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  1. 25 Jun, 2020 35 commits
  3. 22 Jun, 2020 5 commits
    • Greg Kroah-Hartman's avatar
      Linux 4.19.129 · b3a99fd3
      Greg Kroah-Hartman authored
      b3a99fd3
    • Adrian Hunter's avatar
      perf symbols: Fix debuginfo search for Ubuntu · 7e8c391e
      Adrian Hunter authored 
      commit 85afd355 upstream.

Reportedly, from 19.10 Ubuntu has begun mixing up the location of some
debug symbol files, putting files expected to be in
/usr/lib/debug/usr/lib into /usr/lib/debug/lib instead. Fix by adding
another dso_binary_type.

Example on Ubuntu 20.04

  Before:

    $ perf record -e intel_pt//u uname
    Linux
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.030 MB perf.data ]
    $ perf script --call-trace | head -5
           uname 14003 [005] 15321.764958566:  cbr: 42 freq: 4219 MHz (156%)
           uname 14003 [005] 15321.764958566: (/usr/lib/x86_64-linux-gnu/ld-2.31.so              )          7f1e71cc4100
           uname 14003 [005] 15321.764961566: (/usr/lib/x86_64-linux-gnu/ld-2.31.so              )              7f1e71cc4df0
           uname 14003 [005] 15321.764961900: (/usr/lib/x86_64-linux-gnu/ld-2.31.so              )              7f1e71cc4e18
           uname 14003 [005] 15321.764963233: (/usr/lib/x86_64-linux-gnu/ld-2.31.so              )              7f1e71cc5128

  After:

    $ perf script --call-trace | head -5
           uname 14003 [005] 15321.764958566:  cbr: 42 freq: 4219 MHz (156%)
           uname 14003 [005] 15321.764958566: (/usr/lib/x86_64-linux-gnu/ld-2.31.so              )      _start
           uname 14003 [005] 15321.764961566: (/usr/lib/x86_64-linux-gnu/ld-2.31.so              )          _dl_start
           uname 14003 [005] 15321.764961900: (/usr/lib/x86_64-linux-gnu/ld-2.31.so              )          _dl_start
           uname 14003 [005] 15321.764963233: (/usr/lib/x86_64-linux-gnu/ld-2.31.so              )          _dl_start
Reported-by: default avatarTravis Downs <travis.downs@gmail.com>
Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200526155207.9172-1-adrian.hunter@intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7e8c391e
    • Masami Hiramatsu's avatar
      perf probe: Check address correctness by map instead of _etext · c7006692
      Masami Hiramatsu authored 
      commit 2ae5d0d7 upstream.

Since commit 03db8b58 ("perf tools: Fix
maps__find_symbol_by_name()") introduced map address range check in
maps__find_symbol_by_name(), we can not get "_etext" from kernel map
because _etext is placed on the edge of the kernel .text section (=
kernel map in perf.)

To fix this issue, this checks the address correctness by map address
range information (map->start and map->end) instead of using _etext
address.

This can cause an error if the target inlined function is embedded in
both __init function and normal function.

For exaample, request_resource() is a normal function but also embedded
in __init reserve_setup(). In this case, the probe point in
reserve_setup() must be skipped.

However, without this fix, it failes to setup all probe points:

  # ./perf probe -v request_resource
  probe-definition(0): request_resource
  symbol:request_resource file:(null) line:0 offset:0 return:0 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /usr/lib/debug/lib/modules/5.5.17-200.fc31.x86_64/vmlinux for symbols
  Open Debuginfo file: /usr/lib/debug/lib/modules/5.5.17-200.fc31.x86_64/vmlinux
  Try to find probe point from debuginfo.
  Matched function: request_resource [15e29ad]
  found inline addr: 0xffffffff82fbf892
  Probe point found: reserve_setup+204
  found inline addr: 0xffffffff810e9790
  Probe point found: request_resource+0
  Found 2 probe_trace_events.
  Opening /sys/kernel/debug/tracing//kprobe_events write=1
  Opening /sys/kernel/debug/tracing//README write=0
  Writing event: p:probe/request_resource _text+33290386
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)
  #

With this fix,

  # ./perf probe request_resource
  reserve_setup is out of .text, skip it.
  Added new events:
    (null):(null)        (on request_resource)
    probe:request_resource (on request_resource)

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

  	perf record -e probe:request_resource -aR sleep 1

  #

Fixes: 03db8b58 ("perf tools: Fix maps__find_symbol_by_name()")
Reported-by: default avatarArnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763967332.30755.4922496724365529088.stgit@devnote2Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      c7006692
    • Masami Hiramatsu's avatar
      perf probe: Fix to check blacklist address correctly · 3a19dcd4
      Masami Hiramatsu authored 
      commit 80526491 upstream.

Fix to check kprobe blacklist address correctly with relocated address
by adjusting debuginfo address.

Since the address in the debuginfo is same as objdump, it is different
from relocated kernel address with KASLR.  Thus, 'perf probe' always
misses to catch the blacklisted addresses.

Without this patch, 'perf probe' can not detect the blacklist addresses
on a KASLR enabled kernel.

  # perf probe kprobe_dispatcher
  Failed to write event: Invalid argument
    Error: Failed to add events.
  #

With this patch, it correctly shows the error message.

  # perf probe kprobe_dispatcher
  kprobe_dispatcher is blacklisted function, skip it.
  Probe point 'kprobe_dispatcher' not found.
    Error: Failed to add events.
  #

Fixes: 9aaf5a5f ("perf probe: Check kprobes blacklist when adding new events")
Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763966411.30755.5882376357738273695.stgit@devnote2Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      3a19dcd4
    • Masami Hiramatsu's avatar
      perf probe: Do not show the skipped events · 10846d82
      Masami Hiramatsu authored 
      commit f41ebe9d upstream.

When a probe point is expanded to several places (like inlined) and if
some of them are skipped because of blacklisted or __init function,
those trace_events has no event name. It must be skipped while showing
results.

Without this fix, you can see "(null):(null)" on the list,

  # ./perf probe request_resource
  reserve_setup is out of .text, skip it.
  Added new events:
    (null):(null)        (on request_resource)
    probe:request_resource (on request_resource)

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

  	perf record -e probe:request_resource -aR sleep 1

  #

With this fix, it is ignored:

  # ./perf probe request_resource
  reserve_setup is out of .text, skip it.
  Added new events:
    probe:request_resource (on request_resource)

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

  	perf record -e probe:request_resource -aR sleep 1

  #

Fixes: 5a51fcd1 ("perf probe: Skip kernel symbols which is out of .text")
Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763968263.30755.12800484151476026340.stgit@devnote2Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      10846d82
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