On 12/9/18 9:58 AM, Guenter Roeck wrote: > On Sun, Dec 09, 2018 at 07:26:47AM -0700, Jens Axboe wrote: >> >> Ming that lockdep spews the following trace. What this essentially says >> is that the sbitmap swap_lock was used inconsistently in IRQ enabled >> and disabled context, and that is usually indicative of a bug that will >> cause a deadlock. >> >> For this case, it's a false positive. The swap_lock is used from process >> context only, when we swap the bits in the word and cleared mask. We >> also end up doing that when we are getting a driver tag, from the >> blk_mq_mark_tag_wait(), and from there we hold the waitqueue lock with >> IRQs disabled. However, this isn't from an actual IRQ, it's still >> process context. >> >> Mark the swap_lock as not needing validation to silence this warning. >> > > checkpatch says: > > $ scripts/checkpatch.pl jens2 > ERROR: lockdep_no_validate class is reserved for device->mutex. > #357: FILE: lib/sbitmap.c:68: > + lockdep_set_novalidate_class(&sb->map[i].swap_lock); > > ... which I think explains the warning I am seeing with this patch applied. Try the other patch I sent out earlier, that should work. -- Jens Axboe
