Files
odroid-linux/include/linux
Naveen N. Rao 1d585e7090 trace/kprobes: Fix check for kretprobe offset within function entry
perf specifies an offset from _text and since this offset is fed
directly into the arch-specific helper, kprobes tracer rejects
installation of kretprobes through perf. Fix this by looking up the
actual offset from a function for the specified sym+offset.

Refactor and reuse existing routines to limit code duplication -- we
repurpose kprobe_addr() for determining final kprobe address and we
split out the function entry offset determination into a separate
generic helper.

Before patch:

  naveen@ubuntu:~/linux/tools/perf$ sudo ./perf probe -v do_open%return
  probe-definition(0): do_open%return
  symbol:do_open file:(null) line:0 offset:0 return:1 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /boot/vmlinux for symbols
  Open Debuginfo file: /boot/vmlinux
  Try to find probe point from debuginfo.
  Matched function: do_open [2d0c7ff]
  Probe point found: do_open+0
  Matched function: do_open [35d76dc]
  found inline addr: 0xc0000000004ba9c4
  Failed to find "do_open%return",
   because do_open is an inlined function and has no return point.
  An error occurred in debuginfo analysis (-22).
  Trying to use symbols.
  Opening /sys/kernel/debug/tracing//README write=0
  Opening /sys/kernel/debug/tracing//kprobe_events write=1
  Writing event: r:probe/do_open _text+4469776
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)
  naveen@ubuntu:~/linux/tools/perf$ dmesg | tail
  <snip>
  [   33.568656] Given offset is not valid for return probe.

After patch:

  naveen@ubuntu:~/linux/tools/perf$ sudo ./perf probe -v do_open%return
  probe-definition(0): do_open%return
  symbol:do_open file:(null) line:0 offset:0 return:1 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /boot/vmlinux for symbols
  Open Debuginfo file: /boot/vmlinux
  Try to find probe point from debuginfo.
  Matched function: do_open [2d0c7d6]
  Probe point found: do_open+0
  Matched function: do_open [35d76b3]
  found inline addr: 0xc0000000004ba9e4
  Failed to find "do_open%return",
   because do_open is an inlined function and has no return point.
  An error occurred in debuginfo analysis (-22).
  Trying to use symbols.
  Opening /sys/kernel/debug/tracing//README write=0
  Opening /sys/kernel/debug/tracing//kprobe_events write=1
  Writing event: r:probe/do_open _text+4469808
  Writing event: r:probe/do_open_1 _text+4956344
  Added new events:
    probe:do_open        (on do_open%return)
    probe:do_open_1      (on do_open%return)

  You can now use it in all perf tools, such as:

	  perf record -e probe:do_open_1 -aR sleep 1

  naveen@ubuntu:~/linux/tools/perf$ sudo cat /sys/kernel/debug/kprobes/list
  c000000000041370  k  kretprobe_trampoline+0x0    [OPTIMIZED]
  c0000000004ba0b8  r  do_open+0x8    [DISABLED]
  c000000000443430  r  do_open+0x0    [DISABLED]

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/d8cd1ef420ec22e3643ac332fdabcffc77319a42.1488961018.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-15 17:48:37 -03:00
..
2017-02-24 19:04:57 +01:00
2017-01-24 12:37:43 -08:00
2017-03-01 09:50:58 -08:00
2016-07-08 16:23:11 +02:00
2016-12-22 22:58:37 -05:00
2016-10-19 14:34:36 -04:00
2017-02-10 15:52:24 -05:00
2017-03-02 08:56:04 -07:00
2017-01-25 13:17:47 -05:00
2016-12-08 13:31:11 -05:00
2016-08-11 09:41:35 -06:00
2016-10-25 11:08:28 +08:00
2016-12-27 14:52:47 -05:00
2016-12-08 16:37:33 -08:00
2017-02-24 17:46:55 -08:00
2017-02-04 00:47:59 +01:00
2016-12-05 19:01:16 -05:00
2016-10-28 08:48:16 -06:00
2016-05-17 15:48:12 -04:00
2017-02-27 10:07:47 -08:00
2016-12-05 19:01:16 -05:00
2016-12-25 17:21:22 +01:00
2017-02-11 20:59:41 -05:00
2016-02-11 09:59:22 -05:00
2016-09-14 09:18:09 -06:00
2017-01-05 15:01:55 -06:00
2016-05-11 22:37:54 +02:00
2016-01-28 14:19:12 -08:00
2017-02-01 09:13:45 +01:00
2016-03-22 15:36:02 -07:00
2016-03-22 15:36:02 -07:00
2016-12-12 18:55:06 -08:00
2016-12-25 17:21:23 +01:00
2016-01-15 17:56:32 -08:00
2017-02-24 17:46:57 -08:00
2016-09-27 12:33:47 +02:00
2016-12-06 11:05:46 +01:00
2017-01-12 16:48:26 -05:00
2016-07-29 12:17:52 -07:00
2016-08-28 23:32:41 -04:00
2017-03-01 09:50:58 -08:00
2016-11-16 18:32:02 -05:00
2016-04-25 15:09:11 -04:00
2016-02-16 13:04:58 -05:00
2016-12-12 18:55:07 -08:00
2016-12-06 10:17:03 +02:00
2017-03-02 08:56:04 -07:00
2016-02-11 18:35:48 -08:00
2016-03-14 15:43:11 -04:00
2017-02-20 10:15:11 -05:00
2016-10-31 16:18:30 -04:00
2016-10-14 11:36:59 -07:00
2016-07-12 19:25:38 -07:00
2016-09-27 21:52:00 -04:00
2016-11-15 16:34:27 -08:00
2016-03-17 15:09:34 -07:00
2017-02-13 21:44:09 -05:00
2016-07-06 10:51:14 +01:00
2016-03-22 15:36:02 -07:00
2016-06-14 10:54:40 -07:00
2017-02-27 18:43:46 -08:00
2016-01-04 16:11:11 -05:00
2017-01-09 16:07:38 -05:00
2016-10-05 18:23:36 -04:00
2017-02-03 11:19:34 -05:00
2016-12-25 17:21:22 +01:00
2017-01-10 18:31:55 -08:00
2016-07-19 17:43:38 +03:00
2017-02-03 10:17:02 +01:00
2016-12-09 22:12:21 -05:00
2017-02-10 16:34:17 +00:00
2016-12-12 18:55:08 -08:00
2017-01-11 09:21:41 +01:00
2015-12-03 07:24:29 -08:00
2017-02-02 15:22:18 -05:00