From: Peter Zijlstra peterz@infradead.org
[ Upstream commit 49faa77759b211fff344898edc23bb780707fff5 ]
Better handle the failure paths.
vmlinux.o: warning: objtool: debug_locks_off()+0x23: call to console_verbose() leaves .noinstr.text section vmlinux.o: warning: objtool: debug_locks_off()+0x19: call to __kasan_check_write() leaves .noinstr.text section
debug_locks_off+0x19/0x40: instrument_atomic_write at include/linux/instrumented.h:86 (inlined by) __debug_locks_off at include/linux/debug_locks.h:17 (inlined by) debug_locks_off at lib/debug_locks.c:41
Fixes: 6eebad1ad303 ("lockdep: __always_inline more for noinstr") Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Signed-off-by: Ingo Molnar mingo@kernel.org Link: https://lore.kernel.org/r/20210621120120.784404944@infradead.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/debug_locks.h | 2 ++ kernel/locking/lockdep.c | 4 +++- lib/debug_locks.c | 2 +- 3 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h index 2915f56ad421..edb5c186b0b7 100644 --- a/include/linux/debug_locks.h +++ b/include/linux/debug_locks.h @@ -27,8 +27,10 @@ extern int debug_locks_off(void); int __ret = 0; \ \ if (!oops_in_progress && unlikely(c)) { \ + instrumentation_begin(); \ if (debug_locks_off() && !debug_locks_silent) \ WARN(1, "DEBUG_LOCKS_WARN_ON(%s)", #c); \ + instrumentation_end(); \ __ret = 1; \ } \ __ret; \ diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 858b96b438ce..cdca007551e7 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -842,7 +842,7 @@ static int count_matching_names(struct lock_class *new_class) }
/* used from NMI context -- must be lockless */ -static __always_inline struct lock_class * +static noinstr struct lock_class * look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass) { struct lockdep_subclass_key *key; @@ -850,12 +850,14 @@ look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass) struct lock_class *class;
if (unlikely(subclass >= MAX_LOCKDEP_SUBCLASSES)) { + instrumentation_begin(); debug_locks_off(); printk(KERN_ERR "BUG: looking up invalid subclass: %u\n", subclass); printk(KERN_ERR "turning off the locking correctness validator.\n"); dump_stack(); + instrumentation_end(); return NULL; }
diff --git a/lib/debug_locks.c b/lib/debug_locks.c index 06d3135bd184..a75ee30b77cb 100644 --- a/lib/debug_locks.c +++ b/lib/debug_locks.c @@ -36,7 +36,7 @@ EXPORT_SYMBOL_GPL(debug_locks_silent); /* * Generic 'turn off all lock debugging' function: */ -noinstr int debug_locks_off(void) +int debug_locks_off(void) { if (debug_locks && __debug_locks_off()) { if (!debug_locks_silent) {