Re: [PATCH] selftests/ftrace: update kprobe syntax error test for ppc64le

[Masami Hiramatsu (Google) <mhiramat@kernel.org>]

On Mon, 4 Nov 2024 15:02:12 +0530
Hari Bathini <hbathini@linux.ibm.com> wrote:

> 
> 
> On 03/11/24 10:27 am, Masami Hiramatsu (Google) wrote:
> > On Sat,  2 Nov 2024 00:49:25 +0530
> > Hari Bathini <hbathini@linux.ibm.com> wrote:
> > 
> >> For ppc64le, depending on the kernel configuration used, offset 16
> >> from function start address can also be considered function entry.
> >> Update the test case to accommodate such configurations.
> >>
> > 
> > Hi Hari, so have you met any error on this test case?
> 
> Hi Masami,
> 
> vfs_read+8 is function entry on powerpc. So, the test case bails out at:
>    "check_error 'p vfs_read+8 ^$arg*'		# NOFENTRY_ARGS"
> 
> as it allows setting kprobe "vfs_read+8 $arg*"
> 
> > Can you share the error result too?
> 
> 
> End of the log file for reference:
> 
> "
> Test command: p vfs_read $arg* $arg*
> [2661828.483436] trace_kprobe: error: $arg* can be used only once in the 
> parameters
>    Command: p vfs_read $arg* $arg*
>                              ^
> Test command: p vfs_read+8 $arg*
> "

Ah, OK. so it should fail but passed. (and test failure)

Thank you,

> 
> Thanks
> Hari
> 
> > 
> > Thank you,
> > 
> >> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
> >> ---
> >>   .../selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc    | 4 ++++
> >>   1 file changed, 4 insertions(+)
> >>
> >> diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
> >> index a16c6a6f6055..c03b94cc5784 100644
> >> --- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
> >> +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
> >> @@ -111,7 +111,11 @@ check_error 'p vfs_read $arg* ^$arg*'		# DOUBLE_ARGS
> >>   if !grep -q 'kernel return probes support:' README; then
> >>   check_error 'r vfs_read ^$arg*'			# NOFENTRY_ARGS
> >>   fi
> >> +if [ "$(uname -m)" = "ppc64le" ]; then
> >> +check_error 'p vfs_read+20 ^$arg*'		# NOFENTRY_ARGS
> >> +else
> >>   check_error 'p vfs_read+8 ^$arg*'		# NOFENTRY_ARGS
> >> +fi
> >>   check_error 'p vfs_read ^hoge'			# NO_BTFARG
> >>   check_error 'p kfree ^$arg10'			# NO_BTFARG (exceed the number of parameters)
> >>   check_error 'r kfree ^$retval'			# NO_RETVAL
> >> -- 
> >> 2.47.0
> >>
> > 
> > 
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>