On Thu, Jun 11, 2020 at 10:44:17AM +0800, Ming Lei wrote: > BDI is unregistered from del_gendisk() which is usually done in device's > release handler from device hotplug or error handling context, so BDI > can be unregistered anytime. True. > It should be normal for __mark_inode_dirty to see un-registered BDI, > so replace the WARN() with pr_debug() just for debug purpose. I'd kill it entirely while we're at it..