bootconfig: Rename xbc_node_find_child() to xbc_node_find_subkey()
Rename xbc_node_find_child() to xbc_node_find_subkey() for
clarifying that function returns a key node (no value node).
Since there are xbc_node_for_each_child() (loop on all child
nodes) and xbc_node_for_each_subkey() (loop on only subkey
nodes), this name distinction is necessary to avoid confusing
users.
tracing/boot: Fix to check the histogram control param is a leaf node
Since xbc_node_find_child() doesn't ensure the returned node
is a leaf node (key-value pair or do not have subkeys),
use xbc_node_find_value to ensure the histogram control
parameter is a leaf node in trace_boot_compose_hist_cmd().
tracing/boot: Fix trace_boot_hist_add_array() to check array is value
trace_boot_hist_add_array() uses the combination of
xbc_node_find_child() and xbc_node_get_child() to get the
child node of the key node. But since it missed to check
the child node is data node or not, user can pass the
subkey node for the array node (anode).
To avoid this issue, check the array node is a data node.
Actually, there is xbc_node_find_value(node, key, vnode),
which ensures the @vnode is a value node, so use it in
trace_boot_hist_add_array() to fix this issue.
Since the commit e5efaeb8a8f5 ("bootconfig: Support mixing
a value and subkeys under a key") allows to co-exist a value
node and key nodes under a node, xbc_node_for_each_child()
is not only returning key node but also a value node.
In the boot-time tracing using xbc_node_for_each_child() to
iterate the events, groups and instances, but those must be
key nodes. Thus it must use xbc_node_for_each_subkey().
selftests/ftrace: Exclude "(fault)" in testing add/remove eprobe events
The original test for adding and removing eprobes used synthetic events
and retrieved the filename from the open system call at the end of the
system call. This would allow it to always be loaded into the page tables
when accessed.
Masami suggested that the test was too complex for just testing add and
remove, so it was changed to test just adding and removing an event probe
on top of the start of the open system call event. Now it is possible that
the filename will not be loaded into memory at the time the eprobe is
triggered, and will result in "(fault)" being displayed in the event. This
causes the test to fail.
Account for "(fault)" also being one of the values of the filename field
of the event probe.
Link: https://lkml.kernel.org/r/20210907230429.5783d519@rorschach.local.home Fixes: 079db70794ec5 ("selftests/ftrace: Add test case to test adding and removing of event probe") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tom Zanussi [Thu, 2 Sep 2021 20:57:12 +0000 (15:57 -0500)]
tracing: Dynamically allocate the per-elt hist_elt_data array
Setting the hist_elt_data.field_var_str[] array unconditionally to a
size of SYNTH_FIELD_MAX elements wastes space unnecessarily. The
actual number of elements needed can be calculated at run-time
instead.
In most cases, this will save a lot of space since it's a per-elt
array which isn't normally close to being full. It also allows us to
increase SYNTH_FIELD_MAX without worrying about even more wastage when
we do that.
Sometimes it is useful to construct larger synthetic trace events. Increase
'SYNTH_FIELDS_MAX' (maximum number of fields in a synthetic event) from 32 to
64.
Julio Faracco [Sat, 4 Sep 2021 15:54:38 +0000 (00:54 +0900)]
bootconfig: Fix missing return check of xbc_node_compose_key function
The function `xbc_show_list should` handle the keys during the
composition. Even the errors returned by the compose function. Instead
of removing the `ret` variable, it should save the value and show the
exact error. This missing variable is causing a compilation issue also.
Link: https://lkml.kernel.org/r/163077087861.222577.12884543474750968146.stgit@devnote2 Fixes: e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key") Signed-off-by: Julio Faracco <jcfaracco@gmail.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
docs: bootconfig: Add how to use bootconfig for kernel parameters
Add a section to describe how to use the bootconfig for
specifying kernel and init parameters. This is an important
section because it is the reason why this document is under
the admin-guide.
Dan Carpenter [Tue, 24 Aug 2021 11:51:50 +0000 (14:51 +0300)]
tracing: Fix some alloc_event_probe() error handling bugs
There are two bugs in this code. First, if the kzalloc() fails it leads
to a NULL dereference of "ep" on the next line. Second, if the
alloc_event_probe() function returns an error then it leads to an
error pointer dereference in the caller.
Link: https://lkml.kernel.org/r/20210824115150.GI31143@kili Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Thomas Gleixner [Tue, 10 Aug 2021 13:26:25 +0000 (15:26 +0200)]
tracing: Add migrate-disabled counter to tracing output.
migrate_disable() forbids task migration to another CPU. It is available
since v5.11 and has already users such as highmem or BPF. It is useful
to observe this task state in tracing which already has other states
like the preemption counter.
Instead of adding the migrate disable counter as a new entry to struct
trace_entry, which would extend the whole struct by four bytes, it is
squashed into the preempt-disable counter. The lower four bits represent
the preemption counter, the upper four bits represent the migrate
disable counter. Both counter shouldn't exceed 15 but if they do, there
is a safety net which caps the value at 15.
Add the migrate-disable counter to the trace entry so it shows up in the
trace. Due to the users mentioned above, it is already possible to
observe it:
Things that popped up:
- trace_print_lat_context() does not print the migrate counter. Not sure
if it should. It is used in "verbose" mode and uses 8 digits and I'm
not sure ther is something processing the value.
- trace_define_common_fields() now defines a different variable. This
probably breaks things. No ide what to do in order to preserve the old
behaviour. Since this is used as a filter it should be split somehow
to be able to match both nibbles here.
Link: https://lkml.kernel.org/r/20210810132625.ylssabmsrkygokuv@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: patch description.] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[ SDR: Removed change to common_preempt_count field name ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The addition of the buckets conversion for the histogram code, updated the
documentation table of available conversions, but did not update the format
to accommodate the extra size needed to cover the description.
selftests/ftrace: Add selftest for testing eprobe events on synthetic events
Add a test to test event probes, by creating a synthetic event across
sys_enter_openat and sys_exit_openat that passes the filename pointer from
the enter of the system call to the exit, and then add an event probe to
the synthetic event to make sure that the file name is seen.
selftests/ftrace: Fix requirement check of README file
The selftest for ftrace checks some features by checking if the README has
text that states the feature is supported by that kernel. Unfortunately,
this check gives false positives because it many not be checked if there's
spaces in the string to check. This is due to the compare between the
required variable with the ":README" string stripped, because neither has
quotes around them.
Link: https://lkml.kernel.org/r/20210820204742.087177341@goodmis.org Cc: "Tzvetomir Stoyanov" <tz.stoyanov@gmail.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: linux-kselftest@vger.kernel.org Cc: stable@vger.kernel.org Fixes: 1b8eec510ba64 ("selftests/ftrace: Support ":README" suffix for requires") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
selftests/ftrace: Add clear_dynamic_events() to test cases
Add a function to remove all dynamic events from the tracing directory. It
requires a loop as some of the dynamic events may depend on others being
removed first. Also add a safety that prevents it from looping infinitely
due to a bug where an event never gets removed.
tracing: Add a probe that attaches to trace events
A new dynamic event is introduced: event probe. The event is attached
to an existing tracepoint and uses its fields as arguments. The user
can specify custom format string of the new event, select what tracepoint
arguments will be printed and how to print them.
An event probe is created by writing configuration string in
'dynamic_events' ftrace file:
e[:[SNAME/]ENAME] SYSTEM/EVENT [FETCHARGS] - Set an event probe
-:SNAME/ENAME - Delete an event probe
Where:
SNAME - System name, if omitted 'eprobes' is used.
ENAME - Name of the new event in SNAME, if omitted the SYSTEM_EVENT is used.
SYSTEM - Name of the system, where the tracepoint is defined, mandatory.
EVENT - Name of the tracepoint event in SYSTEM, mandatory.
FETCHARGS - Arguments:
<name>=$<field>[:TYPE] - Fetch given filed of the tracepoint and print
it as given TYPE with given name. Supported
types are:
(u8/u16/u32/u64/s8/s16/s32/s64), basic type
(x8/x16/x32/x64), hexadecimal types
"string", "ustring" and bitfield.
Example, attach an event probe on openat system call and print name of the
file that will be opened:
echo "e:esys/eopen syscalls/sys_enter_openat file=\$filename:string" >> dynamic_events
A new dynamic event is created in events/esys/eopen/ directory. It
can be deleted with:
echo "-:esys/eopen" >> dynamic_events
Filters, triggers and histograms can be attached to the new event, it can
be matched in synthetic events. There is one limitation - an event probe
can not be attached to kprobe, uprobe or another event probe.
Masami Hiramatsu [Thu, 19 Aug 2021 10:26:02 +0000 (19:26 +0900)]
tracing/probes: Reject events which have the same name of existing one
Since kprobe_events and uprobe_events only check whether the
other same-type probe event has the same name or not, if the
user gives the same name of the existing tracepoint event (or
the other type of probe events), it silently fails to create
the tracefs entry (but registered.) as below.
/sys/kernel/tracing # ls events/task/task_rename
enable filter format hist id trigger
/sys/kernel/tracing # echo p:task/task_rename vfs_read >> kprobe_events
[ 113.048508] Could not create tracefs 'task_rename' directory
/sys/kernel/tracing # cat kprobe_events
p:task/task_rename vfs_read
To fix this issue, check whether the existing events have the
same name or not in trace_probe_register_event_call(). If exists,
it rejects to register the new event.
tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs
In preparation to allow event probes to use the process_fetch_insn()
callback in trace_probe_tmpl.h, change the data passed to it from a
pointer to pt_regs, as the event probe will not be using regs, and make it
a void pointer instead.
Update the process_fetch_insn() callers for kprobe and uprobe events to
have the regs defined in the function and just typecast the void pointer
parameter.
tracing/probe: Change traceprobe_set_print_fmt() to take a type
Instead of a boolean "is_return" have traceprobe_set_print_fmt() take a
type (currently just PROBE_PRINT_NORMAL and PROBE_PRINT_RETURN). This will
simplify adding different types. For example, the development of the
event_probe, will need its own type as it prints an event, and not an IP.
tracing/probes: Use struct_size() instead of defining custom macros
Remove SIZEOF_TRACE_KPROBE() and SIZEOF_TRACE_UPROBE() and use
struct_size() as that's what it is made for. No need to have custom
macros. Especially since struct_size() has some extra memory checks for
correctness.
tracing/probes: Allow for dot delimiter as well as slash for system names
Kprobe and uprobe events can add a "system" to the events that are created
via the kprobe_events and uprobe_events files respectively. If they do not
include a "system" in the name, then the default "kprobes" or "uprobes" is
used. The current notation to specify a system for one of these probe
events is to add a '/' delimiter in the name, where the content before the
'/' will be the system to use, and the content after will be the event
name.
echo 'p:my_system/my_event' > kprobe_events
But this is inconsistent with the way histogram triggers separate their
system / event names. The histogram triggers use a '.' delimiter, which
can be confusing.
To allow this to be more consistent, as well as keep backward
compatibility, allow the kprobe and uprobe events to denote a system name
with either a '/' or a '.'.
tracing/probe: Have traceprobe_parse_probe_arg() take a const arg
The two places that call traceprobe_parse_probe_arg() allocate a temporary
buffer to copy the argv[i] into, because argv[i] is constant and the
traceprobe_parse_probe_arg() will modify it to do the parsing. These two
places allocate this buffer and then free it right after calling this
function, leaving the onus of this allocation to the caller.
As there's about to be a third user of this function that will have to do
the same thing, instead of having the caller allocate the temporary
buffer, simply move that allocation into the traceprobe_parse_probe_arg()
itself, which will simplify the code of the callers.
As dynamic events are not created by modules, if something is attached to
one, calling "try_module_get()" on its "mod" field, is not going to keep
the dynamic event from going away.
Since dynamic events do not need the "mod" pointer of the event structure,
make a union out of it in order to save memory (there's one structure for
each of the thousand+ events in the kernel), and have any event with the
DYNAMIC flag set to use a ref counter instead.
To differentiate between static and dynamic events, add a new flag
DYNAMIC to the event flags that all dynamic events have set. This will
allow to differentiate when attaching to a dynamic event from a static
event.
Static events have a mod pointer that references the module they were
created in (or NULL for core kernel). This can be incremented when the
event has something attached to it. But there exists no such mechanism for
dynamic events. This is dangerous as the dynamic events may now disappear
without the "attachment" knowing that it no longer exists.
To enforce the dynamic flag, change dyn_event_add() to pass the event that
is being created such that it can set the DYNAMIC flag of the event. This
helps make sure that no location that creates a dynamic event misses
setting this flag.
The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().
Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.
Link: https://lkml.kernel.org/r/20210803141621.780504-37-bigeasy@linutronix.de Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The "latency" tracers have some different requirements than normal
tracing, and also includes Daniel as a maintainer. Add a section in the
MAINTAINERS file to help direct patches and bug reports to these tracers
to the right people.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
zhaoxiao [Mon, 16 Aug 2021 05:24:30 +0000 (13:24 +0800)]
tracepoint: Fix kerneldoc comments
Fix function name in tracepoint.c kernel-doc comment
to remove a warning found by clang_w1.
kernel/tracepoint.c:589: warning: expecting prototype for register_tracepoint_notifier(). Prototype was for register_tracepoint_module_notifier() instead
kernel/tracepoint.c:613: warning: expecting prototype for unregister_tracepoint_notifier(). Prototype was for unregister_tracepoint_module_notifier() instead
Masami Hiramatsu [Tue, 10 Aug 2021 02:08:22 +0000 (11:08 +0900)]
bootconfig/tracing/ktest: Update ktest example for boot-time tracing
Update ktest example for the boot-time tracing with histogram
options. Note that since the histogram option uses "trace()" action
instead of "EVENT()", this updates the matching pattern too.
Masami Hiramatsu [Tue, 10 Aug 2021 02:07:44 +0000 (11:07 +0900)]
tracing/boot: Show correct histogram error command
Since trigger_process_regex() modifies given trigger actions
while parsing, the error message couldn't show what command
was passed to the trigger_process_regex() when it returns
an error.
To fix that, show the backed up trigger action command
instead of parsed buffer.
Masami Hiramatsu [Tue, 10 Aug 2021 02:07:29 +0000 (11:07 +0900)]
tracing/boot: Support multiple handlers for per-event histogram
Support multiple handlers for per-event histogram in boot-time tracing.
Since the histogram can register multiple same handler-actions with
different parameters, this expands the syntax to support such cases.
With this update, the 'onmax', 'onchange' and 'onmatch' handler subkeys
under per-event histogram option will take a number subkeys optionally
as below. (see [.N])
Then, it can trace the elapsed time from GROUP1.STARTEVENT1 to
SOMEGROUP.SOMEEVENT, and from GROUP2.STARTEVENT2 to
SOMEGROUP.SOMEEVENT with SOME_ID key.
Add a hist-trigger action syntax support to boot-time tracing.
Currently, boot-time tracing supports per-event actions as option
strings. However, for the histogram action, it has a special syntax
and usually needs a long action definition.
To make it readable and fit to the bootconfig syntax, this introduces
a new options for histogram.
Here are the histogram action options for boot-time tracing.
tracing: Allow execnames to be passed as args for synthetic events
Allow common_pid.execname to be saved in a variable in one histogram to be
passed to another histogram that can pass it as a parameter to a synthetic
event.
The above is a wake up latency synthetic event setup that passes the execname
of the common_pid that woke the task to the scheduling of that task, which
triggers a synthetic event that passes the original execname as a
parameter to display it.
tracing: Have histogram types be constant when possible
Instead of kstrdup("const", GFP_KERNEL), have the hist_field type simply
assign the constant hist_field->type = "const"; And when the value passed
to it is a variable, use "kstrdup_const(var, GFP_KERNEL);" which will just
copy the value if the variable is already a constant. This saves on having
to allocate when not needed.
All frees of the hist_field->type will need to use kfree_const().
tracing/histogram: Update the documentation for the buckets modifier
Update both the tracefs README file as well as the histogram.rst to
include an explanation of what the buckets modifier is and how to use it.
Include an example with the wakeup_latency example for both log2 and the
buckets modifiers as there was no existing log2 example.
There's been several times I wished the histogram logic had a "grouping"
feature for the buckets. Currently, each bucket has a size of one. That
is, if you trace the amount of requested allocations, each allocation is
its own bucket, even if you are interested in what allocates 100 bytes or
less, 100 to 200, 200 to 300, etc.
Also, without grouping, it fills up the allocated histogram buckets
quickly. If you are tracking latency, and don't care if something is 200
microseconds off, or 201 microseconds off, but want to track them by say
10 microseconds each. This can not currently be done.
There is a log2 but that grouping get's too big too fast for a lot of
cases.
Introduce a "buckets=SIZE" command to each field where it will record in a
rounded number. For example:
Link: https://lkml.kernel.org/r/20210707213921.980359719@goodmis.org Acked-by: Namhyung Kim <namhyung@kernel.org> Reviewed-by: Tom Zanussi <zanussi@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Masami Hiramatsu [Tue, 10 Aug 2021 02:07:14 +0000 (11:07 +0900)]
tracing/boot: Fix a hist trigger dependency for boot time tracing
Fixes a build error when CONFIG_HIST_TRIGGERS=n with boot-time
tracing. Since the trigger_process_regex() is defined only
when CONFIG_HIST_TRIGGERS=y, if it is disabled, the 'actions'
event option also must be disabled.
Pingfan Liu [Sat, 14 Aug 2021 03:45:38 +0000 (11:45 +0800)]
tracing: Apply trace filters on all output channels
The event filters are not applied on all of the output, which results in
the flood of printk when using tp_printk. Unfolding
event_trigger_unlock_commit_regs() into trace_event_buffer_commit(), so
the filters can be applied on every output.
Link: https://lkml.kernel.org/r/20210814034538.8428-1-kernelfans@gmail.com Cc: stable@vger.kernel.org Fixes: 0daa2302968c1 ("tracing: Add tp_printk cmdline to have tracepoints go to printk()") Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The problem was the "trace(read_max,count)" where the "count" should be
"$count" as "onmax()" only handles variables (although it really should be
able to figure out that "count" is a field of sys_enter_read). But there's
a path that does not find the variable and ends up passing a NULL for the
event, which ends up getting passed to "strcmp()".
Add a check for NULL to return and error on the command with:
# cat error_log
hist:syscalls:sys_enter_read: error: Couldn't create or find variable
Command: hist:keys=common_pid:count=count:onmax($count).trace(read_max,count)
^ Link: https://lkml.kernel.org/r/20210808003011.4037f8d0@oasis.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: stable@vger.kernel.org Fixes: 50450603ec9cb tracing: Add 'onmax' hist trigger action support Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
init: Suppress wrong warning for bootconfig cmdline parameter
Since the 'bootconfig' command line parameter is handled before
parsing the command line, it doesn't use early_param(). But in
this case, kernel shows a wrong warning message about it.
Commit 2860cd8a2353 ("livepatch: Use the default ftrace_ops instead of
REGS when ARGS is available") intends to enable config LIVEPATCH when
ftrace with ARGS is available. However, the chain of configs to enable
LIVEPATCH is incomplete, as HAVE_DYNAMIC_FTRACE_WITH_ARGS is available,
but the definition of DYNAMIC_FTRACE_WITH_ARGS, combining DYNAMIC_FTRACE
and HAVE_DYNAMIC_FTRACE_WITH_ARGS, needed to enable LIVEPATCH, is missing
in the commit.
Fortunately, ./scripts/checkkconfigsymbols.py detects this and warns:
So, define the config DYNAMIC_FTRACE_WITH_ARGS analogously to the already
existing similar configs, DYNAMIC_FTRACE_WITH_REGS and
DYNAMIC_FTRACE_WITH_DIRECT_CALLS, in ./kernel/trace/Kconfig to connect the
chain of configs.
trace/timerlat: Add a header with PREEMPT_RT additional fields
Some extra flags are printed to the trace header when using the
PREEMPT_RT config. The extra flags are: need-resched-lazy,
preempt-lazy-depth, and migrate-disable.
Without printing these fields, the timerlat specific fields are
shifted by three positions, for example:
trace/osnoise: Add a header with PREEMPT_RT additional fields
Some extra flags are printed to the trace header when using the
PREEMPT_RT config. The extra flags are: need-resched-lazy,
preempt-lazy-depth, and migrate-disable.
Without printing these fields, the osnoise specific fields are
shifted by three positions, for example:
tracepoint: Use rcu get state and cond sync for static call updates
State transitions from 1->0->1 and N->2->1 callbacks require RCU
synchronization. Rather than performing the RCU synchronization every
time the state change occurs, which is quite slow when many tracepoints
are registered in batch, instead keep a snapshot of the RCU state on the
most recent transitions which belong to a chain, and conditionally wait
for a grace period on the last transition of the chain if one g.p. has
not elapsed since the last snapshot.
This applies to both RCU and SRCU.
This brings the performance regression caused by commit 231264d6927f
("Fix: tracepoint: static call function vs data state mismatch") back to
what it was originally.
Before this commit:
# trace-cmd start -e all
# time trace-cmd start -p nop
real 0m10.593s
user 0m0.017s
sys 0m0.259s
After this commit:
# trace-cmd start -e all
# time trace-cmd start -p nop
real 0m0.878s
user 0m0.000s
sys 0m0.103s
Link: https://lkml.kernel.org/r/20210805192954.30688-1-mathieu.desnoyers@efficios.com Link: https://lore.kernel.org/io-uring/4ebea8f0-58c9-e571-fd30-0ce4f6f09c70@samba.org/ Cc: stable@vger.kernel.org Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Stefan Metzmacher <metze@samba.org> Fixes: 231264d6927f ("Fix: tracepoint: static call function vs data state mismatch") Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
----> [ delayed here on one CPU (e.g. vcpu preempted by the host) ]
static_call(tp_func_##name)(__data, args); \
} \
} while (0)
It has loaded the tp->funcs of the old callback, so it will try to use the old
data. This can be fixed by adding a RCU sync anywhere in the 1->0->1
transition chain.
On a N->2->1 transition, we need an rcu-sync because you may have a
sequence of 3->2->1 (or 1->2->1) where the element 0 data is unchanged
between 2->1, but was changed from 3->2 (or from 1->2), which may be
observed by the static call. This can be fixed by adding an
unconditional RCU sync in transition 2->1.
Note, this fixes a correctness issue at the cost of adding a tremendous
performance regression to the disabling of tracepoints.
Before this commit:
# trace-cmd start -e all
# time trace-cmd start -p nop
real 0m0.778s
user 0m0.000s
sys 0m0.061s
After this commit:
# trace-cmd start -e all
# time trace-cmd start -p nop
real 0m10.593s
user 0m0.017s
sys 0m0.259s
A follow up fix will introduce a more lightweight scheme based on RCU
get_state and cond_sync, that will return the performance back to what it
was. As both this change and the lightweight versions are complex on their
own, for bisecting any issues that this may cause, they are kept as two
separate changes.
tracepoint: static call: Compare data on transition from 2->1 callees
On transition from 2->1 callees, we should be comparing .data rather
than .func, because the same callback can be registered twice with
different data, and what we care about here is that the data of array
element 0 is unchanged to skip rcu sync.
tracing: Quiet smp_processor_id() use in preemptable warning in hwlat
The hardware latency detector (hwlat) has a mode that it runs one thread
across CPUs. The logic to move from the currently running CPU to the next
one in the list does a smp_processor_id() to find where it currently is.
Unfortunately, it's done with preemption enabled, and this triggers a
warning for using smp_processor_id() in a preempt enabled section.
As it is only using smp_processor_id() to get information on where it
currently is in order to simply move it to the next CPU, it doesn't really
care if it got moved in the mean time. It will simply balance out later if
such a case arises.
Switch smp_processor_id() to raw_smp_processor_id() to quiet that warning.
Hui Su [Fri, 11 Jun 2021 02:21:07 +0000 (10:21 +0800)]
scripts/tracing: fix the bug that can't parse raw_trace_func
Since commit 77271ce4b2c0 ("tracing: Add irq, preempt-count and need resched info
to default trace output"), the default trace output format has been changed to:
<idle>-0 [009] d.h. 22420.068695: _raw_spin_lock_irqsave <-hrtimer_interrupt
<idle>-0 [000] ..s. 22420.068695: _nohz_idle_balance <-run_rebalance_domains
<idle>-0 [011] d.h. 22420.068695: account_process_tick <-update_process_times
The draw_functrace.py(introduced in v2.6.28) can't parse the new version format trace_func,
So we need modify draw_functrace.py to adapt the new version trace output format.
Link: https://lkml.kernel.org/r/20210611022107.608787-1-suhui@zeku.com Cc: stable@vger.kernel.org Fixes: 77271ce4b2c0 tracing: Add irq, preempt-count and need resched info to default trace output Signed-off-by: Hui Su <suhui@zeku.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
scripts/recordmcount.pl: Remove check_objcopy() and $can_use_local
When building ARCH=riscv allmodconfig with llvm-objcopy, the objcopy
version warning from this script appears:
WARNING: could not find objcopy version or version is less than 2.17.
Local function references are disabled.
The check_objcopy() function in scripts/recordmcount.pl is set up to
parse GNU objcopy's version string, not llvm-objcopy's, which triggers
the warning.
Commit 799c43415442 ("kbuild: thin archives make default for all archs")
made binutils 2.20 mandatory and commit ba64beb17493 ("kbuild: check the
minimum assembler version in Kconfig") enforces this at configuration
time so just remove check_objcopy() and $can_use_local instead, assuming
--globalize-symbol is always available.
llvm-objcopy has supported --globalize-symbol since LLVM 7.0.0 in 2018
and the minimum version for building the kernel with LLVM is 10.0.1 so
there is no issue introduced:
tracing: Reject string operand in the histogram expression
Since the string type can not be the target of the addition / subtraction
operation, it must be rejected. Without this fix, the string type silently
converted to digits.
tracing / histogram: Give calculation hist_fields a size
When working on my user space applications, I found a bug in the synthetic
event code where the automated synthetic event field was not matching the
event field calculation it was attached to. Looking deeper into it, it was
because the calculation hist_field was not given a size.
The synthetic event fields are matched to their hist_fields either by
having the field have an identical string type, or if that does not match,
then the size and signed values are used to match the fields.
The problem arose when I tried to match a calculation where the fields
were "unsigned int". My tool created a synthetic event of type "u32". But
it failed to match. The string was:
Adding debugging into the kernel, I found that the size of "diff" was 0.
And since it was given "unsigned int" as a type, the histogram fallback
code used size and signed. The signed matched, but the size of u32 (4) did
not match zero, and the event failed to be created.
This can be worse if the field you want to match is not one of the
acceptable fields for a synthetic event. As event fields can have any type
that is supported in Linux, this can cause an issue. For example, if a
type is an enum. Then there's no way to use that with any calculations.
Have the calculation field simply take on the size of what it is
calculating.
Link: https://lkml.kernel.org/r/20210730171951.59c7743f@oasis.local.home Cc: Tom Zanussi <zanussi@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Fixes: 100719dcef447 ("tracing: Add simple expression support to hist triggers") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Kamal Agrawal [Fri, 30 Jul 2021 13:23:06 +0000 (18:53 +0530)]
tracing: Fix NULL pointer dereference in start_creating
The event_trace_add_tracer() can fail. In this case, it leads to a crash
in start_creating with below call stack. Handle the error scenario
properly in trace_array_create_dir.
tracepoints: Update static_call before tp_funcs when adding a tracepoint
Because of the significant overhead that retpolines pose on indirect
calls, the tracepoint code was updated to use the new "static_calls" that
can modify the running code to directly call a function instead of using
an indirect caller, and this function can be changed at runtime.
In the tracepoint code that calls all the registered callbacks that are
attached to a tracepoint, the following is done:
If there's just a single callback, the static_call is updated to just call
that callback directly. Once another handler is added, then the static
caller is updated to call the iterator, that simply loops over all the
funcs in the array and calls each of the callbacks like the old method
using indirect calling.
The issue was discovered with a race between updating the funcs array and
updating the static_call. The funcs array was updated first and then the
static_call was updated. This is not an issue as long as the first element
in the old array is the same as the first element in the new array. But
that assumption is incorrect, because callbacks also have a priority
field, and if there's a callback added that has a higher priority than the
callback on the old array, then it will become the first callback in the
new array. This means that it is possible to call the old callback with
the new callback data element, which can cause a kernel panic.
static_call = callback1()
funcs[] = {callback1,data1};
callback2 has higher priority than callback1
CPU 1 CPU 2
----- -----
new_funcs = {callback2,data2},
{callback1,data1}
rcu_assign_pointer(tp->funcs, new_funcs);
/*
* Now tp->funcs has the new array
* but the static_call still calls callback1
*/
/* Now callback1 is called with
* callback2's data */
[ KERNEL PANIC ]
update_static_call(iterator);
To prevent this from happening, always switch the static_call to the
iterator before assigning the tp->funcs to the new array. The iterator will
always properly match the callback with its data.
To trigger this bug:
In one terminal:
while :; do hackbench 50; done
In another terminal
echo 1 > /sys/kernel/tracing/events/sched/sched_waking/enable
while :; do
echo 1 > /sys/kernel/tracing/set_event_pid;
sleep 0.5
echo 0 > /sys/kernel/tracing/set_event_pid;
sleep 0.5
done
And it doesn't take long to crash. This is because the set_event_pid adds
a callback to the sched_waking tracepoint with a high priority, which will
be called before the sched_waking trace event callback is called.
Note, the removal to a single callback updates the array first, before
changing the static_call to single callback, which is the proper order as
the first element in the array is the same as what the static_call is
being changed to.
Link: https://lore.kernel.org/io-uring/4ebea8f0-58c9-e571-fd30-0ce4f6f09c70@samba.org/ Cc: stable@vger.kernel.org Fixes: d25e37d89dd2f ("tracepoint: Optimize using static_call()") Reported-by: Stefan Metzmacher <metze@samba.org>
tested-by: Stefan Metzmacher <metze@samba.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Avoid synchronize_rcu_tasks_rude() call when not necessary
synchronize_rcu_tasks_rude() triggers IPIs and forces rescheduling on
all CPUs. It is a costly operation and, when targeting nohz_full CPUs,
very disrupting (hence the name). So avoid calling it when 'old_hash'
doesn't need to be freed.
Currently the histogram logic allows the user to write "cpu" in as an
event field, and it will record the CPU that the event happened on.
The problem with this is that there's a lot of events that have "cpu"
as a real field, and using "cpu" as the CPU it ran on, makes it
impossible to run histograms on the "cpu" field of events.
For example, if I want to have a histogram on the count of the
workqueue_queue_work event on its cpu field, running:
Change the command to "common_cpu" as no event should have "common_*"
fields as that's a reserved name for fields used by all events. And
this makes sense here as common_cpu would be a field used by all events.
Now we can even do:
># echo 'hist:keys=common_cpu,cpu if cpu < 100' > events/workqueue/workqueue_queue_work/trigger
># cat events/workqueue/workqueue_queue_work/hist
# event histogram
#
# trigger info: hist:keys=common_cpu,cpu:vals=hitcount:sort=hitcount:size=2048 if cpu < 100 [active]
#
Now for backward compatibility, I added a trick. If "cpu" is used, and
the field is not found, it will fall back to "common_cpu" and work as
it did before. This way, it will still work for old programs that use
"cpu" to get the actual CPU, but if the event has a "cpu" as a field, it
will get that event's "cpu" field, which is probably what it wants
anyway.
I updated the tracefs/README to include documentation about both the
common_timestamp and the common_cpu. This way, if that text is present in
the README, then an application can know that common_cpu is supported over
just plain "cpu".
Link: https://lkml.kernel.org/r/20210721110053.26b4f641@oasis.local.home Cc: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Fixes: 8b7622bf94a44 ("tracing: Add cpu field for hist triggers") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The reason is that the dynamic events array keeps track of the field
position of the fields array, via the field_pos variable in the
synth_field structure. Unfortunately, that field is a boolean for some
reason, which means any field_pos greater than 1 will be a bug (in this
case it was 2).
Link: https://lkml.kernel.org/r/20210721191008.638bce34@oasis.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Fixes: bd82631d7ccdc ("tracing: Add support for dynamic strings to synthetic events") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Haoran Luo [Wed, 21 Jul 2021 14:12:07 +0000 (14:12 +0000)]
tracing: Fix bug in rb_per_cpu_empty() that might cause deadloop.
The "rb_per_cpu_empty()" misinterpret the condition (as not-empty) when
"head_page" and "commit_page" of "struct ring_buffer_per_cpu" points to
the same buffer page, whose "buffer_data_page" is empty and "read" field
is non-zero.
An error scenario could be constructed as followed (kernel perspective):
1. All pages in the buffer has been accessed by reader(s) so that all of
them will have non-zero "read" field.
2. Read and clear all buffer pages so that "rb_num_of_entries()" will
return 0 rendering there's no more data to read. It is also required
that the "read_page", "commit_page" and "tail_page" points to the same
page, while "head_page" is the next page of them.
3. Invoke "ring_buffer_lock_reserve()" with large enough "length"
so that it shot pass the end of current tail buffer page. Now the
"head_page", "commit_page" and "tail_page" points to the same page.
4. Discard current event with "ring_buffer_discard_commit()", so that
"head_page", "commit_page" and "tail_page" points to a page whose buffer
data page is now empty.
When the error scenario has been constructed, "tracing_read_pipe" will
be trapped inside a deadloop: "trace_empty()" returns 0 since
"rb_per_cpu_empty()" returns 0 when it hits the CPU containing such
constructed ring buffer. Then "trace_find_next_entry_inc()" always
return NULL since "rb_num_of_entries()" reports there's no more entry
to read. Finally "trace_seq_to_user()" returns "-EBUSY" spanking
"tracing_read_pipe" back to the start of the "waitagain" loop.
I've also written a proof-of-concept script to construct the scenario
and trigger the bug automatically, you can use it to trace and validate
my reasoning above:
Tests has been carried out on linux kernel 5.14-rc2
(2734d6c1b1a089fb593ef6a23d4b70903526fe0c), my fixed version
of kernel (for testing whether my update fixes the bug) and
some older kernels (for range of affected kernels). Test result is
also attached to the proof-of-concept repository.
Merge tag 'perf-tools-fixes-for-v5.14-2021-07-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Skip invalid hybrid PMU on hybrid systems when the atom (little) CPUs
are offlined.
- Fix 'perf test' problems related to the recently added hybrid
(BIG/little) code.
- Split ARM's coresight (hw tracing) decode by aux records to avoid
fatal decoding errors.
- Fix add event failure in 'perf probe' when running 32-bit perf in a
64-bit kernel.
- Fix 'perf sched record' failure when CONFIG_SCHEDSTATS is not set.
- Fix memory and refcount leaks detected by ASAn when running 'perf
test', should be clean of warnings now.
- Remove broken definition of __LITTLE_ENDIAN from tools'
linux/kconfig.h, which was breaking the build in some systems.
- Cast PTHREAD_STACK_MIN to int as it may turn into 'long
sysconf(__SC_THREAD_STACK_MIN_VALUE), breaking the build in some
systems.
- Fix libperf build error with LIBPFM4=1.
- Sync UAPI files changed by the memfd_secret new syscall.
* tag 'perf-tools-fixes-for-v5.14-2021-07-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (35 commits)
perf sched: Fix record failure when CONFIG_SCHEDSTATS is not set
perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel
perf data: Close all files in close_dir()
perf probe-file: Delete namelist in del_events() on the error path
perf test bpf: Free obj_buf
perf trace: Free strings in trace__parse_events_option()
perf trace: Free syscall tp fields in evsel->priv
perf trace: Free syscall->arg_fmt
perf trace: Free malloc'd trace fields on exit
perf lzma: Close lzma stream on exit
perf script: Fix memory 'threads' and 'cpus' leaks on exit
perf script: Release zstd data
perf session: Cleanup trace_event
perf inject: Close inject.output on exit
perf report: Free generated help strings for sort option
perf env: Fix memory leak of cpu_pmu_caps
perf test maps__merge_in: Fix memory leak of maps
perf dso: Fix memory leak in dso__new_map()
perf test event_update: Fix memory leak of unit
perf test event_update: Fix memory leak of evlist
...
Merge tag 'xfs-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Darrick Wong:
"A few fixes for issues in the new online shrink code, additional
corrections for my recent bug-hunt w.r.t. extent size hints on
realtime, and improved input checking of the GROWFSRT ioctl.
IOW, the usual 'I somehow got bored during the merge window and
resumed auditing the farther reaches of xfs':
- Fix shrink eligibility checking when sparse inode clusters enabled
- Reset '..' directory entries when unlinking directories to prevent
verifier errors if fs is shrinked later
- Don't report unusable extent size hints to FSGETXATTR
- Don't warn when extent size hints are unusable because the sysadmin
configured them that way
- Fix insufficient parameter validation in GROWFSRT ioctl
- Fix integer overflow when adding rt volumes to filesystem"
* tag 'xfs-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: detect misaligned rtinherit directory extent size hints
xfs: fix an integer overflow error in xfs_growfs_rt
xfs: improve FSGROWFSRT precondition checking
xfs: don't expose misaligned extszinherit hints to userspace
xfs: correct the narrative around misaligned rtinherit/extszinherit dirs
xfs: reset child dir '..' entry when unlinking child
xfs: check for sparse inode clusters that cross new EOAG when shrinking
Merge tag 'iomap-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull iomap fixes from Darrick Wong:
"A handful of bugfixes for the iomap code.
There's nothing especially exciting here, just fixes for UBSAN (not
KASAN as I erroneously wrote in the tag message) warnings about
undefined behavior in the SEEK_DATA/SEEK_HOLE code, and some
reshuffling of per-page block state info to fix some problems with
gfs2.
- Fix KASAN warnings due to integer overflow in SEEK_DATA/SEEK_HOLE
- Fix assertion errors when using inlinedata files on gfs2"
* tag 'iomap-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
iomap: Don't create iomap_page objects in iomap_page_mkwrite_actor
iomap: Don't create iomap_page objects for inline files
iomap: Permit pages without an iop to enter writeback
iomap: remove the length variable in iomap_seek_hole
iomap: remove the length variable in iomap_seek_data
Merge tag 'kbuild-fixes-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- Restore the original behavior of scripts/setlocalversion when
LOCALVERSION is set to empty.
- Show Kconfig prompts even for 'make -s'
- Fix the combination of COFNIG_LTO_CLANG=y and CONFIG_MODVERSIONS=y
for older GNU Make versions
* tag 'kbuild-fixes-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
Documentation: Fix intiramfs script name
Kbuild: lto: fix module versionings mismatch in GNU make 3.X
kbuild: do not suppress Kconfig prompts for silent build
scripts/setlocalversion: fix a bug when LOCALVERSION is empty
Robert Richter [Thu, 15 Jul 2021 09:26:02 +0000 (11:26 +0200)]
Documentation: Fix intiramfs script name
Documentation was not changed when renaming the script in commit 80e715a06c2d ("initramfs: rename gen_initramfs_list.sh to
gen_initramfs.sh"). Fixing this.
Basically does:
$ sed -i -e s/gen_initramfs_list.sh/gen_initramfs.sh/g $(git grep -l gen_initramfs_list.sh)
Fixes: 80e715a06c2d ("initramfs: rename gen_initramfs_list.sh to gen_initramfs.sh") Signed-off-by: Robert Richter <rrichter@amd.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Kbuild: lto: fix module versionings mismatch in GNU make 3.X
When building modules(CONFIG_...=m), I found some of module versions
are incorrect and set to 0.
This can be found in build log for first clean build which shows
WARNING: EXPORT symbol "XXXX" [drivers/XXX/XXX.ko] version generation failed,
symbol will not be versioned.
But in second build(incremental build), the WARNING disappeared and the
module version becomes valid CRC and make someone who want to change
modules without updating kernel image can't insert their modules.
The problematic code is
+ $(foreach n, $(filter-out FORCE,$^), \
+ $(if $(wildcard $(n).symversions), \
+ ; cat $(n).symversions >> $@.symversions))
`foreach n` shows nothing to `cat` into $(n).symversions because
`if $(wildcard $(n).symversions)` return nothing, but actually
they do exist during this line was executed.
-rw-r--r-- 1 root root 168580 Jun 13 19:10 fs/notify/fsnotify.o
-rw-r--r-- 1 root root 111 Jun 13 19:10 fs/notify/fsnotify.o.symversions
The reason is the $(n).symversions are generated at runtime, but
Makefile wildcard function expends and checks the file exist or not
during parsing the Makefile.
Thus fix this by use `test` shell command to check the file
existence in runtime.
Rebase from both:
1. [https://lore.kernel.org/lkml/20210616080252.32046-1-lecopzer.chen@mediatek.com/]
2. [https://lore.kernel.org/lkml/20210702032943.7865-1-lecopzer.chen@mediatek.com/]
kbuild: do not suppress Kconfig prompts for silent build
When a new CONFIG option is available, Kbuild shows a prompt to get
the user input.
$ make
[ snip ]
Core Scheduling for SMT (SCHED_CORE) [N/y/?] (NEW)
This is the only interactive place in the build process.
Commit 174a1dcc9642 ("kbuild: sink stdout from cmd for silent build")
suppressed Kconfig prompts as well because syncconfig is invoked by
the 'cmd' macro. You cannot notice the fact that Kconfig is waiting
for the user input.
Use 'kecho' to show the equivalent short log without suppressing stdout
from sub-make.
scripts/setlocalversion: fix a bug when LOCALVERSION is empty
The commit 042da426f8eb ("scripts/setlocalversion: simplify the short
version part") reduces indentation. Unfortunately, it also changes behavior
in a subtle way - if the user has empty "LOCALVERSION" variable, the plus
sign is appended to the kernel version. It wasn't appended before.
This patch reverts to the old behavior - we append the plus sign only if
the LOCALVERSION variable is not set.
Fixes: 042da426f8eb ("scripts/setlocalversion: simplify the short version part") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Yang Jihong [Tue, 13 Jul 2021 11:23:58 +0000 (19:23 +0800)]
perf sched: Fix record failure when CONFIG_SCHEDSTATS is not set
The tracepoints trace_sched_stat_{wait, sleep, iowait} are not exposed to user
if CONFIG_SCHEDSTATS is not set, "perf sched record" records the three events.
As a result, the command fails.
Error: File /sys/kernel/tracing/events/sched/sched_stat_wait not found.
Hint: Perhaps this kernel misses some CONFIG_ setting to enable this feature?.
Run 'perf list' for a list of valid events
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-e, --event <event> event selector. use 'perf list' to list available events
Solution:
Check whether schedstat tracepoints are exposed. If no, these events are not recorded.
After:
# perf sched record sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.163 MB perf.data (1091 samples) ]
# perf sched report
run measurement overhead: 4736 nsecs
sleep measurement overhead: 9059979 nsecs
the run test took 999854 nsecs
the sleep test took 8945271 nsecs
nr_run_events: 716
nr_sleep_events: 785
nr_wakeup_events: 0
...
------------------------------------------------------------
Fixes: 2a09b5de235a6 ("sched/fair: do not expose some tracepoints to user if CONFIG_SCHEDSTATS is not set") Signed-off-by: Yang Jihong <yangjihong1@huawei.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Yafang Shao <laoar.shao@gmail.com> Link: http://lore.kernel.org/lkml/20210713112358.194693-1-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Yang Jihong [Thu, 15 Jul 2021 06:37:23 +0000 (14:37 +0800)]
perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel
The "address" member of "struct probe_trace_point" uses long data type.
If kernel is 64-bit and perf program is 32-bit, size of "address"
variable is 32 bits.
As a result, upper 32 bits of address read from kernel are truncated, an
error occurs during address comparison in kprobe_warn_out_range().
Before:
# perf probe -a schedule
schedule is out of .text, skip it.
Error: Failed to add events.
Solution:
Change data type of "address" variable to u64 and change corresponding
address printing and value assignment.
After:
# perf.new.new probe -a schedule
Added new event:
probe:schedule (on schedule)
Signed-off-by: Yang Jihong <yangjihong1@huawei.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: Ian Rogers <irogers@google.com> Cc: Jianlin Lv <jianlin.lv@arm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Li Huafei <lihuafei1@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lore.kernel.org/lkml/20210715063723.11926-1-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's not clear why, but it causes unexplained problems in entirely
unrelated xfs code. The most likely explanation is some slab
corruption, possibly triggered due to CONFIG_SLUB_DEBUG_ON. See [1].
It ends up having a few other problems too, like build errors on
arch/arc, and Geert reporting it using much more memory on m68k [3] (it
probably does so elsewhere too, but it is probably just more noticeable
on m68k).
The architecture issues (both build and memory use) are likely just
because this change effectively force-enabled STACKDEPOT (along with a
very bad default value for the stackdepot hash size). But together with
the xfs issue, this all smells like "this commit was not ready" to me.
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"One core fix for an oops which can occur if the error handling thread
fails to start for some reason and the driver is removed.
The other fixes are all minor ones in drivers"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ufs: core: Add missing host_lock in ufshcd_vops_setup_xfer_req()
scsi: mpi3mr: Fix W=1 compilation warnings
scsi: pm8001: Clean up kernel-doc and comments
scsi: zfcp: Report port fc_security as unknown early during remote cable pull
scsi: core: Fix bad pointer dereference when ehandler kthread is invalid
scsi: fas216: Fix a build error
scsi: core: Fix the documentation of the scsi_execute() time parameter
Merge tag '5.14-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Eight cifs/smb3 fixes, including three for stable.
Three are DFS related fixes, and two to fix problems pointed out by
static checkers"
* tag '5.14-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: do not share tcp sessions of dfs connections
SMB3.1.1: fix mount failure to some servers when compression enabled
cifs: added WARN_ON for all the count decrements
cifs: fix missing null session check in mount
cifs: handle reconnect of tcon when there is no cached dfs referral
cifs: fix the out of range assignment to bit fields in parse_server_interfaces
cifs: Do not use the original cruid when following DFS links for multiuser mounts
cifs: use the expiry output of dns_query to schedule next resolution
Merge tag 'linux-kselftest-kunit-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kunit fixes from Shuah Khan:
"Fixes to kunit tool and documentation:
- fix asserts on older python versions
- fixes to misleading error messages when TAP header format is
incorrect or when file is missing
- documentation fix: drop obsolete information about uml_abort
coverage
- remove unnecessary annotations"
* tag 'linux-kselftest-kunit-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
kunit: tool: Assert the version requirement
kunit: tool: remove unnecessary "annotations" import
Documentation: kunit: drop obsolete note about uml_abort for coverage
kunit: tool: Fix error messages for cases of no tests and wrong TAP header
Merge tag 'linux-kselftest-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest fix from Shuah Khan:
"A fix to memory-hotplug hot-remove test to stop spamming logs with
dump_page() entries and slowing the system down to a crawl"
* tag 'linux-kselftest-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
selftests: memory-hotplug: avoid spamming logs with dump_page(), ratio limit hot-remove error test
Merge tag 'trace-v5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Fix the histogram logic from possibly crashing the kernel
Working on the histogram code, I found that if you dereference a char
pointer in a trace event that happens to point to user space, it can
crash the kernel, as it does no checks of that pointer. I have code
coming that will do this better, so just remove this ability to treat
character pointers in trace events as stings in the histogram"
* tag 'trace-v5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Do not reference char * as a string in histograms
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"The bulk of the diffstat consists of changes to our uaccess routines
so that they fall back to bytewise copying prior to reporting complete
failure when the initial (multi-byte) access faults.
However, the most disappointing change here is that we've had to bump
ARCH_DMA_MINALIGN back to 128 bytes thanks to Qualcomm's "Kryo" CPU,
which ended up in the MSM8996 mobile SoC. Still, at least we're now
aware of this design and one of the hardware designers confirmed the
L2 cacheline size for us.
Summary:
- Fix instrumentation annotations for entry code
- Ensure kernel MTE state is restored correctly on resume from suspend
- Fix MTE fault from new strlen() routine
- Fallback to byte-wise accesses on initial uaccess fault
- Bump Clang requirement for BTI
- Revert ARCH_DMA_MINALIGN back to 128 bytes (shakes fist at Qualcomm)"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: entry: fix KCOV suppression
arm64: entry: add missing noinstr
arm64: mte: fix restoration of GCR_EL1 from suspend
arm64: Avoid premature usercopy failure
arm64: Restrict ARM64_BTI_KERNEL to clang 12.0.0 and newer
Revert "arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)"
arm64: Add missing header <asm/smp.h> in two files
arm64: fix strlen() with CONFIG_KASAN_HW_TAGS
Stefan Wahren [Sat, 10 Jul 2021 11:04:55 +0000 (13:04 +0200)]
ARM: multi_v7_defconfig: Make NOP_USB_XCEIV driver built-in
The usage of usb-nop-xceiv PHY on Raspberry Pi boards with BCM283x has
been a "regression source" a lot of times. The last case is breakage of
USB mass storage boot has been commit e590474768f1 ("driver core: Set
fw_devlink=on by default") for multi_v7_defconfig. As long as
NOP_USB_XCEIV is configured as module, the dwc2 USB driver defer probing
endlessly and prevent booting from USB mass storage device. So make
the driver built-in as in bcm2835_defconfig and arm64/defconfig.
The platform lost the framebuffer due to a commit solving a
circular dependency in v5.14-rc1, so add it back in by explicitly
selecting the framebuffer.
The U8500 has also gained a few systems using touchscreens from
Cypress, Melfas and Zinitix so add these at the same time as
we're updating the defconfig anyway.
projects / mirror_ubuntu-kernels.git / log