On Tue, Jan 31, 2017 at 10:58 AM, Johannes Thumshirn <jthumshirn@xxxxxxx> wrote: > > [...] > >> Please-please-please, let's not use WARN for something that is not a >> kernel bug and is user-triggerable. This makes it impossible to >> automate kernel testing and requires hiring an army of people doing >> mechanical job of sorting out WARNING reports into kernel-bugs and >> non-kernel-bugs. >> If the message is absolutely necessary (while kernel does not >> generally explain every EINVAL on console), the following will do: >> >> if (!blk_rq_nr_phys_segments(rq)) { >> pr_err("you are doing something wrong\n"); >> return -EINVAL; >> } > > Yes I understand that. OTOH having the WARN helps you finding the caller because > of to the stack trace. But arguably that could be accomplished with function > graph tracing as well. I'll re-send a v2 as a proper patch. Thank you very much. Stack trace can be done with dump_stack() if necessary, e.g. pr_err("you are doing something wrong here:\n"); dump_stack(); -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html