Commit Graph

48433 Commits

Author SHA1 Message Date
Gabriele Monaco
e8440a88e5 rv: Add nrp and sssw per-task monitors
Add 2 per-task monitors as part of the sched model:

* nrp: need-resched preempts
    Monitor to ensure preemption requires need resched.
* sssw: set state sleep and wakeup
    Monitor to ensure sched_set_state to sleepable leads to sleeping and
    sleeping tasks require wakeup.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20250728135022.255578-9-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Acked-by: Nam Cao <namcao@linutronix.de>
Tested-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Gabriele Monaco
d0096c2f9c rv: Replace tss and sncid monitors with more complete sts
The tss monitor currently guarantees task switches can happen only while
scheduling, whereas the sncid monitor enforces scheduling occurs with
interrupt disabled.

Replace the monitors with a more comprehensive specification which
implies both but also ensures that:
* each scheduler call disable interrupts to switch
* each task switch happens with interrupts disabled

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nam Cao <namcao@linutronix.de>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20250728135022.255578-8-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Gabriele Monaco
adcc3bfa88 sched: Adapt sched tracepoints for RV task model
Add the following tracepoint:
* sched_set_need_resched(tsk, cpu, tif)
    Called when a task is set the need resched [lazy] flag

Remove the unused ip parameter from sched_entry and sched_exit and alter
sched_entry to have a value of preempt consistent with the one used in
sched_switch.

Also adapt all monitors using sched_{entry,exit} to avoid breaking build.

These tracepoints are useful to describe the Linux task model and are
adapted from the patches by Daniel Bristot de Oliveira
(https://bristot.me/linux-task-model/).

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nam Cao <namcao@linutronix.de>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250728135022.255578-7-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Gabriele Monaco
9d475d80c9 rv: Retry when da monitor detects race conditions
DA monitor can be accessed from multiple cores simultaneously, this is
likely, for instance when dealing with per-task monitors reacting on
events that do not always occur on the CPU where the task is running.
This can cause race conditions where two events change the next state
and we see inconsistent values. E.g.:

  [62] event_srs: 27: sleepable x sched_wakeup -> running (final)
  [63] event_srs: 27: sleepable x sched_set_state_sleepable -> sleepable
  [63] error_srs: 27: event sched_switch_suspend not expected in the state running

In this case the monitor fails because the event on CPU 62 wins against
the one on CPU 63, although the correct state should have been
sleepable, since the task get suspended.

Detect if the current state was modified by using try_cmpxchg while
storing the next value. If it was, try again reading the current state.
After a maximum number of failed retries, react by calling a special
tracepoint, print on the console and reset the monitor.

Remove the functions da_monitor_curr_state() and da_monitor_set_state()
as they only hide the underlying implementation in this case.

Monitors where this type of condition can occur must be able to account
for racing events in any possible order, as we cannot know the winner.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20250728135022.255578-6-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Gabriele Monaco
79de661707 rv: Adjust monitor dependencies
RV monitors relying on the preemptirqs tracepoints are set as dependent
on PREEMPT_TRACER and IRQSOFF_TRACER. In fact, those configurations do
enable the tracepoints but are not the minimal configurations enabling
them, which are TRACE_PREEMPT_TOGGLE and TRACE_IRQFLAGS (not selectable
manually).

Set TRACE_PREEMPT_TOGGLE and TRACE_IRQFLAGS as dependencies for
monitors.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250728135022.255578-5-gmonaco@redhat.com
Fixes: fbe6c09b7e ("rv: Add scpd, snep and sncid per-cpu monitors")
Acked-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Gabriele Monaco
7f904ff6e5 rv: Use strings in da monitors tracepoints
Using DA monitors tracepoints with KASAN enabled triggers the following
warning:

 BUG: KASAN: global-out-of-bounds in do_trace_event_raw_event_event_da_monitor+0xd6/0x1a0
 Read of size 32 at addr ffffffffaada8980 by task ...
 Call Trace:
  <TASK>
 [...]
  do_trace_event_raw_event_event_da_monitor+0xd6/0x1a0
  ? __pfx_do_trace_event_raw_event_event_da_monitor+0x10/0x10
  ? trace_event_sncid+0x83/0x200
  trace_event_sncid+0x163/0x200
 [...]
 The buggy address belongs to the variable:
  automaton_snep+0x4e0/0x5e0

This is caused by the tracepoints reading 32 bytes __array instead of
__string from the automata definition. Such strings are literals and
reading 32 bytes ends up in out of bound memory accesses (e.g. the next
automaton's data in this case).
The error is harmless as, while printing the string, we stop at the null
terminator, but it should still be fixed.

Use the __string facilities while defining the tracepoints to avoid
reading out of bound memory.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250728135022.255578-4-gmonaco@redhat.com
Fixes: 792575348f ("rv/include: Add deterministic automata monitor definition via C macros")
Reviewed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Gabriele Monaco
7b70ac4cad rv: Remove trailing whitespace from tracepoint string
RV event tracepoints print a line with the format:
    "event_xyz: S0 x event -> S1 "
    "event_xyz: S1 x event -> S0 (final)"

While printing an event leading to a non-final state, the line
has a trailing white space (visible above before the closing ").

Adapt the format string not to print the trailing whitespace if we are
not printing "(final)".

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250728135022.255578-3-gmonaco@redhat.com
Reviewed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Nam Cao
3cfb9c1a7d rv: Fix wrong type cast in reactors_show() and monitor_reactor_show()
Argument 'p' of reactors_show() and monitor_reactor_show() is not a pointer
to struct rv_reactor, it is actually a pointer to the list_head inside
struct rv_reactor. Therefore it's wrong to cast 'p' to struct rv_reactor *.

This wrong type cast has been there since the beginning. But it still
worked because the list_head was the first field in struct rv_reactor_def.
This is no longer true since commit 3d3c376118 ("rv: Merge struct
rv_reactor_def into struct rv_reactor") moved the list_head, and this wrong
type cast became a functional problem.

Properly use container_of() instead.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/b4febbd6844311209e4c8768b65d508b81bd8c9b.1753625621.git.namcao@linutronix.de
Fixes: 3d3c376118 ("rv: Merge struct rv_reactor_def into struct rv_reactor")
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 10:39:34 -04:00
Nam Cao
e82aea50fe rv: Fix wrong type cast in monitors_show()
Argument 'p' of monitors_show() is not a pointer to struct rv_monitor, it
is actually a pointer to the list_head inside struct rv_monitor. Therefore
it is wrong to cast 'p' to struct rv_monitor *.

This wrong type cast has been there since the beginning. But it still
worked because the list_head was the first field in struct rv_monitor_def.
This is no longer true since commit 24cbfe18d5 ("rv: Merge struct
rv_monitor_def into struct rv_monitor") moved the list_head, and this wrong
type cast became a functional problem.

Properly use container_of() instead.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/35e49e97696007919ceacf73796487a2e15a3d02.1753625621.git.namcao@linutronix.de
Fixes: 24cbfe18d5 ("rv: Merge struct rv_monitor_def into struct rv_monitor")
Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 10:39:34 -04:00
Nam Cao
b8a7fba39c rv: Remove struct rv_monitor::reacting
The field 'reacting' in struct rv_monitor is set but never used. Delete it.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/a6c16f845d2f1a09c4d0934ab83f3cb14478a71d.1753378331.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-25 09:04:14 -04:00
Nam Cao
3d3800b4f7 rv: Remove rv_reactor's reference counter
rv_reactor has a reference counter to ensure it is not removed while
monitors are still using it.

However, this is futile, as __exit functions are not expected to fail and
will proceed normally despite rv_unregister_reactor() returning an error.

At the moment, reactors do not support being built as modules, therefore
they are never removed and the reference counters are not necessary.

If we support building RV reactors as modules in the future, kernel
module's centralized facilities such as try_module_get(), module_put() or
MODULE_SOFTDEP should be used instead of this custom implementation.

Remove this reference counter.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/bb946398436a5e17fb0f5b842ef3313c02291852.1753378331.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-25 09:04:14 -04:00
Nam Cao
3d3c376118 rv: Merge struct rv_reactor_def into struct rv_reactor
Each struct rv_reactor has a unique struct rv_reactor_def associated with
it. struct rv_reactor is statically allocated, while struct rv_reactor_def
is dynamically allocated.

This makes the code more complicated than it should be:

  - Lookup is required to get the associated rv_reactor_def from rv_reactor

  - Dynamic memory allocation is required for rv_reactor_def. This is
    harder to get right compared to static memory. For instance, there is
    an existing mistake: rv_unregister_reactor() does not free the memory
    allocated by rv_register_reactor(). This is fortunately not a real
    memory leak problem as rv_unregister_reactor() is never called.

Simplify and merge rv_reactor_def into rv_reactor.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/71cb91c86cd40df5b8c492b788787f2a73c3eaa3.1753378331.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-25 09:04:14 -04:00
Nam Cao
24cbfe18d5 rv: Merge struct rv_monitor_def into struct rv_monitor
Each struct rv_monitor has a unique struct rv_monitor_def associated with
it. struct rv_monitor is statically allocated, while struct rv_monitor_def
is dynamically allocated.

This makes the code more complicated than it should be:

  - Lookup is required to get the associated rv_monitor_def from rv_monitor

  - Dynamic memory allocation is required for rv_monitor_def. This is
    harder to get right compared to static memory. For instance, there is
    an existing mistake: rv_unregister_monitor() does not free the memory
    allocated by rv_register_monitor(). This is fortunately not a real
    memory leak problem, as rv_unregister_monitor() is never called.

Simplify and merge rv_monitor_def into rv_monitor.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/194449c00f87945c207aab4c96920c75796a4f53.1753378331.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-25 09:04:14 -04:00
Nam Cao
b0c08dd534 rv: Remove unused field in struct rv_monitor_def
rv_monitor_def::task_monitor is not used. Delete it.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/502d94f2696435690a2b1fdbe80a9e56c96fcabf.1753378331.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-25 09:04:13 -04:00
Gabriele Monaco
58d5f0d437 rv: Return init error when registering monitors
Monitors generated with dot2k have their registration function (the one
called during monitor initialisation) return always 0, even if the
registration failed on RV side.
This can hide potential errors.

Return the value returned by the RV register function.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250723161240.194860-6-gmonaco@redhat.com
Reviewed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-24 10:43:46 -04:00
Gabriele Monaco
560473f2e2 verification/rvgen: Organise Kconfig entries for nested monitors
The current behaviour of rvgen when running with the -a option is to
append the necessary lines at the end of the configuration for Kconfig,
Makefile and tracepoints.
This is not always the desired behaviour in case of nested monitors:
while tracepoints are not affected by nesting and the Makefile's only
requirement is that the parent monitor is built before its children, in
the Kconfig it is better to have children defined right after their
parent, otherwise the result has wrong indentation:

[*]   foo_parent monitor
[*]     foo_child1 monitor
[*]     foo_child2 monitor
[*]   bar_parent monitor
[*]     bar_child1 monitor
[*]     bar_child2 monitor
[*]   foo_child3 monitor
[*]   foo_child4 monitor

Adapt rvgen to look for a different marker for nested monitors in the
Kconfig file and append the line right after the last sibling, instead
of the last monitor.
Also add the marker when creating a new parent monitor.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250723161240.194860-5-gmonaco@redhat.com
Reviewed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-24 10:43:46 -04:00
Gabriele Monaco
9efcf59082 tools/dot2c: Fix generated files going over 100 column limit
The dot2c.py script generates all states in a single line. This breaks the
100 column limit when the state machines are non-trivial.

Change dot2c.py to generate the states in separate lines in case the
generated line is going to be too long.

Also adapt existing monitors with line length over the limit.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250723161240.194860-4-gmonaco@redhat.com
Suggested-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-24 10:43:46 -04:00
Nam Cao
9a425da913 panic: Fix up description of vpanic()
The description above vpanic() has the wrong function name. Fix it up.

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/23a7e8add6546b155371b7e0fbb37bb1def13d6e.1752232374.git.namcao@linutronix.de
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/lkml/20250711183802.2d8c124d@canb.auug.org.au/
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-11 14:25:39 -04:00
Nam Cao
fac5493251 rv: Allow to configure the number of per-task monitor
Now that there are 2 monitors for real-time applications, users may want to
enable both of them simultaneously. Make the number of per-task monitor
configurable. Default it to 2 for now.

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/93e83313fc4ba7f6e66f4abe80ca5f5494d658d0.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:02 -04:00
Nam Cao
f74f8bb246 rv: Add rtapp_sleep monitor
Add a monitor for checking that real-time tasks do not go to sleep in a
manner that may cause undesirable latency.

Also change
	RV depends on TRACING
to
	RV select TRACING
to avoid the following recursive dependency:

 error: recursive dependency detected!
	symbol TRACING is selected by PREEMPTIRQ_TRACEPOINTS
	symbol PREEMPTIRQ_TRACEPOINTS depends on TRACE_IRQFLAGS
	symbol TRACE_IRQFLAGS is selected by RV_MON_SLEEP
	symbol RV_MON_SLEEP depends on RV
	symbol RV depends on TRACING

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/75bc5bcc741d153aa279c95faf778dff35c5c8ad.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:01 -04:00
Nam Cao
9162620eb6 rv: Add rtapp_pagefault monitor
Userspace real-time applications may have design flaws that they raise
page faults in real-time threads, and thus have unexpected latencies.

Add an linear temporal logic monitor to detect this scenario.

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/78fea8a2de6d058241d3c6502c1a92910772b0ed.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:01 -04:00
Nam Cao
886fc86e94 rv: Add rtapp container monitor
Add the container "rtapp" which is the monitor collection for detecting
problems with real-time applications. The monitors will be added in the
follow-up commits.

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/fb18b87631d386271de00959d8d4826f23fcd1cd.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:01 -04:00
Nam Cao
a9769a5b98 rv: Add support for LTL monitors
While attempting to implement DA monitors for some complex specifications,
deterministic automaton is found to be inappropriate as the specification
language. The automaton is complicated, hard to understand, and
error-prone.

For these cases, linear temporal logic is more suitable as the
specification language.

Add support for linear temporal logic runtime verification monitor.

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/d366c1fed60ed4e8f6451f3c15a99755f2740b5f.1752088709.git.namcao@linutronix.de
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:01 -04:00
Nam Cao
c94d27c01b rv: rename CONFIG_DA_MON_EVENTS to CONFIG_RV_MON_EVENTS
CONFIG_DA_MON_EVENTS is not specific to deterministic automaton. It could
be used for other monitor types. Therefore rename it to
CONFIG_RV_MON_EVENTS.

This prepares for the introduction of linear temporal logic monitor.

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/507210517123d887c1d208aa2fd45ec69765d3f0.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:01 -04:00
Nam Cao
ff4e233d8a rv: Let the reactors take care of buffers
Each RV monitor has one static buffer to send to the reactors. If multiple
errors are detected simultaneously, the one buffer could be overwritten.

Instead, leave it to the reactors to handle buffering.

Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:00 -04:00
Nam Cao
3f045de7f5 panic: Add vpanic()
vpanic() is useful for implementing runtime verification reactors. Add it.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:00 -04:00
Nam Cao
0af3ecdde5 printk: Make vprintk_deferred() public
vprintk_deferred() is useful for implementing runtime verification
reactors. Make it public.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:00 -04:00
Nam Cao
2d08876263 rv: Add #undef TRACE_INCLUDE_FILE
Without "#undef TRACE_INCLUDE_FILE", there could be a build error due to
TRACE_INCLUDE_FILE being redefined. Therefore add it.

Also fix a typo while at it.

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/f805e074581e927bb176c742c981fa7675b6ebe5.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:00 -04:00
Linus Torvalds
772b78c2ab Merge tag 'sched_urgent_for_v6.16_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Borislav Petkov:

 - Fix the calculation of the deadline server task's runtime as this
   mishap was preventing realtime tasks from running

 - Avoid a race condition during migrate-swapping two tasks

 - Fix the string reported for the "none" dynamic preemption option

* tag 'sched_urgent_for_v6.16_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Fix dl_server runtime calculation formula
  sched/core: Fix migrate_swap() vs. hotplug
  sched: Fix preemption string of preempt_dynamic_none
2025-07-06 11:17:47 -07:00
Linus Torvalds
a1639ce5e5 Merge tag 'perf_urgent_for_v6.16_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:

 - Revert uprobes to using CAP_SYS_ADMIN again as currently they can
   destructively modify kernel code from an unprivileged process

 - Move a warning to where it belongs

* tag 'perf_urgent_for_v6.16_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Revert to requiring CAP_SYS_ADMIN for uprobes
  perf/core: Fix the WARN_ON_ONCE is out of lock protected region
2025-07-06 10:49:27 -07:00
Rafael J. Wysocki
250d0579da Merge branch 'pm-sleep'
Merge fixes related to system sleep for 6.16-rc5:

 - Fix typo in the ABI documentation (Sumanth Gavini).

 - Allow swap to be used a bit longer during system suspend and
   hibernation to avoid suspend failures under memory pressure (Mario
   Limonciello).

* pm-sleep:
  PM: sleep: docs: Replace "diasble" with "disable"
  PM: Restrict swap use to later in the suspend sequence
2025-07-04 21:54:55 +02:00
kuyo chang
fc975cfb36 sched/deadline: Fix dl_server runtime calculation formula
In our testing with 6.12 based kernel on a big.LITTLE system, we were
seeing instances of RT tasks being blocked from running on the LITTLE
cpus for multiple seconds of time, apparently by the dl_server. This
far exceeds the default configured 50ms per second runtime.

This is due to the fair dl_server runtime calculation being scaled
for frequency & capacity of the cpu.

Consider the following case under a Big.LITTLE architecture:
Assume the runtime is: 50,000,000 ns, and Frequency/capacity
scale-invariance defined as below:
Frequency scale-invariance: 100
Capacity scale-invariance: 50
First by Frequency scale-invariance,
the runtime is scaled to 50,000,000 * 100 >> 10 = 4,882,812
Then by capacity scale-invariance,
it is further scaled to 4,882,812 * 50 >> 10 = 238,418.
So it will scaled to 238,418 ns.

This smaller "accounted runtime" value is what ends up being
subtracted against the fair-server's runtime for the current period.
Thus after 50ms of real time, we've only accounted ~238us against the
fair servers runtime. This 209:1 ratio in this example means that on
the smaller cpu the fair server is allowed to continue running,
blocking RT tasks, for over 10 seconds before it exhausts its supposed
50ms of runtime.  And on other hardware configurations it can be even
worse.

For the fair deadline_server, to prevent realtime tasks from being
unexpectedly delayed, we really do want to use fixed time, and not
scaled time for smaller capacity/frequency cpus. So remove the scaling
from the fair server's accounting to fix this.

Fixes: a110a81c52 ("sched/deadline: Deferrable dl server")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: John Stultz <jstultz@google.com>
Signed-off-by: kuyo chang <kuyo.chang@mediatek.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Acked-by: John Stultz <jstultz@google.com>
Tested-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/r/20250702021440.2594736-1-kuyo.chang@mediatek.com
2025-07-04 10:35:56 +02:00
Peter Zijlstra
ba677dbe77 perf: Revert to requiring CAP_SYS_ADMIN for uprobes
Jann reports that uprobes can be used destructively when used in the
middle of an instruction. The kernel only verifies there is a valid
instruction at the requested offset, but due to variable instruction
length cannot determine if this is an instruction as seen by the
intended execution stream.

Additionally, Mark Rutland notes that on architectures that mix data
in the text segment (like arm64), a similar things can be done if the
data word is 'mistaken' for an instruction.

As such, require CAP_SYS_ADMIN for uprobes.

Fixes: c9e0924e5c ("perf/core: open access to probes for CAP_PERFMON privileged process")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/CAG48ez1n4520sq0XrWYDHKiKxE_+WCfAK+qt9qkY4ZiBGmL-5g@mail.gmail.com
2025-07-03 10:33:55 +02:00
Peter Zijlstra
009836b4fa sched/core: Fix migrate_swap() vs. hotplug
On Mon, Jun 02, 2025 at 03:22:13PM +0800, Kuyo Chang wrote:

> So, the potential race scenario is:
>
> 	CPU0							CPU1
> 	// doing migrate_swap(cpu0/cpu1)
> 	stop_two_cpus()
> 							  ...
> 							 // doing _cpu_down()
> 							      sched_cpu_deactivate()
> 								set_cpu_active(cpu, false);
> 								balance_push_set(cpu, true);
> 	cpu_stop_queue_two_works
> 	    __cpu_stop_queue_work(stopper1,...);
> 	    __cpu_stop_queue_work(stopper2,..);
> 	stop_cpus_in_progress -> true
> 		preempt_enable();
> 								...
> 							1st balance_push
> 							stop_one_cpu_nowait
> 							cpu_stop_queue_work
> 							__cpu_stop_queue_work
> 							list_add_tail  -> 1st add push_work
> 							wake_up_q(&wakeq);  -> "wakeq is empty.
> 										This implies that the stopper is at wakeq@migrate_swap."
> 	preempt_disable
> 	wake_up_q(&wakeq);
> 	        wake_up_process // wakeup migrate/0
> 		    try_to_wake_up
> 		        ttwu_queue
> 		            ttwu_queue_cond ->meet below case
> 		                if (cpu == smp_processor_id())
> 			         return false;
> 			ttwu_do_activate
> 			//migrate/0 wakeup done
> 		wake_up_process // wakeup migrate/1
> 	           try_to_wake_up
> 		    ttwu_queue
> 			ttwu_queue_cond
> 		        ttwu_queue_wakelist
> 			__ttwu_queue_wakelist
> 			__smp_call_single_queue
> 	preempt_enable();
>
> 							2nd balance_push
> 							stop_one_cpu_nowait
> 							cpu_stop_queue_work
> 							__cpu_stop_queue_work
> 							list_add_tail  -> 2nd add push_work, so the double list add is detected
> 							...
> 							...
> 							cpu1 get ipi, do sched_ttwu_pending, wakeup migrate/1
>

So this balance_push() is part of schedule(), and schedule() is supposed
to switch to stopper task, but because of this race condition, stopper
task is stuck in WAKING state and not actually visible to be picked.

Therefore CPU1 can do another schedule() and end up doing another
balance_push() even though the last one hasn't been done yet.

This is a confluence of fail, where both wake_q and ttwu_wakelist can
cause crucial wakeups to be delayed, resulting in the malfunction of
balance_push.

Since there is only a single stopper thread to be woken, the wake_q
doesn't really add anything here, and can be removed in favour of
direct wakeups of the stopper thread.

Then add a clause to ttwu_queue_cond() to ensure the stopper threads
are never queued / delayed.

Of all 3 moving parts, the last addition was the balance_push()
machinery, so pick that as the point the bug was introduced.

Fixes: 2558aacff8 ("sched/hotplug: Ensure only per-cpu kthreads run during hotplug")
Reported-by: Kuyo Chang <kuyo.chang@mediatek.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Kuyo Chang <kuyo.chang@mediatek.com>
Link: https://lkml.kernel.org/r/20250605100009.GO39944@noisy.programming.kicks-ass.net
2025-07-01 15:02:03 +02:00
Thomas Weißschuh
3ebb1b6522 sched: Fix preemption string of preempt_dynamic_none
Zero is a valid value for "preempt_dynamic_mode", namely
"preempt_dynamic_none".

Fix the off-by-one in preempt_model_str(), so that "preempty_dynamic_none"
is correctly formatted as PREEMPT(none) instead of PREEMPT(undef).

Fixes: 8bdc5daaa0 ("sched: Add a generic function to return the preemption string")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20250626-preempt-str-none-v2-1-526213b70a89@linutronix.de
2025-07-01 15:02:02 +02:00
Luo Gengkun
7b4c5a3754 perf/core: Fix the WARN_ON_ONCE is out of lock protected region
commit 3172fb9866 ("perf/core: Fix WARN in perf_cgroup_switch()") try to
fix a concurrency problem between perf_cgroup_switch and
perf_cgroup_event_disable. But it does not to move the WARN_ON_ONCE into
lock-protected region, so the warning is still be triggered.

Fixes: 3172fb9866 ("perf/core: Fix WARN in perf_cgroup_switch()")
Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20250626135403.2454105-1-luogengkun@huaweicloud.com
2025-06-30 09:32:49 +02:00
Linus Torvalds
2fc18d0b89 Merge tag 'perf_urgent_for_v6.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fix from Borislav Petkov:

 - Make sure an AUX perf event is really disabled when it overruns

* tag 'perf_urgent_for_v6.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/aux: Fix pending disable flow when the AUX ring buffer overruns
2025-06-29 08:16:02 -07:00
Linus Torvalds
ded779017a Merge tag 'trace-v6.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fix from Steven Rostedt:

 - Fix possible UAF on error path in filter_free_subsystem_filters()

   When freeing a subsystem filter, the filter for the subsystem is
   passed in to be freed and all the events within the subsystem will
   have their filter freed too. In order to free without waiting for RCU
   synchronization, list items are allocated to hold what is going to be
   freed to free it via a call_rcu(). If the allocation of these items
   fails, it will call the synchronization directly and free after that
   (causing a bit of delay for the user).

   The subsystem filter is first added to this list and then the filters
   for all the events under the subsystem. The bug is if one of the
   allocations of the list items for the event filters fail to allocate,
   it jumps to the "free_now" label which will free the subsystem
   filter, then all the items on the allocated list, and then the event
   filters that were not added to the list yet. But because the
   subsystem filter was added first, it gets freed twice.

   The solution is to add the subsystem filter after the events, and
   then if any of the allocations fail it will not try to free any of
   them twice

* tag 'trace-v6.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Fix filter logic error
2025-06-28 11:39:24 -07:00
Linus Torvalds
0fd39af24e Merge tag 'mm-hotfixes-stable-2025-06-27-16-56' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
 "16 hotfixes.

  6 are cc:stable and the remainder address post-6.15 issues or aren't
  considered necessary for -stable kernels. 5 are for MM"

* tag 'mm-hotfixes-stable-2025-06-27-16-56' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  MAINTAINERS: add Lorenzo as THP co-maintainer
  mailmap: update Duje Mihanović's email address
  selftests/mm: fix validate_addr() helper
  crashdump: add CONFIG_KEYS dependency
  mailmap: correct name for a historical account of Zijun Hu
  mailmap: add entries for Zijun Hu
  fuse: fix runtime warning on truncate_folio_batch_exceptionals()
  scripts/gdb: fix dentry_name() lookup
  mm/damon/sysfs-schemes: free old damon_sysfs_scheme_filter->memcg_path on write
  mm/alloc_tag: fix the kmemleak false positive issue in the allocation of the percpu variable tag->counters
  lib/group_cpus: fix NULL pointer dereference from group_cpus_evenly()
  mm/hugetlb: remove unnecessary holding of hugetlb_lock
  MAINTAINERS: add missing files to mm page alloc section
  MAINTAINERS: add tree entry to mm init block
  mm: add OOM killer maintainer structure
  fs/proc/task_mmu: fix PAGE_IS_PFNZERO detection for the huge zero folio
2025-06-27 20:34:10 -07:00
Edward Adam Davis
6921d1e07c tracing: Fix filter logic error
If the processing of the tr->events loop fails, the filter that has been
added to filter_head will be released twice in free_filter_list(&head->rcu)
and __free_filter(filter).

After adding the filter of tr->events, add the filter to the filter_head
process to avoid triggering uaf.

Link: https://lore.kernel.org/tencent_4EF87A626D702F816CD0951CE956EC32CD0A@qq.com
Fixes: a9d0aab5eb ("tracing: Fix regression of filter waiting a long time on RCU synchronization")
Reported-by: syzbot+daba72c4af9915e9c894@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=daba72c4af9915e9c894
Tested-by: syzbot+daba72c4af9915e9c894@syzkaller.appspotmail.com
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-06-27 15:51:36 -04:00
Mario Limonciello
12ffc3b151 PM: Restrict swap use to later in the suspend sequence
Currently swap is restricted before drivers have had a chance to do
their prepare() PM callbacks. Restricting swap this early means that if
a driver needs to evict some content from memory into sawp in it's
prepare callback, it won't be able to.

On AMD dGPUs this can lead to failed suspends under memory pressure
situations as all VRAM must be evicted to system memory or swap.

Move the swap restriction to right after all devices have had a chance
to do the prepare() callback.  If there is any problem with the sequence,
restore swap in the appropriate dpm resume callbacks or error handling
paths.

Closes: https://github.com/ROCm/ROCK-Kernel-Driver/issues/174
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/2362
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Nat Wittstock <nat@fardog.io>
Tested-by: Lucian Langa <lucilanga@7pot.org>
Link: https://patch.msgid.link/20250613214413.4127087-1-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-06-26 20:39:34 +02:00
Leo Yan
1476b21832 perf/aux: Fix pending disable flow when the AUX ring buffer overruns
If an AUX event overruns, the event core layer intends to disable the
event by setting the 'pending_disable' flag. Unfortunately, the event
is not actually disabled afterwards.

In commit:

  ca6c21327c ("perf: Fix missing SIGTRAPs")

the 'pending_disable' flag was changed to a boolean. However, the
AUX event code was not updated accordingly. The flag ends up holding a
CPU number. If this number is zero, the flag is taken as false and the
IRQ work is never triggered.

Later, with commit:

  2b84def990 ("perf: Split __perf_pending_irq() out of perf_pending_irq()")

a new IRQ work 'pending_disable_irq' was introduced to handle event
disabling. The AUX event path was not updated to kick off the work queue.

To fix this bug, when an AUX ring buffer overrun is detected, call
perf_event_disable_inatomic() to initiate the pending disable flow.

Also update the outdated comment for setting the flag, to reflect the
boolean values (0 or 1).

Fixes: 2b84def990 ("perf: Split __perf_pending_irq() out of perf_pending_irq()")
Fixes: ca6c21327c ("perf: Fix missing SIGTRAPs")
Signed-off-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: James Clark <james.clark@linaro.org>
Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Liang Kan <kan.liang@linux.intel.com>
Cc: Marco Elver <elver@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-perf-users@vger.kernel.org
Link: https://lore.kernel.org/r/20250625170737.2918295-1-leo.yan@arm.com
2025-06-26 10:50:37 +02:00
Linus Torvalds
ee88bddf7f Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Alexei Starovoitov:

 - Fix use-after-free in libbpf when map is resized (Adin Scannell)

 - Fix verifier assumptions about 2nd argument of bpf_sysctl_get_name
   (Jerome Marchand)

 - Fix verifier assumption of nullness of d_inode in dentry (Song Liu)

 - Fix global starvation of LRU map (Willem de Bruijn)

 - Fix potential NULL dereference in btf_dump__free (Yuan Chen)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: adapt one more case in test_lru_map to the new target_free
  libbpf: Fix possible use-after-free for externs
  selftests/bpf: Convert test_sysctl to prog_tests
  bpf: Specify access type of bpf_sysctl_get_name args
  libbpf: Fix null pointer dereference in btf_dump__free on allocation failure
  bpf: Adjust free target to avoid global starvation of LRU map
  bpf: Mark dentry->d_inode as trusted_or_null
2025-06-25 21:09:02 -07:00
Linus Torvalds
c5c2a8b497 Merge tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull mount fixes from Al Viro:
 "Several mount-related fixes"

* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  userns and mnt_idmap leak in open_tree_attr(2)
  attach_recursive_mnt(): do not lock the covering tree when sliding something under it
  replace collect_mounts()/drop_collected_mounts() with a safer variant
2025-06-25 20:48:48 -07:00
Arnd Bergmann
b6f5e74858 crashdump: add CONFIG_KEYS dependency
The dm_crypt code fails to build without CONFIG_KEYS:

kernel/crash_dump_dm_crypt.c: In function 'restore_dm_crypt_keys_to_thread_keyring':
kernel/crash_dump_dm_crypt.c:105:9: error: unknown type name 'key_ref_t'; did you mean 'key_ref_put'?

There is a mix of 'select KEYS' and 'depends on KEYS' in Kconfig,
so there is no single obvious solution here, but generally using 'depends on'
makes more sense and is less likely to cause dependency loops.

Link: https://lkml.kernel.org/r/20250620112140.3396316-1-arnd@kernel.org
Fixes: 62f17d9df6 ("crash_dump: retrieve dm crypt keys in kdump kernel")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Coiby Xu <coxu@redhat.com>
Cc: Dave Vasilevsky <dave@vasilevsky.ca>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-06-25 15:55:04 -07:00
Jerome Marchand
2eb7648558 bpf: Specify access type of bpf_sysctl_get_name args
The second argument of bpf_sysctl_get_name() helper is a pointer to a
buffer that is being written to. However that isn't specify in the
prototype.

Until commit 37cce22dbd ("bpf: verifier: Refactor helper access
type tracking"), all helper accesses were considered as a possible
write access by the verifier, so no big harm was done. However, since
then, the verifier might make wrong asssumption about the content of
that address which might lead it to make faulty optimizations (such as
removing code that was wrongly labeled dead). This is what happens in
test_sysctl selftest to the tests related to sysctl_get_name.

Add MEM_WRITE flag the second argument of bpf_sysctl_get_name().

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250619140603.148942-2-jmarchan@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-06-23 21:50:44 -07:00
Al Viro
7484e15dbb replace collect_mounts()/drop_collected_mounts() with a safer variant
collect_mounts() has several problems - one can't iterate over the results
directly, so it has to be done with callback passed to iterate_mounts();
it has an oopsable race with d_invalidate(); it creates temporary clones
of mounts invisibly for sync umount (IOW, you can have non-lazy umount
succeed leaving filesystem not mounted anywhere and yet still busy).

A saner approach is to give caller an array of struct path that would pin
every mount in a subtree, without cloning any mounts.

        * collect_mounts()/drop_collected_mounts()/iterate_mounts() is gone
        * collect_paths(where, preallocated, size) gives either ERR_PTR(-E...) or
a pointer to array of struct path, one for each chunk of tree visible under
'where' (i.e. the first element is a copy of where, followed by (mount,root)
for everything mounted under it - the same set collect_mounts() would give).
Unlike collect_mounts(), the mounts are *not* cloned - we just get pinning
references to the roots of subtrees in the caller's namespace.
        Array is terminated by {NULL, NULL} struct path.  If it fits into
preallocated array (on-stack, normally), that's where it goes; otherwise
it's allocated by kmalloc_array().  Passing 0 as size means that 'preallocated'
is ignored (and expected to be NULL).
        * drop_collected_paths(paths, preallocated) is given the array returned
by an earlier call of collect_paths() and the preallocated array passed to that
call.  All mount/dentry references are dropped and array is kfree'd if it's not
equal to 'preallocated'.
        * instead of iterate_mounts(), users should just iterate over array
of struct path - nothing exotic is needed for that.  Existing users (all in
audit_tree.c) are converted.

[folded a fix for braino reported by Venkat Rao Bagalkote <venkat88@linux.ibm.com>]

Fixes: 80b5dce8c5 ("vfs: Add a function to lazily unmount all mounts from any dentry")
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-06-23 14:01:49 -04:00
Linus Torvalds
c06944560a Merge tag 'mm-hotfixes-stable-2025-06-22-18-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
 "20 hotfixes. 7 are cc:stable and the remainder address post-6.15
  issues or aren't considered necessary for -stable kernels. Only 4 are
  for MM.

   - The series `Revert "bcache: update min_heap_callbacks to use
     default builtin swap"' from Kuan-Wei Chiu backs out the author's
     recent min_heap changes due to a performance regression.

     A fix for this regression has been developed but we felt it best to
     go back to the known-good version to give the new code more bake
     time.

   - A lot of MAINTAINERS maintenance.

     I like to get these changes upstreamed promptly because they can't
     break things and more accurate/complete MAINTAINERS info hopefully
     improves the speed and accuracy of our responses to submitters and
     reporters"

* tag 'mm-hotfixes-stable-2025-06-22-18-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  MAINTAINERS: add additional mmap-related files to mmap section
  MAINTAINERS: add memfd, shmem quota files to shmem section
  MAINTAINERS: add stray rmap file to mm rmap section
  MAINTAINERS: add hugetlb_cgroup.c to hugetlb section
  MAINTAINERS: add further init files to mm init block
  MAINTAINERS: update maintainers for HugeTLB
  maple_tree: fix MA_STATE_PREALLOC flag in mas_preallocate()
  MAINTAINERS: add missing test files to mm gup section
  MAINTAINERS: add missing mm/workingset.c file to mm reclaim section
  selftests/mm: skip uprobe vma merge test if uprobes are not enabled
  bcache: remove unnecessary select MIN_HEAP
  Revert "bcache: remove heap-related macros and switch to generic min_heap"
  Revert "bcache: update min_heap_callbacks to use default builtin swap"
  selftests/mm: add configs to fix testcase failure
  kho: initialize tail pages for higher order folios properly
  MAINTAINERS: add linux-mm@ list to Kexec Handover
  mm: userfaultfd: fix race of userfaultfd_move and swap cache
  mm/gup: revert "mm: gup: fix infinite loop within __get_longterm_locked"
  selftests/mm: increase timeout from 180 to 900 seconds
  mm/shmem, swap: fix softlockup with mTHP swapin
2025-06-23 09:20:39 -07:00
Linus Torvalds
33efa7dbab Merge tag 'irq_urgent_for_v6.16_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Borislav Petkov:

 - Fix missing prototypes warnings

 - Properly initialize work context when allocating it

 - Remove a method tracking when managed interrupts are suspended during
   hotplug, in favor of the code using a IRQ disable depth tracking now,
   and have interrupts get properly enabled again on restore

 - Make sure multiple CPUs getting hotplugged don't cause wrong tracking
   of the managed IRQ disable depth

* tag 'irq_urgent_for_v6.16_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/ath79-misc: Fix missing prototypes warnings
  genirq/irq_sim: Initialize work context pointers properly
  genirq/cpuhotplug: Restore affinity even for suspended IRQ
  genirq/cpuhotplug: Rebalance managed interrupts across multi-CPU hotplug
2025-06-22 10:17:51 -07:00
Linus Torvalds
17ef32ae66 Merge tag 'perf_urgent_for_v6.16_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:

 - Avoid a crash on a heterogeneous machine where not all cores support
   the same hw events features

 - Avoid a deadlock when throttling events

 - Document the perf event states more

 - Make sure a number of perf paths switching off or rescheduling events
   call perf_cgroup_event_disable()

 - Make sure perf does task sampling before its userspace mapping is
   torn down, and not after

* tag 'perf_urgent_for_v6.16_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Fix crash in icl_update_topdown_event()
  perf: Fix the throttle error of some clock events
  perf: Add comment to enum perf_event_state
  perf/core: Fix WARN in perf_cgroup_switch()
  perf: Fix dangling cgroup pointer in cpuctx
  perf: Fix cgroup state vs ERROR
  perf: Fix sample vs do_exit()
2025-06-22 10:11:45 -07:00