[PATCH 1/3] kprobes: introduce weak variant of kprobe_exceptions_notify

[PATCH 1/3] kprobes: introduce weak variant of kprobe_exceptions_notify

[Naveen N. Rao]

kprobe_exceptions_notify() is not used on some of the architectures such
as arm[64] and powerpc anymore. Introduce a weak variant for such
architectures.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 kernel/kprobes.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 43460104f119..60a702a05684 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1705,6 +1705,12 @@ void unregister_kprobes(struct kprobe **kps, int num)
 }
 EXPORT_SYMBOL_GPL(unregister_kprobes);
 
+int __weak __kprobes kprobe_exceptions_notify(struct notifier_block *self,
+					      unsigned long val, void *data)
+{
+	return NOTIFY_DONE;
+}
+
 static struct notifier_block kprobe_exceptions_nb = {
 	.notifier_call = kprobe_exceptions_notify,
 	.priority = 0x7fffffff /* we need to be notified first */
-- 
2.11.0

[PATCH 2/3] arm: kprobes: remove kprobe_exceptions_notify

[Naveen N. Rao]

... as the weak variant will do.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/arm/probes/kprobes/core.c     | 10 ----------
 arch/arm64/kernel/probes/kprobes.c |  6 ------
 2 files changed, 16 deletions(-)

diff --git a/arch/arm/probes/kprobes/core.c b/arch/arm/probes/kprobes/core.c
index a4ec240ee7ba..f89db1e278cf 100644
--- a/arch/arm/probes/kprobes/core.c
+++ b/arch/arm/probes/kprobes/core.c
@@ -391,16 +391,6 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr)
 	return 0;
 }
 
-int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
-				       unsigned long val, void *data)
-{
-	/*
-	 * notify_die() is currently never called on ARM,
-	 * so this callback is currently empty.
-	 */
-	return NOTIFY_DONE;
-}
-
 /*
  * When a retprobed function returns, trampoline_handler() is called,
  * calling the kretprobe's handler. We construct a struct pt_regs to
diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index f0593c92279b..769becae3e90 100644
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/arch/arm64/kernel/probes/kprobes.c
@@ -371,12 +371,6 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr)
 	return 0;
 }
 
-int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
-				       unsigned long val, void *data)
-{
-	return NOTIFY_DONE;
-}
-
 static void __kprobes kprobe_handler(struct pt_regs *regs)
 {
 	struct kprobe *p, *cur_kprobe;
-- 
2.11.0

Re: [PATCH 2/3] arm: kprobes: remove kprobe_exceptions_notify

[Naveen N. Rao]

On 2017/02/08 01:24AM, Naveen N Rao wrote:
> ... as the weak variant will do.
> 
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> ---
>  arch/arm/probes/kprobes/core.c     | 10 ----------
>  arch/arm64/kernel/probes/kprobes.c |  6 ------
>  2 files changed, 16 deletions(-)

With the generic changes in this series now in -rc1, can you please pick 
this up?

Thanks,
Naveen

Re: [PATCH 2/3] arm: kprobes: remove kprobe_exceptions_notify

[Russell King - ARM Linux]

On Mon, Mar 06, 2017 at 11:37:20PM +0530, Naveen N. Rao wrote:
> On 2017/02/08 01:24AM, Naveen N Rao wrote:
> > ... as the weak variant will do.
> > 
> > Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> > ---
> >  arch/arm/probes/kprobes/core.c     | 10 ----------
> >  arch/arm64/kernel/probes/kprobes.c |  6 ------
> >  2 files changed, 16 deletions(-)
> 
> With the generic changes in this series now in -rc1, can you please pick 
> this up?

It would've been nice to have been in the To: or Cc: on this patch,
I suspect everyone on the ARM side ignored this series (I certainly
didn't notice it, and I suspect the ARM64 folk didn't notice it for
exactly the same reason.)

In any case, this patch needs to be split - ARM and ARM64 are
maintained separately (as stated in MAINTAINERS), and patches go via
different trees.  Please resubmit with the patch split between the
architectures and proper recipients in the headers.

Thanks.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.

[PATCH 3/3] powerpc: kprobes: remove kprobe_exceptions_notify()

[Naveen N. Rao]

... as the weak variant will do.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/kprobes.c | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 45e4f82b230d..fce05a38851c 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -475,15 +475,6 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
 	return 0;
 }
 
-/*
- * Wrapper routine to for handling exceptions.
- */
-int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
-				       unsigned long val, void *data)
-{
-	return NOTIFY_DONE;
-}
-
 unsigned long arch_deref_entry_point(void *entry)
 {
 	return ppc_global_function_entry(entry);
-- 
2.11.0

Re: [3/3] powerpc: kprobes: remove kprobe_exceptions_notify()

[Michael Ellerman]

On Tue, 2017-02-07 at 19:54:16 UTC, "Naveen N. Rao" wrote:
> ... as the weak variant will do.
> 
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/0ddde5004d26c483c9e67005b2be5b

cheers

Re: [PATCH 1/3] kprobes: introduce weak variant of kprobe_exceptions_notify

[Masami Hiramatsu]

On Wed,  8 Feb 2017 01:24:14 +0530
"Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote:

> kprobe_exceptions_notify() is not used on some of the architectures such
> as arm[64] and powerpc anymore. Introduce a weak variant for such
> architectures.
> 

Good catch!

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>

for all patches in this series.

Thank you!

> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> ---
>  kernel/kprobes.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index 43460104f119..60a702a05684 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -1705,6 +1705,12 @@ void unregister_kprobes(struct kprobe **kps, int num)
>  }
>  EXPORT_SYMBOL_GPL(unregister_kprobes);
>  
> +int __weak __kprobes kprobe_exceptions_notify(struct notifier_block *self,
> +					      unsigned long val, void *data)
> +{
> +	return NOTIFY_DONE;
> +}
> +
>  static struct notifier_block kprobe_exceptions_nb = {
>  	.notifier_call = kprobe_exceptions_notify,
>  	.priority = 0x7fffffff /* we need to be notified first */
> -- 
> 2.11.0
> 


-- 
Masami Hiramatsu <mhiramat@kernel.org>

Re: [PATCH 1/3] kprobes: introduce weak variant of kprobe_exceptions_notify

[Michael Ellerman]

"Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> writes:

> kprobe_exceptions_notify() is not used on some of the architectures such
> as arm[64] and powerpc anymore. Introduce a weak variant for such
> architectures.

I'll merge patch 1 & 3 via the powerpc tree for v4.11.

You can then send patch 2 to the arm guys after -rc1, or for 4.12.

cheers

Re: [PATCH 1/3] kprobes: introduce weak variant of kprobe_exceptions_notify

[Ingo Molnar]

* Michael Ellerman <mpe@ellerman.id.au> wrote:

> "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> writes:
> 
> > kprobe_exceptions_notify() is not used on some of the architectures such
> > as arm[64] and powerpc anymore. Introduce a weak variant for such
> > architectures.
> 
> I'll merge patch 1 & 3 via the powerpc tree for v4.11.

Acked-by: Ingo Molnar <mingo@kernel.org>

Thanks,

	Ingo

Re: [PATCH 1/3] kprobes: introduce weak variant of kprobe_exceptions_notify

[Naveen N. Rao]

On 2017/02/10 02:41PM, Michael Ellerman wrote:
> "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> writes:
> 
> > kprobe_exceptions_notify() is not used on some of the architectures such
> > as arm[64] and powerpc anymore. Introduce a weak variant for such
> > architectures.
> 
> I'll merge patch 1 & 3 via the powerpc tree for v4.11.
> 
> You can then send patch 2 to the arm guys after -rc1, or for 4.12.

Sure, thanks!

- Naveen

Re: [1/3] kprobes: introduce weak variant of kprobe_exceptions_notify

[Michael Ellerman]

On Tue, 2017-02-07 at 19:54:14 UTC, "Naveen N. Rao" wrote:
> kprobe_exceptions_notify() is not used on some of the architectures such
> as arm[64] and powerpc anymore. Introduce a weak variant for such
> architectures.
> 
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> Acked-by: Masami Hiramatsu <mhiramat@kernel.org>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/fc62d0207ae0ebc9d19df68394c0dc

cheers