From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from galois.linutronix.de ([193.142.43.55]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nb2wJ-00BrVu-11 for linux-um@lists.infradead.org; Sun, 03 Apr 2022 16:18:56 +0000 From: Thomas Gleixner Subject: Re: UML time-travel warning from __run_timers In-Reply-To: <84f9d627092660c38400b607198c3b83f795be7f.camel@sipsolutions.net> References: <20220330110156.GA9250@axis.com> <84f9d627092660c38400b607198c3b83f795be7f.camel@sipsolutions.net> Date: Sun, 03 Apr 2022 18:18:51 +0200 Message-ID: <877d86m978.ffs@tglx> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: Johannes Berg , Vincent Whitchurch Cc: linux-um@lists.infradead.org, linux-kernel@vger.kernel.org, Anna-Maria Gleixner , Frederic Weisbecker On Sat, Apr 02 2022 at 16:09, Johannes Berg wrote: > At init, we get > > init_timer_cpu(0) base 0 clk=0xffff8ad0, next_expiry=0x13fff8acf > init_timer_cpu(0) base 1 clk=0xffff8ad0, next_expiry=0x13fff8acf > > which makes sense, jiffies is set up to wrap very quickly after boot. > > The warning triggers when we have jiffies=0x13fff9600, so it's just > after the "next_expiry", so in this code: which does not make sense. If next_expiry is 0x13fff8acf and jiffies advanced to 0x13fff9600 when the warning triggered, then either it missed to expire the timer at 0x13fff8acf or it failed to recalculate next_expiry. Could you enable all [hr]timer tracepoints on the kernel command line, set panic on warn and ftrace_dump_on_oops which should spill out the tracebuffer on the console and provide the output. That should at least give us an hint what's going on. Thanks, tglx _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um