From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: 2.6.29-rc1-wl gives WARNING on ich8lan Date: Thu, 15 Jan 2009 20:13:21 -0800 Message-ID: <20090115201321.12cedb23.akpm@linux-foundation.org> References: <20090114231546.GI1457@gamma.logic.tuwien.ac.at> <20090114222550.80fb1bb2.akpm@linux-foundation.org> <9929d2390901152006h3e47b2c8m3a63f741333b9c3c@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Norbert Preining , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, David Graham , Bruce Allan To: Jeff Kirsher Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:48392 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750937AbZAPEOC (ORCPT ); Thu, 15 Jan 2009 23:14:02 -0500 In-Reply-To: <9929d2390901152006h3e47b2c8m3a63f741333b9c3c@mail.gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 15 Jan 2009 20:06:17 -0800 Jeff Kirsher wrote: > On Wed, Jan 14, 2009 at 10:25 PM, Andrew Morton > wrote: > > On Thu, 15 Jan 2009 00:15:46 +0100 Norbert Preining wrote: > > > >> Hi all, > >> > >> (please cc) > > > > (please cc right lists!) > > > >> 2.6.29-rc1-wl (wireless testing) gives me: > >> > >> [ 367.804080] WARNING: at drivers/net/e1000e/ich8lan.c:412 e1000_acquire_swflag_ich8lan+0x35/0xcc() > >> [ 367.804085] Hardware name: VGN-Z11VN_B > >> [ 367.804088] e1000e mutex contention. Owned by pid 3781 > >> [ 367.804092] Modules linked in: binfmt_misc rfcomm l2cap kvm isofs zlib_inflate fuse dm_crypt dm_mod firewire_sbp2 loop arc4 iwlagn iwlcore rfkill joydev firewire_ohci mac80211 firewire_core crc_itu_t cfg80211 btusb sony_laptop tpm_infineon video backlight > >> [ 367.804143] Pid: 8, comm: events/1 Not tainted 2.6.29-rc1-wl #1 > >> [ 367.804148] Call Trace: > >> [ 367.804158] [] warn_slowpath+0xd8/0x112 > >> [ 367.804169] [] _spin_unlock_irqrestore+0x31/0x3d > >> [ 367.804178] [] try_to_wake_up+0x168/0x17a > >> [ 367.804186] [] default_wake_function+0x0/0x9 > >> [ 367.804196] [] delay_tsc+0x0/0xc8 > >> [ 367.804204] [] dequeue_entity+0xf/0x102 > >> [ 367.804211] [] e1000_acquire_swflag_ich8lan+0x35/0xcc > >> [ 367.804219] [] e1000e_read_phy_reg_bm+0x39/0xbe > >> [ 367.804227] [] e1000e_phy_has_link_generic+0x50/0xcc > >> [ 367.804234] [] dequeue_entity+0xf/0x102 > >> [ 367.804242] [] e1000_watchdog_task+0x0/0x6ef > >> [ 367.804249] [] e1000e_check_for_copper_link+0x24/0x86 > >> [ 367.804257] [] lock_timer_base+0x26/0x4b > >> [ 367.804265] [] e1000_has_link+0x40/0xc1 > >> [ 367.804272] [] e1000_watchdog_task+0x37/0x6ef > >> [ 367.804280] [] e1000_watchdog_task+0x0/0x6ef > >> [ 367.804289] [] run_workqueue+0x87/0x122 > >> [ 367.804296] [] worker_thread+0xd8/0xe7 > >> [ 367.804304] [] autoremove_wake_function+0x0/0x2e > >> [ 367.804311] [] worker_thread+0x0/0xe7 > >> [ 367.804318] [] worker_thread+0x0/0xe7 > >> [ 367.804324] [] kthread+0x47/0x73 > >> [ 367.804332] [] child_rip+0xa/0x20 > >> [ 367.804338] [] kthread+0x0/0x73 > >> [ 367.804344] [] child_rip+0x0/0x20 > >> [ 367.804349] ---[ end trace 608ec83548aefe5d ]--- > >> > >> Should I be concerned? > >> > > > > I don't think so. It looks like it's just some developer debug code: > > > > if (!mutex_trylock(&nvm_mutex)) { > > WARN(1, KERN_ERR "e1000e mutex contention. Owned by process " > > "%s (pid %d), required by process %s (pid %d)\n", > > nvm_owner_name, nvm_owner_pid, > > current->comm, current->pid); > > > > mutex_lock(&nvm_mutex); > > } > > > > guys, is this actually indicative of a bug? An unexpected state? > > > > If not, I'd suggest that this code simply be removed, or downgraded > > into a developer-only debug thing. We don't want the kernel to be > > spewing scary things at people. > > > > -- > > > > A message from Dave Graham ... > > The message identifies a condition that rarely occurs, and that I'd > like to monitor for a few more weeks. While this WARN occurred > fequently until recent 2.6.28 kernels, the messages have already > helped us to tighten our code to reduce contentious access to this > path, and so we now longer expect many. In fact at this time we only > have one (this one) report, out of a total 1,296 WARNs shown at > www.kerneloops.org for all 2.6.29-rc builds. There's been a minor > improvement to the WARN message tagged as tag v2.6.29-rc1-6-geefacf3, > and I'd like to collect & analyze a few reports that include that > change. > > I'll monitor reports up at keneloops daily, and when I've got 5 or > more, I can quickly move the WARN to debug-only code, so reports will > soon stop. Does that sound OK? OK, thanks, sounds good to me.