diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-03-15 03:07:54 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-03-15 03:07:54 +0300 |
commit | 29db00c252c7d0e015f3b436647b6f87d5854833 (patch) | |
tree | 62cbe636e5d2ca14a69abcfd46a86670d27442f7 /include/linux | |
parent | ed38ff164fba98a21993c95d240013f32309ccab (diff) | |
parent | c2679254b9c9980d9045f0f722cf093a2b1f7590 (diff) | |
download | linux-29db00c252c7d0e015f3b436647b6f87d5854833.tar.xz |
Merge tag 'trace-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Do not allow histogram values to have modifies. They can cause a NULL
pointer dereference if they do.
- Warn if hist_field_name() is passed a NULL. Prevent the NULL pointer
dereference mentioned above.
- Fix invalid address look up race in lookup_rec()
- Define ftrace_stub_graph conditionally to prevent linker errors
- Always check if RCU is watching at all tracepoint locations
* tag 'trace-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Make tracepoint lockdep check actually test something
ftrace,kcfi: Define ftrace_stub_graph conditionally
ftrace: Fix invalid address access in lookup_rec() when index is 0
tracing: Check field value in hist_field_name()
tracing: Do not let histogram values have some modifiers
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/tracepoint.h | 15 |
1 files changed, 6 insertions, 9 deletions
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index e299f29375bb..6811e43c1b5c 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -242,12 +242,11 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) * not add unwanted padding between the beginning of the section and the * structure. Force alignment to the same alignment as the section start. * - * When lockdep is enabled, we make sure to always do the RCU portions of - * the tracepoint code, regardless of whether tracing is on. However, - * don't check if the condition is false, due to interaction with idle - * instrumentation. This lets us find RCU issues triggered with tracepoints - * even when this tracepoint is off. This code has no purpose other than - * poking RCU a bit. + * When lockdep is enabled, we make sure to always test if RCU is + * "watching" regardless if the tracepoint is enabled or not. Tracepoints + * require RCU to be active, and it should always warn at the tracepoint + * site if it is not watching, as it will need to be active when the + * tracepoint is enabled. */ #define __DECLARE_TRACE(name, proto, args, cond, data_proto) \ extern int __traceiter_##name(data_proto); \ @@ -260,9 +259,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) TP_ARGS(args), \ TP_CONDITION(cond), 0); \ if (IS_ENABLED(CONFIG_LOCKDEP) && (cond)) { \ - rcu_read_lock_sched_notrace(); \ - rcu_dereference_sched(__tracepoint_##name.funcs);\ - rcu_read_unlock_sched_notrace(); \ + WARN_ON_ONCE(!rcu_is_watching()); \ } \ } \ __DECLARE_TRACE_RCU(name, PARAMS(proto), PARAMS(args), \ |