On 01/17/2018 04:46 PM, Jens Axboe wrote: > On 1/17/18 5:34 AM, Ming Lei wrote: >> We know this WARN_ON is harmless and the stack trace isn't useful too, >> so convert it to printk(), and avoid to confuse people. > > I disagree, it is useful to know the exact path it happened from, > in case it's a valid warning. It could be an inline run and > we screwed up the logic, or it could be from a workqueue and > the reason would be entirely different. Then add a dump_stack or whatever, but WARN_ON does have fatal effects for some setups. If it can happen then WARN_ON is just wrong.