[PATCH v17 27/47] locking/lockdep: prevent various lockdep assertions when lockdep_off()'ed
STALE309d
From: Byungchul Park <byungchul@sk.com>
Date: 2025-10-02 08:13:58
Also in:
dri-devel, linux-arch, linux-block, linux-doc, linux-ext4, linux-fsdevel, linux-i2c, linux-ide, linux-media, linux-mm, linux-nfs, linux-rt-devel, lkml, netdev, rcu
Subsystem:
locking primitives, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Will Deacon, Boqun Feng, Linus Torvalds
Revision v17 of 8 in this series.
Revisions (8)
lockdep provides APIs for assertion only if lockdep is enabled at the
moment asserting to avoid unnecessary confusion, using the following
condition, debug_locks && !this_cpu_read(lockdep_recursion).
However, lockdep_{off,on}() are also used for disabling and enabling
lockdep for a simular purpose. Add !lockdep_recursing(current) that is
updated by lockdep_{off,on}() to the condition so that the assertions
are aware of !__lockdep_enabled if lockdep_off()'ed.
Signed-off-by: Byungchul Park <byungchul@sk.com>
---
include/linux/lockdep.h | 3 ++-
kernel/locking/lockdep.c | 10 ++++++++++
2 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index ef03d8808c10..c83fe95199db 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h@@ -303,6 +303,7 @@ extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie); lockdep_assert_once(!current->lockdep_depth) #define lockdep_recursing(tsk) ((tsk)->lockdep_recursion) +extern bool lockdep_recursing_current(void); #define lockdep_pin_lock(l) lock_pin_lock(&(l)->dep_map) #define lockdep_repin_lock(l,c) lock_repin_lock(&(l)->dep_map, (c))
@@ -630,7 +631,7 @@ DECLARE_PER_CPU(int, hardirqs_enabled); DECLARE_PER_CPU(int, hardirq_context); DECLARE_PER_CPU(unsigned int, lockdep_recursion); -#define __lockdep_enabled (debug_locks && !this_cpu_read(lockdep_recursion)) +#define __lockdep_enabled (debug_locks && !this_cpu_read(lockdep_recursion) && !lockdep_recursing_current()) #define lockdep_assert_irqs_enabled() \ do { \
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index dc97f2753ef8..39b9e3e27c0b 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c@@ -6900,3 +6900,13 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s) warn_rcu_exit(rcu); } EXPORT_SYMBOL_GPL(lockdep_rcu_suspicious); + +/* + * For avoiding header dependency when using (struct task_struct *)current + * and lockdep_recursing() at the same time. + */ +noinstr bool lockdep_recursing_current(void) +{ + return lockdep_recursing(current); +} +EXPORT_SYMBOL_GPL(lockdep_recursing_current);
--
2.17.1