[PATCH] samples/kprobes: Update jprobe_example.c for do_fork() change

[PATCH] samples/kprobes: Update jprobe_example.c for do_fork() change

[Michael Ellerman]

In commit e80d666 "flagday: kill pt_regs argument of do_fork()", the
arguments to do_fork() changed.

The example code in jprobe_example.c was not updated to match, so the
arguments inside the jprobe handler do not match reality.

Fix it by updating the arguments to match do_fork(). While we're at it
use pr_info() for brevity, and print stack_start as well for interest.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 samples/kprobes/jprobe_example.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/samples/kprobes/jprobe_example.c b/samples/kprobes/jprobe_example.c
index b754135..9119ac6 100644
--- a/samples/kprobes/jprobe_example.c
+++ b/samples/kprobes/jprobe_example.c
@@ -24,12 +24,11 @@
 
 /* Proxy routine having the same arguments as actual do_fork() routine */
 static long jdo_fork(unsigned long clone_flags, unsigned long stack_start,
-	      struct pt_regs *regs, unsigned long stack_size,
-	      int __user *parent_tidptr, int __user *child_tidptr)
+	      unsigned long stack_size, int __user *parent_tidptr,
+	      int __user *child_tidptr)
 {
-	printk(KERN_INFO "jprobe: clone_flags = 0x%lx, stack_size = 0x%lx,"
-			" regs = 0x%p\n",
-	       clone_flags, stack_size, regs);
+	pr_info("jprobe: clone_flags = 0x%lx, stack_start = 0x%lx "
+		"stack_size = 0x%lx\n", clone_flags, stack_start, stack_size);
 
 	/* Always end with a call to jprobe_return(). */
 	jprobe_return();
-- 
1.9.1

Re: [PATCH] samples/kprobes: Update jprobe_example.c for do_fork() change

[Masami Hiramatsu]

(2014/06/23 12:10), Michael Ellerman wrote:
> In commit e80d666 "flagday: kill pt_regs argument of do_fork()", the
> arguments to do_fork() changed.
> 
> The example code in jprobe_example.c was not updated to match, so the
> arguments inside the jprobe handler do not match reality.
> 
> Fix it by updating the arguments to match do_fork(). While we're at it
> use pr_info() for brevity, and print stack_start as well for interest.
> 
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

Thanks!

> ---
>  samples/kprobes/jprobe_example.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/samples/kprobes/jprobe_example.c b/samples/kprobes/jprobe_example.c
> index b754135..9119ac6 100644
> --- a/samples/kprobes/jprobe_example.c
> +++ b/samples/kprobes/jprobe_example.c
> @@ -24,12 +24,11 @@
>  
>  /* Proxy routine having the same arguments as actual do_fork() routine */
>  static long jdo_fork(unsigned long clone_flags, unsigned long stack_start,
> -	      struct pt_regs *regs, unsigned long stack_size,
> -	      int __user *parent_tidptr, int __user *child_tidptr)
> +	      unsigned long stack_size, int __user *parent_tidptr,
> +	      int __user *child_tidptr)
>  {
> -	printk(KERN_INFO "jprobe: clone_flags = 0x%lx, stack_size = 0x%lx,"
> -			" regs = 0x%p\n",
> -	       clone_flags, stack_size, regs);
> +	pr_info("jprobe: clone_flags = 0x%lx, stack_start = 0x%lx "
> +		"stack_size = 0x%lx\n", clone_flags, stack_start, stack_size);
>  
>  	/* Always end with a call to jprobe_return(). */
>  	jprobe_return();
> 


-- 
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Research Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com