linux-toradex.git/kernel/trace, branch v5.17-rc4

tracing: Fix tp_printk option related with tp_printk_stop_on_boot

2022-02-08T20:47:00+00:00

The kernel parameter "tp_printk_stop_on_boot" starts with "tp_printk" which is
the same as another kernel parameter "tp_printk". If "tp_printk" setup is
called before the "tp_printk_stop_on_boot", it will override the latter
and keep it from being set.

This is similar to other kernel parameter issues, such as:
  Commit 745a600cf1a6 ("um: console: Ignore console= option")
or init/do_mounts.c:45 (setup function of "ro" kernel param)

Fix it by checking for a "_" right after the "tp_printk" and if that
exists do not process the parameter.

Link: https://lkml.kernel.org/r/20220208195421.969326-1-jsyoo5b@gmail.com

Signed-off-by: JaeSang Yoo 
[ Fixed up change log and added space after if condition ]
Signed-off-by: Steven Rostedt (Google)

tracing: Don't inc err_log entry count if entry allocation fails

2022-01-28T00:15:49+00:00

tr->n_err_log_entries should only be increased if entry allocation
succeeds.

Doing it when it fails won't cause any problems other than wasting an
entry, but should be fixed anyway.

Link: https://lkml.kernel.org/r/cad1ab28f75968db0f466925e7cba5970cec6c29.1643319703.git.zanussi@kernel.org

Cc: stable@vger.kernel.org
Fixes: 2f754e771b1a6 ("tracing: Don't inc err_log entry count if entry allocation fails")
Signed-off-by: Tom Zanussi 
Signed-off-by: Steven Rostedt (Google)

tracing: Propagate is_signed to expression

2022-01-28T00:15:49+00:00

During expression parsing, a new expression field is created which
should inherit the properties of the operands, such as size and
is_signed.

is_signed propagation was missing, causing spurious errors with signed
operands.  Add it in parse_expr() and parse_unary() to fix the problem.

Link: https://lkml.kernel.org/r/f4dac08742fd7a0920bf80a73c6c44042f5eaa40.1643319703.git.zanussi@kernel.org

Cc: stable@vger.kernel.org
Fixes: 100719dcef447 ("tracing: Add simple expression support to hist triggers")
Reported-by: Yordan Karadzhov 
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215513
Signed-off-by: Tom Zanussi 
Signed-off-by: Steven Rostedt (Google)

tracing: Fix smatch warning for do while check in event_hist_trigger_parse()

2022-01-28T00:15:48+00:00

The patch ec5ce0987541: "tracing: Allow whitespace to surround hist
trigger filter" from Jan 15, 2018, leads to the following Smatch
static checker warning:

    kernel/trace/trace_events_hist.c:6199 event_hist_trigger_parse()
    warn: 'p' can't be NULL.

Since p is always checked for a NULL value at the top of loop and
nothing in the rest of the loop will set it to NULL, the warning
is correct and might as well be 1 to silence the warning.

Link: https://lkml.kernel.org/r/a1d4c79766c0cf61e20438dc35244d216633fef6.1643319703.git.zanussi@kernel.org

Fixes: ec5ce09875410 ("tracing: Allow whitespace to surround hist trigger filter")
Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Tom Zanussi 
Signed-off-by: Steven Rostedt (Google)

tracing: Fix smatch warning for null glob in event_hist_trigger_parse()

2022-01-28T00:15:47+00:00

The recent rename of event_hist_trigger_parse() caused smatch
re-evaluation of trace_events_hist.c and as a result an old warning
was found:

    kernel/trace/trace_events_hist.c:6174 event_hist_trigger_parse()
    error: we previously assumed 'glob' could be null (see line 6166)

glob should never be null (and apparently smatch can also figure that
out and skip the warning when using the cross-function DB (but which
can't be used with a 0day build as it takes too much time to
generate)).

Nonetheless for clarity, remove the test but add a WARN_ON() in case
the code ever changes.

Link: https://lkml.kernel.org/r/96925e5c1f116654ada7ea0613d930b1266b5e1c.1643319703.git.zanussi@kernel.org

Fixes: f404da6e1d46c ("tracing: Add 'last error' error facility for hist triggers")
Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Tom Zanussi 
Signed-off-by: Steven Rostedt (Google)

tracing/histogram: Fix a potential memory leak for kstrdup()

2022-01-28T00:15:44+00:00

kfree() is missing on an error path to free the memory allocated by
kstrdup():

  p = param = kstrdup(data->params[i], GFP_KERNEL);

So it is better to free it via kfree(p).

Link: https://lkml.kernel.org/r/tencent_C52895FD37802832A3E5B272D05008866F0A@qq.com

Cc: stable@vger.kernel.org
Fixes: d380dcde9a07c ("tracing: Fix now invalid var_ref_vals assumption in trace action")
Signed-off-by: Xiaoke Wang 
Signed-off-by: Steven Rostedt (Google)

ftrace: Have architectures opt-in for mcount build time sorting

2022-01-28T00:15:44+00:00

First S390 complained that the sorting of the mcount sections at build
time caused the kernel to crash on their architecture. Now PowerPC is
complaining about it too. And also ARM64 appears to be having issues.

It may be necessary to also update the relocation table for the values
in the mcount table. Not only do we have to sort the table, but also
update the relocations that may be applied to the items in the table.

If the system is not relocatable, then it is fine to sort, but if it is,
some architectures may have issues (although x86 does not as it shifts all
addresses the same).

Add a HAVE_BUILDTIME_MCOUNT_SORT that an architecture can set to say it is
safe to do the sorting at build time.

Also update the config to compile in build time sorting in the sorttable
code in scripts/ to depend on CONFIG_BUILDTIME_MCOUNT_SORT.

Link: https://lore.kernel.org/all/944D10DA-8200-4BA9-8D0A-3BED9AA99F82@linux.ibm.com/
Link: https://lkml.kernel.org/r/20220127153821.3bc1ac6e@gandalf.local.home

Cc: Ingo Molnar 
Cc: Andrew Morton 
Cc: Russell King 
Cc: Yinan Liu 
Cc: Ard Biesheuvel 
Cc: Kees Cook 
Reported-by: Sachin Sant 
Reviewed-by: Mark Rutland 
Tested-by: Mark Rutland  [arm64]
Tested-by: Sachin Sant 
Fixes: 72b3942a173c ("scripts: ftrace - move the sort-processing in ftrace_init")
Signed-off-by: Steven Rostedt (Google)

Merge tag 'trace-v5.17-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2022-01-23T06:07:02+00:00

Pull ftrace fix from Steven Rostedt:
 "Fix s390 breakage from sorting mcount tables.

  The latest merge of the tracing tree sorts the mcount table at build
  time. But s390 appears to do things differently (like always) and
  replaces the sorted table back to the original unsorted one. As the
  ftrace algorithm depends on it being sorted, bad things happen when it
  is not, and s390 experienced those bad things.

  Add a new config to tell the boot if the mcount table is sorted or
  not, and allow s390 to opt out of it"

* tag 'trace-v5.17-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix assuming build time sort works for s390

ftrace: Fix assuming build time sort works for s390

2022-01-23T05:10:09+00:00

To speed up the boot process, as mcount_loc needs to be sorted for ftrace
to work properly, sorting it at build time is more efficient than boot up
and can save milliseconds of time. Unfortunately, this change broke s390
as it will modify the mcount_loc location after the sorting takes place
and will put back the unsorted locations. Since the sorting is skipped at
boot up if it is believed that it was sorted at run time, ftrace can crash
as its algorithms are dependent on the list being sorted.

Add a new config BUILDTIME_MCOUNT_SORT that is set when
BUILDTIME_TABLE_SORT but not if S390 is set. Use this config to determine
if sorting should take place at boot up.

Link: https://lore.kernel.org/all/yt9dee51ctfn.fsf@linux.ibm.com/

Fixes: 72b3942a173c ("scripts: ftrace - move the sort-processing in ftrace_init")
Reported-by: Sven Schnelle 
Tested-by: Heiko Carstens 
Signed-off-by: Steven Rostedt (Google)

Merge tag 'trace-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2022-01-16T08:15:32+00:00

Pull tracing updates from Steven Rostedt:
"New:

- The Real Time Linux Analysis (RTLA) tool is added to the tools
directory.

- Can safely filter on user space pointers with: field.ustring ~
"match-string"

- eprobes can now be filtered like any other event.

- trace_marker(_raw) now uses stream_open() to allow multiple threads
to safely write to it. Note, this could possibly break existing
user space, but we will not know until we hear about it, and then
can revert the change if need be.

- New field in events to display when bottom halfs are disabled.

- Sorting of the ftrace functions are now done at compile time
instead of at bootup.

Infrastructure changes to support future efforts:

- Added __rel_loc type for trace events. Similar to __data_loc but
the offset to the dynamic data is based off of the location of the
descriptor and not the beginning of the event. Needed for user
defined events.

- Some simplification of event trigger code.

- Make synthetic events process its callback better to not hinder
other event callbacks that are registered. Needed for user defined
events.

And other small fixes and cleanups"

* tag 'trace-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (50 commits)
tracing: Add ustring operation to filtering string pointers
rtla: Add rtla timerlat hist documentation
rtla: Add rtla timerlat top documentation
rtla: Add rtla timerlat documentation
rtla: Add rtla osnoise hist documentation
rtla: Add rtla osnoise top documentation
rtla: Add rtla osnoise man page
rtla: Add Documentation
rtla/timerlat: Add timerlat hist mode
rtla: Add timerlat tool and timelart top mode
rtla/osnoise: Add the hist mode
rtla/osnoise: Add osnoise top mode
rtla: Add osnoise tool
rtla: Helper functions for rtla
rtla: Real-Time Linux Analysis tool
tracing/osnoise: Properly unhook events if start_per_cpu_kthreads() fails
tracing: Remove duplicate warnings when calling trace_create_file()
tracing/kprobes: 'nmissed' not showed correctly for kretprobe
tracing: Add test for user space strings when filtering on string pointers
tracing: Have syscall trace events use trace_event_buffer_lock_reserve()
...