locking/lockdep: Improve noinstr vs errors

[ 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: 6eebad1ad3 ("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>
This commit is contained in:
Peter Zijlstra
2021-06-21 13:12:38 +02:00
committed by Sasha Levin
parent 59aa5c91f8
commit ca2acbd548
3 changed files with 6 additions and 2 deletions

View File

@@ -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;
}