Hello I use kernel 2.6.8 (standard Debian kernel 2.6.8-1-k7) and LVM 2.0. On a logical volume of the size 100 GiB, I freezed the xfs filesystem and tried to make a snapshot with lvcreate which segfaulted and wrote into syslog: # pvcreate /dev/hda8 # vgcreate vg00 /dev/hda8 # lvcreate -L100G -nlv00 vg00 # mkfs.xfs /dev/vg00/lv00 (mount and put document tree on it) # lvcreate -L 5G -c 1024k -s -n snapshot0 /dev/vg00/lv00 (lvcreate did not like the reserved word snapshot...) # lvcreate -L 5G -c 1024k -s -n snap0 /dev/vg00/lv00 gives me: Oct 14 22:57:26 stingray kernel: ------------[ cut here ]------------ Oct 14 22:57:26 stingray kernel: kernel BUG at drivers/md/dm-io.c:148! Oct 14 22:57:26 stingray kernel: invalid operand: 0000 [#1] Oct 14 22:57:26 stingray kernel: PREEMPT Oct 14 22:57:26 stingray kernel: Modules linked in: dm_snapshot ipv6 uhci_hcd pci_hotplug via_agp agpgart parport_pc parport floppy evdev pcspkr ehci_hcd usbcore via_ircc irda crc_ccitt xfs capability commoncap dm_mod via_rhine mii crc32 rtc ext3 j bd mbcache ide_generic via82cxxx ide_disk ide_core unix font vesafb cfbcopyarea cfbimgblt cfbfillrect Oct 14 22:57:26 stingray kernel: CPU: 0 Oct 14 22:57:26 stingray kernel: EIP: 0060: [__crc_pm_idle+775153/5541136] Not tainted Oct 14 22:57:26 stingray kernel: EFLAGS: 00010202 (2.6.8-1-k7) Oct 14 22:57:26 stingray kernel: EIP is at bio_set_alloc+0x80/0x150 [dm_mod] Oct 14 22:57:26 stingray kernel: eax: f71de800 ebx: 00000102 ecx: f761ede0 edx: f71cf000 Oct 14 22:57:26 stingray kernel: esi: f71de800 edi: f89d5780 ebp: 00000000 esp: f7189db4 Oct 14 22:57:26 stingray kernel: ds: 007b es: 007b ss: 0068 Oct 14 22:57:26 stingray kernel: Process lvcreate (pid: 1913, threadinfo=f7188000 task=f7431710) Oct 14 22:57:26 stingray kernel: Stack: f71de800 00000010 00000000 00000010 00000004 00000800 00000000 00000000 Oct 14 22:57:26 stingray kernel: f7189e98 f89cd8da f89d5780 00000010 00000102 f7189e48 00000000 00000010 Oct 14 22:57:26 stingray kernel: 00000001 f7189e98 00000000 00000000 00000010 f89cda7f 00000010 00000000 Oct 14 22:57:26 stingray kernel: Call Trace: Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+776795/5541136] do_region+0x4a/0x130 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+777216/5541136] dispatch_io+0xbf/0xd0 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+776577/5541136] vm_get_page+0x0/0x40 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+776641/5541136] vm_next_page+0x0/0x20 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+777332/5541136] sync_io+0x63/0xf0 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+777940/5541136] dm_io_sync_vm+0x43/0x50 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+776577/5541136] vm_get_page+0x0/0x40 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+776641/5541136] vm_next_page+0x0/0x20 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+2285106/5541136] chunk_io+0x61/0x70 [dm_snapshot] Oct 14 22:57:26 stingray kernel: [bdget+65/272] bdget+0x41/0x110 Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+2285356/5541136] read_header+0x2b/0x90 [dm_snapshot] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+2286291/5541136] persistent_read_metadata+0x22/0xc0 [dm_snapshot] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+2282487/5541136] snapshot_resume+0x26/0x60 [dm_snapshot] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+762079/5541136] dm_table_resume_targets+0x3e/0x50 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+756150/5541136] dm_resume+0x75/0xd0 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+769993/5541136] do_resume+0x128/0x190 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+773675/5541136] ctl_ioctl+0xea/0x150 [dm_mod] Oct 14 22:57:26 stingray kernel: [__crc_pm_idle+770097/5541136] dev_suspend+0x0/0x20 [dm_mod] Oct 14 22:57:26 stingray kernel: [sys_ioctl+269/656] sys_ioctl+0x10d/0x290 Oct 14 22:57:26 stingray kernel: [syscall_call+7/11] syscall_call+0x7/0xb Oct 14 22:57:26 stingray kernel: Code: 0f 0b 94 00 22 ef 9c f8 c7 44 24 10 00 00 00 00 8b 44 24 10 After the segmentation fault, the /var partition (which is located on the LV) could not be reached: all reads and writes to/from it blocked until the machine got rebooted. I thought you might be interested. I wanted to check the list archives but lists.sistina.com did not answer. Salut Mark _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
