From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pg0-f66.google.com ([74.125.83.66]:35881 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750923AbeFZEWN (ORCPT ); Tue, 26 Jun 2018 00:22:13 -0400 Date: Tue, 26 Jun 2018 13:22:08 +0900 From: Sergey Senozhatsky To: Steven Rostedt Cc: Sergey Senozhatsky , syzbot , linux-kernel@vger.kernel.org, pmladek@suse.com, sergey.senozhatsky@gmail.com, syzkaller-bugs@googlegroups.com, Samuel Ortiz , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: Re: INFO: rcu detected stall in vprintk_emit Message-ID: <20180626042208.GA31439@jagdpanzerIV> (sfid-20180626_062257_730863_1A0D7454) References: <000000000000720530056f7f9b63@google.com> <20180626014924.GB11229@jagdpanzerIV> <20180625225937.43aee76c@vmware.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20180625225937.43aee76c@vmware.local.home> Sender: linux-wireless-owner@vger.kernel.org List-ID: On (06/25/18 22:59), Steven Rostedt wrote: > > Or ratelimited error reporting and cond_resched() > > [that would be option B]: > > I don't think this is a printk() issue per se, so I think Option B is > the only option. You should not get stuck in an infinite loop if we run > short on memory. Perhaps we could have an Option C which would exit > this loop gracefully with some kind of error. But I haven't looked at > the surrounding code to be sure if that is possible. Agree. I like Option B - an endless loop is the root cause, at the same time filling up logbuf with useless data is useless. Can't tell if Option C is feasible, up to networking people. -ss