diff mbox series

[V4,13/20] rv/reactor: Add the panic reactor

Message ID 67e522ab57e64eee313af508a8c70f3cce33e525.1655368610.git.bristot@kernel.org (mailing list archive)
State Superseded
Headers show
Series The Runtime Verification (RV) interface | expand

Commit Message

Daniel Bristot de Oliveira June 16, 2022, 8:44 a.m. UTC 
Sample reactor that panics the system when an exception is found. This
is useful both to capture a vmcore, or to fail-safe a critical system.

Cc: Wim Van Sebroeck <wim@linux-watchdog.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Gabriele Paoloni <gpaoloni@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
---
 kernel/trace/rv/Kconfig         |  8 ++++++
 kernel/trace/rv/Makefile        |  1 +
 kernel/trace/rv/reactor_panic.c | 44 +++++++++++++++++++++++++++++++++
 3 files changed, 53 insertions(+)
 create mode 100644 kernel/trace/rv/reactor_panic.c

Comments

kernel test robot June 16, 2022, 3:20 p.m. UTC | #1 
Hi Daniel,

I love your patch! Perhaps something to improve:

[auto build test WARNING on rostedt-trace/for-next]
[also build test WARNING on tip/sched/core]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Daniel-Bristot-de-Oliveira/The-Runtime-Verification-RV-interface/20220616-164837
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git for-next
config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20220616/202206162325.aggB6gj9-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
reproduce (this is a W=1 build):
        # https://github.com/intel-lab-lkp/linux/commit/c32f84c1978c0e0b8526da45a2ab87e191246f68
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Daniel-Bristot-de-Oliveira/The-Runtime-Verification-RV-interface/20220616-164837
        git checkout c32f84c1978c0e0b8526da45a2ab87e191246f68
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash kernel/trace/rv/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> kernel/trace/rv/reactor_panic.c:28:5: warning: no previous prototype for 'register_react_panic' [-Wmissing-prototypes]
      28 | int register_react_panic(void)
         |     ^~~~~~~~~~~~~~~~~~~~
>> kernel/trace/rv/reactor_panic.c:34:6: warning: no previous prototype for 'unregister_react_panic' [-Wmissing-prototypes]
      34 | void unregister_react_panic(void)
         |      ^~~~~~~~~~~~~~~~~~~~~~


vim +/register_react_panic +28 kernel/trace/rv/reactor_panic.c

    27	
  > 28	int register_react_panic(void)
    29	{
    30		rv_register_reactor(&rv_panic);
    31		return 0;
    32	}
    33	
  > 34	void unregister_react_panic(void)
    35	{
    36		rv_unregister_reactor(&rv_panic);
    37	}
    38
Randy Dunlap June 16, 2022, 9:03 p.m. UTC | #2 
On 6/16/22 01:44, Daniel Bristot de Oliveira wrote:
> diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig
> index be8e3dab0a52..91a17b13a080 100644
> --- a/kernel/trace/rv/Kconfig
> +++ b/kernel/trace/rv/Kconfig
> @@ -60,4 +60,12 @@ config RV_REACT_PRINTK
>  	  Enables the printk reactor. The printk reactor emmits a printk()

	                                                 emits

>  	  message if an exception is found.
>  
> +config RV_REACT_PANIC
> +	bool "Panic reactor"
> +	depends on RV_REACTORS
> +	default y if RV_REACTORS
> +	help
> +	  Enables the panic reactor. The panic reactor emmits a printk()

	                                               emits

> +	  message if an exception is found and panic()s the system.
Daniel Bristot de Oliveira June 17, 2022, 4:09 p.m. UTC | #3 
On 6/16/22 23:03, Randy Dunlap wrote:
> 
> 
> On 6/16/22 01:44, Daniel Bristot de Oliveira wrote:
>> diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig
>> index be8e3dab0a52..91a17b13a080 100644
>> --- a/kernel/trace/rv/Kconfig
>> +++ b/kernel/trace/rv/Kconfig
>> @@ -60,4 +60,12 @@ config RV_REACT_PRINTK
>>  	  Enables the printk reactor. The printk reactor emmits a printk()
> 
> 	                                                 emits

oops!
>>  	  message if an exception is found.
>>  
>> +config RV_REACT_PANIC
>> +	bool "Panic reactor"
>> +	depends on RV_REACTORS
>> +	default y if RV_REACTORS
>> +	help
>> +	  Enables the panic reactor. The panic reactor emmits a printk()
> 
> 	                                               emits

and Oops again.

>> +	  message if an exception is found and panic()s the system.
> 

I will fix that, thanks Randy!
-- Daniel
Steven Rostedt June 28, 2022, 7:06 p.m. UTC | #4 
On Thu, 16 Jun 2022 10:44:55 +0200
Daniel Bristot de Oliveira <bristot@kernel.org> wrote:

> Sample reactor that panics the system when an exception is found. This
> is useful both to capture a vmcore, or to fail-safe a critical system.
> 
> Cc: Wim Van Sebroeck <wim@linux-watchdog.org>
> Cc: Guenter Roeck <linux@roeck-us.net>
> Cc: Jonathan Corbet <corbet@lwn.net>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Will Deacon <will@kernel.org>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Marco Elver <elver@google.com>
> Cc: Dmitry Vyukov <dvyukov@google.com>
> Cc: "Paul E. McKenney" <paulmck@kernel.org>
> Cc: Shuah Khan <skhan@linuxfoundation.org>
> Cc: Gabriele Paoloni <gpaoloni@redhat.com>
> Cc: Juri Lelli <juri.lelli@redhat.com>
> Cc: Clark Williams <williams@redhat.com>
> Cc: linux-doc@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-trace-devel@vger.kernel.org
> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
> ---
>  kernel/trace/rv/Kconfig         |  8 ++++++
>  kernel/trace/rv/Makefile        |  1 +
>  kernel/trace/rv/reactor_panic.c | 44 +++++++++++++++++++++++++++++++++
>  3 files changed, 53 insertions(+)
>  create mode 100644 kernel/trace/rv/reactor_panic.c
> 
> diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig
> index be8e3dab0a52..91a17b13a080 100644
> --- a/kernel/trace/rv/Kconfig
> +++ b/kernel/trace/rv/Kconfig
> @@ -60,4 +60,12 @@ config RV_REACT_PRINTK
>  	  Enables the printk reactor. The printk reactor emmits a printk()
>  	  message if an exception is found.
>  
> +config RV_REACT_PANIC
> +	bool "Panic reactor"
> +	depends on RV_REACTORS
> +	default y if RV_REACTORS

Just put default y if it already depends on RV_REACTORS.

-- Steve

> +	help
> +	  Enables the panic reactor. The panic reactor emmits a printk()
> +	  message if an exception is found and panic()s the system.
> +
>  endif # RV
> diff --git a/kernel/trace/rv/Makefile b/kernel/trace/rv/Makefile
Daniel Bristot de Oliveira July 13, 2022, 6:47 p.m. UTC | #5 
On 6/16/22 23:03, Randy Dunlap wrote:
>>  	  Enables the printk reactor. The printk reactor emmits a printk()
> 	                                                 emits
> 

Fixed all the cases!

-- Daniel
diff mbox series

Patch

diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig
index be8e3dab0a52..91a17b13a080 100644
--- a/kernel/trace/rv/Kconfig
+++ b/kernel/trace/rv/Kconfig
@@ -60,4 +60,12 @@  config RV_REACT_PRINTK
 	  Enables the printk reactor. The printk reactor emmits a printk()
 	  message if an exception is found.
 
+config RV_REACT_PANIC
+	bool "Panic reactor"
+	depends on RV_REACTORS
+	default y if RV_REACTORS
+	help
+	  Enables the panic reactor. The panic reactor emmits a printk()
+	  message if an exception is found and panic()s the system.
+
 endif # RV
diff --git a/kernel/trace/rv/Makefile b/kernel/trace/rv/Makefile
index a13c750a35c1..963d14875b45 100644
--- a/kernel/trace/rv/Makefile
+++ b/kernel/trace/rv/Makefile
@@ -5,3 +5,4 @@  obj-$(CONFIG_RV_MON_WIP) += monitors/wip/wip.o
 obj-$(CONFIG_RV_MON_WWNR) += monitors/wwnr/wwnr.o
 obj-$(CONFIG_RV_REACTORS) += rv_reactors.o
 obj-$(CONFIG_RV_REACT_PRINTK) += reactor_printk.o
+obj-$(CONFIG_RV_REACT_PANIC) += reactor_panic.o
diff --git a/kernel/trace/rv/reactor_panic.c b/kernel/trace/rv/reactor_panic.c
new file mode 100644
index 000000000000..9d8d78a337a3
--- /dev/null
+++ b/kernel/trace/rv/reactor_panic.c
@@ -0,0 +1,44 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Panic RV reactor:
+ *   Prints the exception msg to the kernel message log and panic().
+ *
+ * Copyright (C) 2019-2022 Daniel Bristot de Oliveira <bristot@kernel.org>
+ *
+ */
+
+#include <linux/ftrace.h>
+#include <linux/tracepoint.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/rv.h>
+
+static void rv_panic_reaction(char *msg)
+{
+	panic(msg);
+}
+
+struct rv_reactor rv_panic = {
+	.name = "panic",
+	.description = "panic the system if an exception is found.",
+	.react = rv_panic_reaction
+};
+
+int register_react_panic(void)
+{
+	rv_register_reactor(&rv_panic);
+	return 0;
+}
+
+void unregister_react_panic(void)
+{
+	rv_unregister_reactor(&rv_panic);
+}
+
+module_init(register_react_panic);
+module_exit(unregister_react_panic);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Daniel Bristot de Oliveira");
+MODULE_DESCRIPTION("panic rv reactor: panic if an exception is found");