From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Thomason Subject: Re: Guest Hang Bugs Date: Thu, 15 Jan 2009 17:26:34 -0800 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Cc: To: James Thomason , Avi Kivity Return-path: Received: from multiply.divide.org ([207.218.248.89]:61234 "EHLO multiply.divide.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752788AbZAPB0k (ORCPT ); Thu, 15 Jan 2009 20:26:40 -0500 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: Avi and others, The system under load finally panicked and all cores hit 100%, so I spoke too soon. Unfortunately my console was garbled and I was not able to get the text of that panic. Afterwards I am unable to boot the guest with kvm -smp > 2 because the guest panics at boot time. The text of that boot time panic is below. However, booting the guest with kvm -smp 1 works. After rebooting the KVM host, I am able to boot the guest with kvm -smp 12 etc again. I will try to induce the guest to panic again and see if I can capture it. Configuration: KVM HOST: Ubuntu 8.10 KVM 83 2.6.29-rc1 KVM Guest: Ubuntu 8.10 2.6.27-9-server Text of Guest Boot Panic: Boot from (hd0,0) ext3 cd532b94-1a97-4337-bfe9-75e699839bab Starting up ... [ 3.290000] Stuck ?? [ 3.320000] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 [ 3.320000] IP: [] kmem_cache_create+0x7e/0x1a0 [ 3.320000] PGD 0 [ 3.320000] Oops: 0002 [1] SMP [ 3.320000] CPU 0 [ 3.320000] Modules linked in: [ 3.320000] Pid: 1, comm: swapper Tainted: G S 2.6.27-9-server #1 [ 3.320000] RIP: 0010:[] [] kmem_cache_create+0x7e/0x1a0 [ 3.320000] RSP: 0018:ffff88081cc7be50 EFLAGS: 00010293 [ 3.320000] RAX: 0000000000000080 RBX: ffffffff806df710 RCX: 0000000000000001 [ 3.320000] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 [ 3.320000] RBP: ffff88081cc7be90 R08: 0000000000000040 R09: ffffffff806e1e18 [ 3.320000] R10: ffff88081ccfdc00 R11: 0000000000000400 R12: 0000000000000080 [ 3.320000] R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff805f9c69 [ 3.320000] FS: 0000000000000000(0000) GS:ffffffff806e1a80(0000) knlGS:0000000000000000 [ 3.320000] CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b [ 3.320000] CR2: 0000000000000018 CR3: 0000000000201000 CR4: 00000000000006e0 [ 3.320000] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3.320000] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 3.320000] Process swapper (pid: 1, threadinfo ffff88081cc7a000, task ffff88081cc80000) [ 3.320000] Stack: ffffffff80743eb2 0000000000000000 0000000000042000 ffffffff80784848 [ 3.320000] ffffffff807449ac 0000000000000000 0000000000093360 0000000000000000 [ 3.320000] ffff88081cc7bea0 ffffffff80744a09 ffff88081cc7bf10 ffffffff8020a041 [ 3.320000] Call Trace: [ 3.320000] [] ? init_pipe_fs+0x0/0x56 [ 3.320000] [] ? eventpoll_init+0x0/0x8a [ 3.320000] [] eventpoll_init+0x5d/0x8a [ 3.320000] [] do_one_initcall+0x41/0x170 [ 3.320000] [] ? register_irq_proc+0x19/0xf0 [ 3.320000] [] ? load_elf_binary+0xc70/0x11c0 [ 3.320000] [] kernel_init+0xd2/0x128 [ 3.320000] [] ? schedule_tail+0x27/0x70 [ 3.320000] [] child_rip+0xa/0x11 [ 3.320000] [] ? kernel_init+0x0/0x128 [ 3.320000] [] ? child_rip+0x0/0x11 [ 3.320000] [ 3.320000] [ 3.320000] Code: 83 40 7c 01 8b 40 0c bf ff ff ff ff 44 39 e0 41 0f 4e c4 89 43 0c eb 16 0f 1f 44 00 00 48 63 c7 48 8b 94 c3 f0 02 00 00 8b 43 0c <89> 42 18 48 c7 c6 18 1e 6e 80 e8 b3 ed 0b 00 83 f8 3f 89 c7 7e [ 3.320000] RIP [] kmem_cache_create+0x7e/0x1a0 [ 3.320000] RSP [ 3.320000] CR2: 0000000000000018 [ 3.320000] ---[ end trace 4eaa2a86a8e2da22 ]--- [ 3.320000] Kernel panic - not syncing: Attempted to kill init!