Commit-ID: 4bf508621855613ca2ac782f70c3171e0e8bb011 Gitweb: https://git.kernel.org/tip/4bf508621855613ca2ac782f70c3171e0e8bb011 Author: Bart Van Assche <bvanass...@acm.org> AuthorDate: Thu, 14 Feb 2019 15:00:52 -0800 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Thu, 28 Feb 2019 07:55:46 +0100
locking/lockdep: Verify whether lock objects are small enough to be used as class keys Signed-off-by: Bart Van Assche <bvanass...@acm.org> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Johannes Berg <johan...@sipsolutions.net> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Waiman Long <long...@redhat.com> Cc: Will Deacon <will.dea...@arm.com> Cc: johannes.b...@intel.com Cc: t...@kernel.org Link: https://lkml.kernel.org/r/20190214230058.196511-18-bvanass...@acm.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/locking/lockdep.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 630be9ac6253..84427441824e 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -758,6 +758,17 @@ static bool assign_lock_key(struct lockdep_map *lock) { unsigned long can_addr, addr = (unsigned long)lock; +#ifdef __KERNEL__ + /* + * lockdep_free_key_range() assumes that struct lock_class_key + * objects do not overlap. Since we use the address of lock + * objects as class key for static objects, check whether the + * size of lock_class_key objects does not exceed the size of + * the smallest lock object. + */ + BUILD_BUG_ON(sizeof(struct lock_class_key) > sizeof(raw_spinlock_t)); +#endif + if (__is_kernel_percpu_address(addr, &can_addr)) lock->key = (void *)can_addr; else if (__is_module_percpu_address(addr, &can_addr))
