On Fri, 2009-11-27 at 16:03 +0100, Jiri Slaby wrote: > On 11/25/2009 01:47 AM, akpm@xxxxxxxxxxxxxxxxxxxx wrote: > > The mm-of-the-moment snapshot 2009-11-24-16-47 has been uploaded to > > Hi, when executing qemu-kvm I often get following warning and a hard lockup. > > WARNING: at kernel/smp.c:292 smp_call_function_single+0xbd/0x140() > Hardware name: To Be Filled By O.E.M. > Modules linked in: kvm_intel kvm fuse ath5k ath > Pid: 3265, comm: qemu-kvm Not tainted 2.6.32-rc8-mm1_64 #912 > Call Trace: > [<ffffffff81039678>] warn_slowpath_common+0x78/0xb0 > [<ffffffffa007fd50>] ? __vcpu_clear+0x0/0xd0 [kvm_intel] > [<ffffffff810396bf>] warn_slowpath_null+0xf/0x20 > [<ffffffff8106410d>] smp_call_function_single+0xbd/0x140 > [<ffffffffa0080af6>] vmx_vcpu_load+0x46/0x170 [kvm_intel] > [<ffffffffa004dd94>] kvm_arch_vcpu_load+0x24/0x60 [kvm] > [<ffffffffa0047a8d>] kvm_sched_in+0xd/0x10 [kvm] > [<ffffffff8102de37>] finish_task_switch+0x67/0xc0 > [<ffffffff814699f8>] schedule+0x2f8/0x9c0 > > It is a regression against 2009-11-13-19-59. > > Any ideas? Looks like kvm is trying to send an IPI from the preempt notifiers, which are called with IRQs disabled, not a sane thing to do. If they really want that, they'll have to use a pre-allocated struct call_single_data and use __smp_call_function_single. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
