From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: [Fwd: 2.6.22-rc1-mm1: strange GPF when panicing under kvm] Date: Thu, 17 May 2007 20:31:39 +0300 Message-ID: <464C917B.6050401@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Jeremy Fitzhardinge To: kvm-devel Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Copying kvm-devel - maybe someone here has an idea. A guest is faulting on the 'pause' instruction (aka 'rep nop'). -------- Original Message -------- Subject: 2.6.22-rc1-mm1: strange GPF when panicing under kvm Date: Wed, 16 May 2007 17:13:13 -0700 From: Jeremy Fitzhardinge To: Avi Kivity , Andi Kleen CC: Andrew Morton , Linux Kernel Mailing List When I boot 2.6.22-rc1-mm1 under kvm, but forget to specify a root filesystem, it panics as expected. However, when panicing, it gets a GPF in delay_tsc, and then starts recursively panicing. I don't really understand what's going on; the instruction it's faulting on seems to be "pause" (ie, rep;nop), which seems like it shouldn't fault at all. It looks like some kvm artifact to me, but I'm not sure. Hm, given the error code, maybe it's a segment register problem. VFS: Cannot open root device "" or unknown-block(254,0) Please append a correct "root=" boot option; here are the available partitions: 0300 4194304 hda driver: ide-disk 0301 4192933 hda1 Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(254,0) general protection fault: fffa [#1] PREEMPT SMP Modules linked in: CPU: 0 EIP: 0060:[] Not tainted VLI EFLAGS: 00000297 (2.6.22-rc1-mm1-paravirt #1391) EIP is at delay_tsc+0x20/0x42 eax: 00025431 ebx: 00000000 ecx: 00000000 edx: 00000002 esi: 55c34bd8 edi: 00000000 ebp: c1421e70 esp: c1421e5c ds: 007b es: 007b fs: 00d8 gs: 0000 ss: 0068 Process swapper (pid: 1, ti=c1420000 task=c141f4f0 task.ti=c1420000) Stack: 001c096b 55c0f7a7 00000000 00000003 00000000 c1421e80 c021dc90 00000001 00000000 c1421e90 c021dcb9 00000000 00000003 c1421ec0 c01298f3 c0426f0e c051bd60 c1421ec0 c012a168 c041f0a4 c1421ecc c0430656 c1421ecc c1421ef4 Call Trace: [] show_trace_log_lvl+0x1a/0x30 [] show_stack_log_lvl+0x9d/0xac [] show_registers+0x1f7/0x336 [] die+0x119/0x21b [] do_general_protection+0x1bf/0x1c7 [] error_code+0x72/0x78 [] __delay+0xc/0xe [] __const_udelay+0x27/0x29 [] panic+0xf8/0x101 [] mount_block_root+0x221/0x236 [] mount_root+0x59/0x5f [] prepare_namespace+0x102/0x149 [] kernel_init+0x2bf/0x2ce [] kernel_thread_helper+0x7/0x10 ======================= INFO: lockdep is turned off. Code: e2 8d 42 01 e8 cb ff ff ff c9 c3 55 89 e5 57 56 53 83 ec 08 89 45 ec 0f 31 8d 74 26 00 b9 00 00 00 00 89 c6 89 c8 09 f0 89 45 f0 90 0f 31 8d 74 26 00 b9 00 00 00 00 89 c6 89 c8 09 f0 2b 45 EIP: [] delay_tsc+0x20/0x42 SS:ESP 0068:c1421e5c general protection fault: fffa [#2] PREEMPT SMP Modules linked in: CPU: 0 EIP: 0060:[] Not tainted VLI EFLAGS: 00000282 (2.6.22-rc1-mm1-paravirt #1391) EIP is at _spin_unlock_irqrestore+0x44/0x6d eax: 00000282 ebx: c048cd80 ecx: c01096f7 edx: 00000001 esi: 00000282 edi: 00000068 ebp: c1421dbc esp: c1421db4 ds: 007b es: 007b fs: 00d8 gs: 0000 ss: 0068 Process swapper (pid: 1, ti=c1420000 task=c141f4f0 task.ti=c1420000) Stack: c1421e24 c1421e5c c1421dec c01096f7 c0420228 00000068 c1421e5c 00000001 c048ecd4 c1421e24 00000282 c1421e24 55c34bd8 fffffffa c1421e1c c037b992 fffffffa 0000000d 0000000b c011a748 00010000 c11c2000 c141f6c0 00000000 Call Trace: [] show_trace_log_lvl+0x1a/0x30 [] show_stack_log_lvl+0x9d/0xac [] show_registers+0x1f7/0x336 [] die+0x119/0x21b [] do_general_protection+0x1bf/0x1c7 [] error_code+0x72/0x78 [] die+0x188/0x21b [] do_general_protection+0x1bf/0x1c7 [] error_code+0x72/0x78 [] __delay+0xc/0xe [] __const_udelay+0x27/0x29 [] panic+0xf8/0x101 [] mount_block_root+0x221/0x236 [] mount_root+0x59/0x5f [] prepare_namespace+0x102/0x149 [] kernel_init+0x2bf/0x2ce [] kernel_thread_helper+0x7/0x10 ======================= INFO: lockdep is turned off. Code: 89 d8 e8 7a 4f ea ff f7 c6 00 02 00 00 75 13 89 f0 50 9d 90 8d b4 26 00 00 00 00 e8 0d 9f dc ff eb 11 e8 b0 b4 dc ff 89 f0 50 9d <90> 8d b4 26 00 00 00 00 b8 01 00 00 00 e8 c9 99 da ff 89 e0 25 EIP: [] _spin_unlock_irqrestore+0x44/0x6d SS:ESP 0068:c1421db4 general protection fault: fffa [#3] J -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/