From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: BUG: using smp_processor_id() in preemptible [00000000] code: pm-suspend/17334 Date: Wed, 04 Jun 2008 12:41:29 +0300 Message-ID: <48466349.1030907@qumranet.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Zdenek Kabelac , linux-kernel@vger.kernel.org, kvm@vger.kernel.org To: Jiri Kosina Return-path: Received: from bzq-179-150-194.static.bezeqint.net ([212.179.150.194]:27774 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758395AbYFDJla (ORCPT ); Wed, 4 Jun 2008 05:41:30 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: Jiri Kosina wrote: > [ re-introduced LKML to CC, and also added KVM CCs] > > On Tue, 3 Jun 2008, Zdenek Kabelac wrote: > > >> 2008/6/3 Jiri Kosina : >> >>> On Tue, 3 Jun 2008, Zdenek Kabelac wrote: >>> >>> >>>> Another backtrace from suspend code path: >>>> (T61, 2GB, C2D, no SD card) >>>> kernel from git 20080603, commit 1beee8dc8cf58e3f605bd7b34d7a39939be7d8d2 >>>> ---- >>>> agpgart-intel 0000:00:00.0: LATE suspend >>>> platform bay.0: LATE suspend >>>> platform dock.0: LATE suspend >>>> Extended CMOS year: 2000 >>>> hwsleep-0324 [00] enter_sleep_state : Entering sleep state [S3] >>>> Back to C! >>>> BUG: using smp_processor_id() in preemptible [00000000] code: pm-suspend/17334 >>>> caller is do_machine_check+0xa9/0x500 >>>> Pid: 17334, comm: pm-suspend Not tainted 2.6.26-rc4 #31 >>>> Call Trace: >>>> [] debug_smp_processor_id+0xcc/0xd0 >>>> [] do_machine_check+0xa9/0x500 >>>> [] ? init_8259A+0x1b/0x120 >>>> [] mce_init+0x56/0xf0 >>>> [] mce_resume+0xb/0x10 >>>> [] __sysdev_resume+0x20/0x60 >>>> [] sysdev_resume+0x58/0x90 >>>> [] device_power_up+0x9/0x10 >>>> [] suspend_devices_and_enter+0x147/0x1a0 >>>> [] enter_state+0x146/0x1d0 >>>> [] state_store+0xba/0x100 >>>> [] kobj_attr_store+0x17/0x20 >>>> [] sysfs_write_file+0xca/0x140 >>>> [] vfs_write+0xcb/0x190 >>>> [] sys_write+0x50/0x90 >>>> [] system_call_after_swapgs+0x7b/0x80 >>>> >>> This looks very much like the oops you reported here: >>> http://lkml.org/lkml/2008/4/7/130 >>> >>> Is this also a virtual machine run under KVM, as it has been in the >>> aforementioned thread? >>> >> Ahh yes - you are right , I've completely forget about that old post - >> I've thought that my post are usually getting fixed sooner :) >> So yes - this is actually the same bug which is still not fixed within >> the latest kernel - the machine is running qemu guest (which seems to >> me now somehow also slower) >> > > OK, so it looks like KVM could be wrongly enabling IRQs/preemption on the > resume path. The original bug-report is on > http://lkml.org/lkml/2008/4/7/130 > > Wait, is this in a virtual machine, or on a host that's also running a virtual machine (or has the kvm modules loaded)? I looked at the kvm host resume path, and it doesn't touch interrupts. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic.