch arch_kgdb_ops = {
>  	/* Breakpoint instruction: */
>  	.gdb_bpt_instr		= { 0xcc },
>  	.flags			= KGDB_HW_BREAKPOINT,
> diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
> index e465bb15912d..3bf313311cca 100644
> --- a/include/linux/kgdb.h
> +++ b/include/linux/kgdb.h
> @@ -281,7 +281,7 @@ struct kgdb_io {
>  	int			is_console;
>  };
>  
> -extern struct kgdb_arch		arch_kgdb_ops;
> +extern const struct kgdb_arch		arch_kgdb_ops;
>  
>  extern unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs);
>  
> -- 
> 2.13.3
> 

Re: [PATCH v2 1/2] mips/kgdb: prepare arch_kgdb_ops for constness

[Daniel Thompson]

On Thu, Dec 06, 2018 at 08:07:38PM +0000, Christophe Leroy wrote:
> MIPS is the only architecture modifying arch_kgdb_ops during init.
> This patch makes the init static, so that it can be changed to
> const in following patch, as recommended by checkpatch.pl
> 
> Suggested-by: Paul Burton <paul.burton@mips.com>
> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
> Acked-by: Paul Burton <paul.burton@mips.com>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

Applied! Thanks.


> -
> ---
>  v2: Added acks from Daniel and Paul.
> 
>  arch/mips/kernel/kgdb.c | 16 +++++++---------
>  1 file changed, 7 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c
> index eb6c0d582626..31eff1bec577 100644
> --- a/arch/mips/kernel/kgdb.c
> +++ b/arch/mips/kernel/kgdb.c
> @@ -394,18 +394,16 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
>  	return -1;
>  }
>  
> -struct kgdb_arch arch_kgdb_ops;
> +struct kgdb_arch arch_kgdb_ops = {
> +#ifdef CONFIG_CPU_BIG_ENDIAN
> +	.gdb_bpt_instr = { spec_op << 2, 0x00, 0x00, break_op },
> +#else
> +	.gdb_bpt_instr = { break_op, 0x00, 0x00, spec_op << 2 },
> +#endif
> +};
>  
>  int kgdb_arch_init(void)
>  {
> -	union mips_instruction insn = {
> -		.r_format = {
> -			.opcode = spec_op,
> -			.func	= break_op,
> -		}
> -	};
> -	memcpy(arch_kgdb_ops.gdb_bpt_instr, insn.byte, BREAK_INSTR_SIZE);
> -
>  	register_die_notifier(&kgdb_notifier);
>  
>  	return 0;
> -- 
> 2.13.3
>