linux-toradex.git/kernel/trace/rv/rv.c, branch v6.15

rv: Fix out-of-bound memory access in rv_is_container_monitor()

2025-04-12T16:13:30+00:00

When rv_is_container_monitor() is called on the last monitor in
rv_monitors_list, KASAN yells:

  BUG: KASAN: global-out-of-bounds in rv_is_container_monitor+0x101/0x110
  Read of size 8 at addr ffffffff97c7c798 by task setup/221

  The buggy address belongs to the variable:
   rv_monitors_list+0x18/0x40

This is due to list_next_entry() is called on the last entry in the list.
It wraps around to the first list_head, and the first list_head is not
embedded in struct rv_monitor_def.

Fix it by checking if the monitor is last in the list.

Cc: stable@vger.kernel.org
Cc: Gabriele Monaco 
Fixes: cb85c660fcd4 ("rv: Add option for nested monitors and include sched")
Link: https://lore.kernel.org/e85b5eeb7228bfc23b8d7d4ab5411472c54ae91b.1744355018.git.namcao@linutronix.de
Signed-off-by: Nam Cao 
Signed-off-by: Steven Rostedt (Google)

rv: Fix missing unlock on double nested monitors return path

2025-04-02T13:51:26+00:00

RV doesn't support nested monitors having children monitors themselves
and exits with the EINVAL code. However, it returns without unlocking
the rv_interface_lock.

Unlock the lock before returning from the initialisation function.

Cc: Masami Hiramatsu 
Link: https://lore.kernel.org/20250402071351.19864-2-gmonaco@redhat.com
Fixes: cb85c660fcd4 ("rv: Add option for nested monitors and include sched")
Reported-by: kernel test robot 
Reported-by: Julia Lawall 
Closes: https://lore.kernel.org/r/202503310200.UBXGitB4-lkp@intel.com
Signed-off-by: Gabriele Monaco 
Signed-off-by: Steven Rostedt (Google)

rv: Add option for nested monitors and include sched

2025-03-24T21:27:39+00:00

Monitors describing complex systems, such as the scheduler, can easily
grow to the point where they are just hard to understand because of the
many possible state transitions.
Often it is possible to break such descriptions into smaller monitors,
sharing some or all events. Enabling those smaller monitors concurrently
is, in fact, testing the system as if we had one single larger monitor.
Splitting models into multiple specification is not only easier to
understand, but gives some more clues when we see errors.

Add the possibility to create container monitors, whose only purpose is
to host other nested monitors. Enabling a container monitor enables all
nested ones, but it's still possible to enable nested monitors
independently.
Add the sched monitor as first container, for now empty.

Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Juri Lelli 
Link: https://lore.kernel.org/20250305140406.350227-3-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco 
Signed-off-by: Steven Rostedt (Google)

rv: Simplify manual steps in monitor creation

2024-12-27T19:20:03+00:00

While creating a new monitor in RV, besides generating code from dot2k,
there are a few manual steps which can be tedious and error prone, like
adding the tracepoints, makefile lines and kconfig.

This patch restructures the existing monitors to keep some files in the
monitor's folder itself, which can be automatically generated by future
versions of dot2k.

Monitors have now their own Kconfig and tracepoint snippets. For
simplicity, the main tracepoint definition, is moved to the RV
directory, it defines only the tracepoint classes and includes the
monitor-specific tracepoints, which reside in the monitor directory.

Tracepoints and Kconfig no longer need to be copied and adapted from
existing ones but only need to be included in the main files.
The Makefile remains untouched since there's little advantage in having
a separated Makefile for each monitor with a single line and including
it in the main RV Makefile.

Cc: Juri Lelli 
Cc: Thomas Gleixner 
Cc: John Kacur 
Link: https://lore.kernel.org/20241227144752.362911-6-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco 
Signed-off-by: Steven Rostedt (Google)

rv: Fix a typo

2024-10-04T23:09:23+00:00

Fix a typo in comments.

Cc: Masami Hiramatsu 
Cc: Mathieu Desnoyers 
Link: https://lore.kernel.org/20240911114349.20449-1-algonell@gmail.com
Reported-by: Matthew Wilcox 
Signed-off-by: Andrew Kreimer 
Signed-off-by: Steven Rostedt (Google)

[tree-wide] finally take no_llseek out

2024-09-27T15:18:43+00:00

no_llseek had been defined to NULL two years ago, in commit 868941b14441
("fs: remove no_llseek")

To quote that commit,

  At -rc1 we'll need do a mechanical removal of no_llseek -

  git grep -l -w no_llseek | grep -v porting.rst | while read i; do
	sed -i '/\/d' $i
  done

  would do it.

Unfortunately, that hadn't been done.  Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
	.llseek = no_llseek,
so it's obviously safe.

Signed-off-by: Al Viro 
Signed-off-by: Linus Torvalds

rv: Update rv_en(dis)able_monitor doc to match kernel-doc

2024-05-21T23:03:35+00:00

The patch updates the function documentation comment for
rv_en(dis)able_monitor to adhere to the kernel-doc specification.

Link: https://lore.kernel.org/linux-trace-kernel/20240520054239.61784-1-yang.lee@linux.alibaba.com

Fixes: 102227b970a15 ("rv: Add Runtime Verification (RV) interface")
Signed-off-by: Yang Li 
Signed-off-by: Steven Rostedt (Google)

rv: Remove redundant assignment to variable retval

2023-04-25T23:24:28+00:00

Variable retval is being assigned a value that is never read, it is
being re-assigned a new value in both paths of a following if statement.
Remove the assignment.

Cleans up clang-scan warning:
kernel/trace/rv/rv.c:293:2: warning: Value stored to 'retval' is never read [deadcode.DeadStores]
        retval = count;

Link: https://lkml.kernel.org/r/20230418150018.3123753-1-colin.i.king@gmail.com

Cc: Masami Hiramatsu 
Signed-off-by: Colin Ian King 
Acked-by: Daniel Bristot de Oliveira 
Signed-off-by: Steven Rostedt (Google)

rv: remove redundant initialization of pointer ptr

2023-01-25T15:31:02+00:00

The pointer ptr is being initialized with a value that is never read,
it is being updated later on a call to strim. Remove the extraneous
initialization.

Link: https://lkml.kernel.org/r/20230116161612.77192-1-colin.i.king@gmail.com

Cc: Daniel Bristot de Oliveira 
Cc: Masami Hiramatsu 
Signed-off-by: Colin Ian King 
Signed-off-by: Steven Rostedt (Google)

Documentation/rv: Add a basic documentation

2022-07-30T18:01:29+00:00

Add the runtime-verification.rst document, explaining the basics of RV
and how to use the interface.

Link: https://lkml.kernel.org/r/4be7d1a88ab1e2eb0767521e1ab52a149a154bc4.1659052063.git.bristot@kernel.org

Cc: Wim Van Sebroeck 
Cc: Guenter Roeck 
Cc: Jonathan Corbet 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: Peter Zijlstra 
Cc: Will Deacon 
Cc: Catalin Marinas 
Cc: Marco Elver 
Cc: Dmitry Vyukov 
Cc: "Paul E. McKenney" 
Cc: Shuah Khan 
Cc: Gabriele Paoloni 
Cc: Juri Lelli 
Cc: Clark Williams 
Cc: Tao Zhou 
Cc: Randy Dunlap 
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira 
Signed-off-by: Steven Rostedt (Google)