| Age | Commit message (Collapse) | Author |
|---|
|
Since the shared trace_probe_log variable can be accessed and
modified via probe event create operation of kprobe_events,
uprobe_events, and dynamic_events, it should be protected.
In the dynamic_events, all operations are serialized by
`dyn_event_ops_mutex`. But kprobe_events and uprobe_events
interfaces are not serialized.
To solve this issue, introduces dyn_event_create(), which runs
create() operation under the mutex, for kprobe_events and
uprobe_events. This also uses lockdep to check the mutex is
held when using trace_probe_log* APIs.
Link: https://lore.kernel.org/all/174684868120.551552.3068655787654268804.stgit@devnote2/
Reported-by: Paul Cacheux <paulcacheux@gmail.com>
Closes: https://lore.kernel.org/all/20250510074456.805a16872b591e2971a4d221@kernel.org/
Fixes: ab105a4fb894 ("tracing: Use tracing error_log with probe events")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
|
|
This patch introduces a new set of kfuncs for working with dynptrs in
BPF programs, enabling reading variable-length user or kernel data
into dynptr directly. To enable memory-safety, verifier allows only
constant-sized reads via existing bpf_probe_read_{user|kernel} etc.
kfuncs, dynptr-based kfuncs allow dynamically-sized reads without memory
safety shortcomings.
The following kfuncs are introduced:
* `bpf_probe_read_kernel_dynptr()`: probes kernel-space data into a dynptr
* `bpf_probe_read_user_dynptr()`: probes user-space data into a dynptr
* `bpf_probe_read_kernel_str_dynptr()`: probes kernel-space string into
a dynptr
* `bpf_probe_read_user_str_dynptr()`: probes user-space string into a
dynptr
* `bpf_copy_from_user_dynptr()`: sleepable, copies user-space data into
a dynptr for the current task
* `bpf_copy_from_user_str_dynptr()`: sleepable, copies user-space string
into a dynptr for the current task
* `bpf_copy_from_user_task_dynptr()`: sleepable, copies user-space data
of the task into a dynptr
* `bpf_copy_from_user_task_str_dynptr()`: sleepable, copies user-space
string of the task into a dynptr
The implementation is built on two generic functions:
* __bpf_dynptr_copy
* __bpf_dynptr_copy_str
These functions take function pointers as arguments, enabling the
copying of data from various sources, including both kernel and user
space.
Use __always_inline for generic functions and callbacks to make sure the
compiler doesn't generate indirect calls into callbacks, which is more
expensive, especially on some kernel configurations. Inlining allows
compiler to put direct calls into all the specific callback implementations
(copy_user_data_sleepable, copy_user_data_nofault, and so on).
Reviewed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Link: https://lore.kernel.org/r/20250512205348.191079-3-mykyta.yatsenko5@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
Make sure trace_probe_log_clear is called in the tracing
eprobe code path, matching the trace_probe_log_init call.
Link: https://lore.kernel.org/all/20250504-fix-trace-probe-log-race-v3-1-9e99fec7eddc@gmail.com/
Signed-off-by: Paul Cacheux <paulcacheux@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
|
|
When CONFIG_PROVE_RCU_LIST is enabled, fprobe triggers the following
warning:
WARNING: suspicious RCU usage
kernel/trace/fprobe.c:457 RCU-list traversed in non-reader section!!
other info that might help us debug this:
#1: ffffffff863c4e08 (fprobe_mutex){+.+.}-{4:4}, at: fprobe_module_callback+0x7b/0x8c0
Call Trace:
fprobe_module_callback
notifier_call_chain
blocking_notifier_call_chain
This warning occurs because fprobe_remove_node_in_module() traverses an
RCU list using RCU primitives without holding an RCU read lock. However,
the function is only called from fprobe_module_callback(), which holds
the fprobe_mutex lock that provides sufficient protection for safely
traversing the list.
Fix the warning by specifying the locking design to the
CONFIG_PROVE_RCU_LIST mechanism. Add the lockdep_is_held() argument to
hlist_for_each_entry_rcu() to inform the RCU checker that fprobe_mutex
provides the required protection.
Link: https://lore.kernel.org/all/20250410-fprobe-v1-1-068ef5f41436@debian.org/
Fixes: a3dc2983ca7b90 ("tracing: fprobe: Cleanup fprobe hash when module unloading")
Signed-off-by: Breno Leitao <leitao@debian.org>
Tested-by: Antonio Quartulli <antonio@mandelbit.com>
Tested-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
|
|
Adding support to retrieve ref_ctr_offset for uprobe perf link,
which got somehow omitted from the initial uprobe link info changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/bpf/20250509153539.779599-2-jolsa@kernel.org
|
|
There are applications that have it hard coded to write into the top level
trace_marker instance (/sys/kernel/tracing/trace_marker). This can be
annoying if a profiler is using that instance for other work, or if it
needs all writes to go into a new instance.
A new option is created called "copy_trace_marker". By default, the top
level has this set, as that is the default buffer that writing into the
top level trace_marker file will go to. But now if an instance is created
and sets this option, all writes into the top level trace_marker will also
be written into that instance buffer just as if an application were to
write into the instance's trace_marker file.
If the top level instance disables this option, then writes to its own
trace_marker and trace_marker_raw files will not go into its buffer.
If no instance has this option set, then the write will return an error
and errno will contain ENODEV.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250508095639.39f84eda@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Add a helper function called handle_dereference_arg() to replace the logic
that is identical in two locations of test_event_printk().
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250507191703.5dd8a61d@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
There's several functions that have "goto out;" where the label out is just:
out:
return ret;
Simplify the code by just doing the return in the location and removing
all the out labels and jumps.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Link: https://lore.kernel.org/20250507145456.121186494@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
According to trigger_data_alloc() doc, trigger_data_free() should be
used to free an event_trigger_data object. This fixes a mismatch introduced
when kzalloc was replaced with trigger_data_alloc without updating
the corresponding deallocation calls.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Link: https://lore.kernel.org/20250507145455.944453325@goodmis.org
Link: https://lore.kernel.org/20250318112737.4174-1-linmq006@gmail.com
Fixes: e1f187d09e11 ("tracing: Have existing event_command.parse() implementations use helpers")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
[ SDR: Changed event_trigger_alloc/free() to trigger_data_alloc/free() ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The function event_trigger_alloc() creates an event_trigger_data
descriptor and states that it needs to be freed via event_trigger_free().
This is incorrect, it needs to be freed by trigger_data_free() as
event_trigger_free() adds ref counting.
Rename event_trigger_alloc() to trigger_data_alloc() and state that it
needs to be freed via trigger_data_free(). This naming convention
was introducing bugs.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Link: https://lore.kernel.org/20250507145455.776436410@goodmis.org
Fixes: 86599dbe2c527 ("tracing: Add helper functions to simplify event_command.parse() callback handling")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
strncpy() is deprecated for NUL-terminated destination buffers and must
be replaced by strscpy().
See issue: https://github.com/KSPP/linux/issues/90
Link: https://lore.kernel.org/20250507133837.19640-1-devaanshk840@gmail.com
Signed-off-by: Devaansh Kumar <devaanshk840@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The trace_array_cpu had a "buffer_page" field that was originally going to
be used as a backup page for the ring buffer. But the ring buffer has its
own way of reusing pages and this field was never used.
Remove it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.738849456@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
tracer
The irqsoff tracer uses the per CPU "disabled" field to prevent corruption
of the accounting when it starts to trace interrupts disabled, but there's
a slight race that could happen if for some reason it was called twice.
Use atomic_inc_return() instead.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.567884756@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The per CPU "disabled" counter is used for the latency tracers and stack
tracers to make sure that their accounting isn't messed up by an NMI or
interrupt coming in and affecting the same CPU data. But the counter is an
atomic_t type. As it only needs to synchronize against the current CPU,
switch it over to local_t type.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.394925376@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The branch tracer currently checks the per CPU "disabled" field to know if
tracing is enabled or not for the CPU. As the "disabled" value is not used
anymore to turn of tracing generically, use tracing_tracer_is_on_cpu()
instead.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.224658526@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Add the function ring_buffer_record_is_on_cpu() that returns true if the
ring buffer for a give CPU is writable and false otherwise.
Also add tracer_tracing_is_on_cpu() to return if the ring buffer for a
given CPU is writeable for a given trace_array.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212236.059853898@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
Do not bother setting the per CPU disabled flag of the array_buffer data
to use to determine what CPUs can write to the buffer and only rely on the
ring buffer code itself to disabled it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212235.885452497@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
Do not bother disabling the function graph tracer if the per CPU disabled
field is set. Just record as normal. If tracing is disabled in the ring
buffer it will not be recorded.
Also, when tracing is enabled again, it will not drop the return call of
the function.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212235.715752008@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
The kdb_ftdump() function iterates over all the current tracing CPUs and
increments the "disabled" counter before doing the dump, and decrements it
afterward.
As the disabled flag can be ignored, doing this today is not reliable.
Instead, simply call tracer_tracing_off() and then tracer_tracing_on() to
disable and then enabled the entire ring buffer in one go!
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Thompson <danielt@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/20250505212235.549033722@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
ftrace_dump_one()
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
The ftrace_dump_one() function iterates over all the current tracing CPUs and
increments the "disabled" counter before doing the dump, and decrements it
afterward.
As the disabled flag can be ignored, doing this today is not reliable.
Instead use the new tracer_tracing_disable() that calls into the ring
buffer code to do the disabling.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212235.381188238@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Allow a tracer to disable writing to its buffer for a temporary amount of
time and re-enable it.
The tracer_tracing_disable() will disable writing to the trace array
buffer, and requires a tracer_tracing_enable() to re-enable it.
The difference between tracer_tracing_disable() and tracer_tracing_off()
is that the disable version can nest, and requires as many enable() calls
as disable() calls to re-enable the buffer. Where as the off() function
can be called multiple times and only requires a singe tracer_tracing_on()
to re-enable the buffer.
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Thompson <danielt@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/20250505212235.210330010@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
if it works under NMI and doesn't use any context-dependent things,
should be fine for any program type. The detailed discussion is in [1].
[1] https://lore.kernel.org/all/CAEf4Bza6gK3dsrTosk6k3oZgtHesNDSrDd8sdeQ-GiS6oJixQg@mail.gmail.com/
Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/bpf/20250506061434.94277-2-yangfeng59949@163.com
|
|
The ignore_pid boolean on the per CPU data descriptor is updated at
sched_switch when a new task is scheduled in. If the new task is to be
ignored, it is set to true, otherwise it is set to false. The current task
should always have the correct value as it is updated when the task is
scheduled in.
Instead of breaking up the read of this value, which requires preemption
to be disabled, just use this_cpu_read() which gives a snapshot of the
value. Since the value will always be correct for a given task (because
it's updated at sched switch) it doesn't need preemption disabled.
This will also allow trace events to be called with preemption enabled.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212235.038958766@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The per CPU "disabled" value was the original way to disable tracing when
the tracing subsystem was first created. Today, the ring buffer
infrastructure has its own way to disable tracing. In fact, things have
changed so much since 2008 that many things ignore the disable flag.
There's no reason for the function tracer to check it, if tracing is
disabled, the ring buffer will not record the event anyway.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212234.868972758@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The mmiotracer referenced the per CPU array_buffer->data descriptor but
never actually used it. Remove the references to it.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250505212234.696945463@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Allocate kernel memory for processing CPU string
(/sys/kernel/tracing/osnoise/cpus) also in osnoise_cpus_write to allow
the writing of a CPU string of an arbitrary length.
This replaces the 256-byte buffer, which is insufficient with the rising
number of CPUs. For example, if I wanted to measure on every even CPU
on a system with 256 CPUs, the string would be 456 characters long.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250425091839.343289-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The structure ftrace_func_mapper only contains a single field and that is
a ftrace_hash. It is used to abstract it out from a normal hash to control
users of how it gets modified.
The freeing of a ftrace_func_mapper structure is:
free_ftrace_hash(&mapper->hash);
Without context, this looks like a bug. It should be commented that it is
not a bug and it is freed this way.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/20250416165420.5c717420@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Depth is stored as int because the code uses negative values to break
out of iterations. But what is recorded is always zero or positive. So
expose it as unsigned int instead of int.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250412221847.17310-3-iii@linux.ibm.com
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The function graph infrastructure uses subops of the function tracer.
These are not shown in enabled_functions. Add a "subops:" section to the
enabled_functions line to show what functions are attached via subops. If
the subops is from the function_graph infrastructure, then show the entry
and return callbacks that are attached.
Here's an example of the output:
schedule_on_each_cpu (1) tramp: 0xffffffffc03ef000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 subops: {ent:trace_graph_entry+0x0/0x20 ret:trace_graph_return+0x0/0x150}
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250410153830.5d97f108@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The last remaining user of vfs_submount() (tracefs) is easy to convert
to fs_context_for_submount(); do that and bury that thing, along with
SB_SUBMOUNT
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Tested-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
If one wants to trace the name of the task that wakes up a process and
pass that to the synthetic events, there's nothing currently that lets the
synthetic events do that. Add a "common_comm" to the histogram logic that
allows histograms save the current->comm as a variable that can be passed
through and added to a synthetic event:
# cd /sys/kernel/tracing
# echo 's:wake_lat char[] waker; char[] wakee; u64 delta;' >> dynamic_events
# echo 'hist:keys=pid:comm=common_comm:ts=common_timestamp.usecs if !(common_flags & 0x18)' > events/sched/sched_waking/trigger
# echo 'hist:keys=next_pid:wake_comm=$comm:delta=common_timestamp.usecs-$ts:onmatch(sched.sched_waking).trace(wake_lat,$wake_comm,next_comm,$delta)' > events/sched/sched_switch/trigger
The above will create a synthetic trace event that will save both the name
of the waker and the wakee but only if the wakeup did not happen in a hard
or soft interrupt context.
The "common_comm" is used to save the task->comm at the time of the
initial event and is passed via the "comm" variable to the second event,
and that is saved as the "waker" field in the "wake_lat" synthetic event.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250407154912.3c6c6246@gandalf.local.home
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The histogram trigger has three somewhat large arrays on the kernel stack:
unsigned long entries[HIST_STACKTRACE_DEPTH];
u64 var_ref_vals[TRACING_MAP_VARS_MAX];
char compound_key[HIST_KEY_SIZE_MAX];
Checking the function event_hist_trigger() stack frame size, it currently
uses 816 bytes for its stack frame due to these variables!
Instead, allocate a per CPU structure that holds these arrays for each
context level (normal, softirq, irq and NMI). That is, each CPU will have
4 of these structures. This will be allocated when the first histogram
trigger is enabled and freed when the last is disabled. When the
histogram callback triggers, it will request this structure. The request
will disable preemption, get the per CPU structure at the index of the
per CPU variable, and increment that variable.
The callback will use the arrays in this structure to perform its work and
then release the structure. That in turn will simply decrement the per CPU
index and enable preemption.
Moving the variables from the kernel stack to the per CPU structure brings
the stack frame of event_hist_trigger() down to just 112 bytes.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Link: https://lore.kernel.org/20250407123851.74ea8d58@gandalf.local.home
Fixes: 067fe038e70f6 ("tracing: Add variable reference handling to hist triggers")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The add_to_key() function tests if the key is a string or some data. If
it's a string it does some further calculations of the string size (still
truncating it to the max size it can be), and calls strncpy().
If the key isn't as string it calls memcpy(). The interesting point is
that both use the exact same parameters:
strncpy(compound_key + key_field->offset, (char *)key, size);
} else
memcpy(compound_key + key_field->offset, key, size);
As strncpy() is being used simply as a memcpy() for a string, and since
strncpy() is deprecated, just call memcpy() for both memory and string
keys.
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/20250403210637.1c477d4a@gandalf.local.home
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
When the "fields" option is set in a trace instance, it ignores the "print fmt"
portion of the trace event and just prints the raw fields defined by the
TP_STRUCT__entry() of the TRACE_EVENT() macro.
The preempt_disable/enable and irq_disable/enable events record only the
caller offset from _stext to save space in the ring buffer. Even though
the "fields" option only prints the fields, it also tries to print what
they represent too, which includes function names.
Add a check in the output of the event field printing to see if the field
name is "caller_offs" or "parent_offs" and then print the function at the
offset from _stext of that field.
Instead of just showing:
irq_disable: caller_offs=0xba634d (12215117) parent_offs=0x39d10e2 (60625122)
Show:
irq_disable: caller_offs=trace_hardirqs_off.part.0+0xad/0x130 0xba634d (12215117) parent_offs=_raw_spin_lock_irqsave+0x62/0x70 0x39d10e2 (60625122)
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250506105131.4b6089a9@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Add adjustments to the values of the "fields" output if the buffer is a
persistent ring buffer to adjust the addresses to both the kernel core and
kernel modules if they match a module in the persistent memory and that
module is also loaded.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250325185619.54b85587@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The trace_adjust_address() will take a given address and examine the
persistent ring buffer to see if the address matches a module that is
listed there. If it does not, it will just adjust the value to the core
kernel delta. But if the address was for something that was not part of
the core kernel text or data it should not be adjusted.
Check the result of the adjustment and only return the adjustment if it
lands in the current kernel text or data. If not, return the original
address.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250506102300.0ba2f9e0@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
When the "fields" option is enabled, the "print fmt" of the trace event is
ignored and only the fields are printed. But some fields contain function
pointers. Instead of just showing the hex value in this case, show the
function name when possible:
Instead of having:
# echo 1 > options/fields
# cat trace
[..]
kmem_cache_free: call_site=0xffffffffa9afcf31 (-1448095951) ptr=0xffff888124452910 (-131386736039664) name=kmemleak_object
Have it output:
kmem_cache_free: call_site=rcu_do_batch+0x3d1/0x14a0 (-1768960207) ptr=0xffff888132ea5ed0 (854220496) name=kmemleak_object
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250325213919.624181915@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Now that module addresses are saved in the persistent ring buffer, their
addresses can be used to adjust the address in the persistent ring buffer
to the address of the module that is currently loaded.
Instead of blindly using the text_delta that only works for core kernel
code, call the trace_adjust_address() that will see if the address matches
an address saved in the persistent ring buffer, and then uses that against
the matching module if it is loaded.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250506111648.5df7f3ec@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The block layer bounce buffering support is unused now, remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250505081138.3435992-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
Currently the calling conventions for ->d_automount() instances have
an odd wart - returned new mount to be attached is expected to have
refcount 2.
That kludge is intended to make sure that mark_mounts_for_expiry() called
before we get around to attaching that new mount to the tree won't decide
to take it out. finish_automount() drops the extra reference after it's
done with attaching mount to the tree - or drops the reference twice in
case of error. ->d_automount() instances have rather counterintuitive
boilerplate in them.
There's a much simpler approach: have mark_mounts_for_expiry() skip the
mounts that are yet to be mounted. And to hell with grabbing/dropping
those extra references. Makes for simpler correctness analysis, at that...
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Acked-by: David Howells <dhowells@redhat.com>
Tested-by: David Howells <dhowells@redhat.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
On some paths in print_event_fields() it takes the trace_event_sem for
read, even though it should always be held when the function is called.
Remove the taking of that mutex and add a lockdep_assert_held_read() to
make sure the trace_event_sem is held when print_event_fields() is called.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250501224128.0b1f0571@batman.local.home
Fixes: 80a76994b2d88 ("tracing: Add "fields" option to show raw trace event fields")
Reported-by: syzbot+441582c1592938fccf09@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6813ff5e.050a0220.14dd7d.001b.GAE@google.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The function trace_adjust_address() is used to map addresses of modules
stored in the persistent memory and are also loaded in the current boot to
return the current address for the module.
If there's only one module entry, it will simply use that, otherwise it
performs a bsearch of the entry array to find the modules to offset with.
The issue is if there are no modules in the array. The code does not
account for that and ends up referencing the first element in the array
which does not exist and causes a crash.
If nr_entries is zero, exit out early as if this was a core kernel
address.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250501151909.65910359@gandalf.local.home
Fixes: 35a380ddbc653 ("tracing: Show last module text symbols in the stacktrace")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The check for a failed memory location is incorrectly checking
the wrong level of pointer indirection by checking !filter_hash
rather than !*filter_hash. Fix this.
Cc: asami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250422221335.89896-1-colin.i.king@gmail.com
Fixes: 0ae6b8ce200d ("ftrace: Fix accounting of subop hashes")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
syzbot reported this bug:
==================================================================
BUG: KASAN: slab-out-of-bounds in trace_seq_to_buffer kernel/trace/trace.c:1830 [inline]
BUG: KASAN: slab-out-of-bounds in tracing_splice_read_pipe+0x6be/0xdd0 kernel/trace/trace.c:6822
Write of size 4507 at addr ffff888032b6b000 by task syz.2.320/7260
CPU: 1 UID: 0 PID: 7260 Comm: syz.2.320 Not tainted 6.15.0-rc1-syzkaller-00301-g3bde70a2c827 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc3/0x670 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
__asan_memcpy+0x3c/0x60 mm/kasan/shadow.c:106
trace_seq_to_buffer kernel/trace/trace.c:1830 [inline]
tracing_splice_read_pipe+0x6be/0xdd0 kernel/trace/trace.c:6822
....
==================================================================
It has been reported that trace_seq_to_buffer() tries to copy more data
than PAGE_SIZE to buf. Therefore, to prevent this, we should use the
smaller of trace_seq_used(&iter->seq) and PAGE_SIZE as an argument.
Link: https://lore.kernel.org/20250422113026.13308-1-aha310510@gmail.com
Reported-by: syzbot+c8cd2d2c412b868263fb@syzkaller.appspotmail.com
Fixes: 3c56819b14b0 ("tracing: splice support for tracing_pipe")
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
Many conditional checks in switch-case are redundant
with bpf_base_func_proto and should be removed.
Regarding the permission checks bpf_base_func_proto:
The permission checks in bpf_prog_load (as outlined below)
ensure that the trace has both CAP_BPF and CAP_PERFMON capabilities,
thus enabling the use of corresponding prototypes
in bpf_base_func_proto without adverse effects.
bpf_prog_load
......
bpf_cap = bpf_token_capable(token, CAP_BPF);
......
if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
type != BPF_PROG_TYPE_CGROUP_SKB &&
!bpf_cap)
goto put_token;
......
if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON))
goto put_token;
......
Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20250423073151.297103-1-yangfeng59949@163.com
|
|
Cross-merge bpf and other fixes after downstream PRs.
No conflicts.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
The filter string testing uses strncpy_from_kernel/user_nofault() to
retrieve the string to test the filter against. The if() statement was
incorrect as it considered 0 as a fault, when it is only negative that it
faulted.
Running the following commands:
# cd /sys/kernel/tracing
# echo "filename.ustring ~ \"/proc*\"" > events/syscalls/sys_enter_openat/filter
# echo 1 > events/syscalls/sys_enter_openat/enable
# ls /proc/$$/maps
# cat trace
Would produce nothing, but with the fix it will produce something like:
ls-1192 [007] ..... 8169.828333: sys_openat(dfd: ffffffffffffff9c, filename: 7efc18359904, flags: 80000, mode: 0)
Link: https://lore.kernel.org/all/CAEf4BzbVPQ=BjWztmEwBPRKHUwNfKBkS3kce-Rzka6zvbQeVpg@mail.gmail.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20250417183003.505835fb@gandalf.local.home
Fixes: 77360f9bbc7e5 ("tracing: Add test for user space strings when filtering on string pointers")
Reported-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Reported-by: Mykyta Yatsenko <mykyta.yatsenko5@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
ftrace_graph_ent.depth is int, but ftrace_graph_ent_entry.depth is
unsigned long. This confuses trace-cmd on 64-bit big-endian systems and
makes it print a huge amount of spaces. Fix this by using unsigned int,
which has a matching size, instead.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/20250412221847.17310-2-iii@linux.ibm.com
Fixes: ff5c9c576e75 ("ftrace: Add support for function argument to graph tracer")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The maximum of the ftrace hash bits is made fls(32) in
register_ftrace_direct(), which seems illogical. So, we fix it by making
the max hash bits FTRACE_HASH_MAX_BITS instead.
Link: https://lore.kernel.org/20250413014444.36724-1-dongml2@chinatelecom.cn
Fixes: d05cb470663a ("ftrace: Fix modification of direct_function hash while in use")
Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
The subops processing creates new hashes when adding and removing subops.
There were some places that the old hashes that were replaced were not
freed and this caused some memory leaks.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250417135939.245b128d@gandalf.local.home
Fixes: 0ae6b8ce200d ("ftrace: Fix accounting of subop hashes")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
