Alex, could you run that through ksymoops to get a backtrace ? Regards, Heinz -- The LVM Guy -- On Fri, Jun 18, 2004 at 05:33:00PM +0100, Alex Owen wrote: > Hello, > This morning I had an oops which I think is due to extending a > LVM1 LVsnapshot. > > I'm running a custom compiled 2.4.26 kernel. Debian source + LVM1.0.8 + > VFS-Lock from dm tarball. > > If anyone can give me any pointers to informantion of debuging such > problems that would be great! > > Thanks in advance for any advice on debugging. > > > Here is the syslog output: > Jun 18 07:39:02 falcon /USR/SBIN/CRON[3094]: (root) CMD ([ -x /usr/local/sbin/cron.snapshotextend ] && /usr/local/sbin/cron.snapshotextend) > Jun 18 07:39:03 falcon kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000000 > Jun 18 07:39:03 falcon kernel: printing eip: > Jun 18 07:39:03 falcon kernel: f8855b17 > Jun 18 07:39:03 falcon kernel: *pde = 1236b001 > Jun 18 07:39:03 falcon kernel: *pte = 00000000 > Jun 18 07:39:03 falcon kernel: Oops: 0000 > Jun 18 07:39:03 falcon kernel: CPU: 3 > Jun 18 07:39:03 falcon kernel: EIP: 0010:[ide-cd:__insmod_ide-cd_O/lib/modules/2.4.26-686-smp-lvm-vfslock/ke+-2135273/96] Tainted: P > Jun 18 07:39:03 falcon kernel: EFLAGS: 00010202 > Jun 18 07:39:03 falcon kernel: eax: 00000000 ebx: f8ac3260 ecx: 00000000 edx: 00000000 > Jun 18 07:39:03 falcon kernel: esi: 00402400 edi: f724aa00 ebp: 00006804 esp: c43d7dd0 > Jun 18 07:39:03 falcon kernel: ds: 0018 es: 0018 ss: 0018 > Jun 18 07:39:03 falcon kernel: Process kupdated (pid: 9, stackpage=c43d7000) > Jun 18 07:39:03 falcon kernel: Stack: f724aa00 f724ab70 f7c92970 00200000 00000080 00000002 00000000 00000000 > Jun 18 07:39:03 falcon kernel: f88526d1 c43d7e2e c43d7e30 00402380 f724aa00 00003a02 eda084a0 00000080 > Jun 18 07:39:03 falcon kernel: 00200000 c7d80f80 000c00b0 f7c92800 f7c89000 00402380 00000000 68040000 > Jun 18 07:39:03 falcon kernel: Call Trace: [ide-cd:__insmod_ide-cd_O/lib/modules/2.4.26-686-smp-lvm-vfslock/ke+-2148655/96] > [ide-cd:__insmod_ide-cd_O/lib/modules/2.4.26-686-smp-lvm-vfslock/ke+-2148425/96] [generic_make_request+288/304] [submit_bh+86/224] > [write_locked_buffers+32/44] > Jun 18 07:39:03 falcon kernel: [write_some_buffers+278/364] [sync_old_buffers+101/168] [kupdate+329/384] [ret_from_fork+6/32] [kupdate+0/384] > [arch_kernel_thread+40/56] > Jun 18 07:39:03 falcon kernel: > Jun 18 07:39:03 falcon kernel: Code: 8b 01 39 d9 74 37 39 71 08 75 ef 66 39 69 0c 75 e9 83 7c 24 > > The cron job I suspect of trigering the kernel bug is > /usr/local/sbin/cron.snapshotextend : > > ---8<--- > #!/bin/bash > ################################################# > # script to extend snapshots before they fill up! > ################################################# > > > #for lv in /dev/vg00/SNAP* ; do > for lv in $( ls /dev/vg00/SNAP* 2>/dev/null ) ; do > /sbin/lvdisplay $lv | grep "Allocated to snapshot" | \ > ( read junk junk junk LVpercent LVvalues > #make integer percentage > LVpercent=${LVpercent%\%} > LVpercent=${LVpercent%.*} > #get usage and size from values > LVusage=${LVvalues%%/*]} > LVusage=${LVusage#[} > LVsize=${LVvalues##[*/} > LVsize=${LVsize%]} > > #echo lv $lv > #echo percent $LVpercent > #echo used $LVusage > #echo size $LVsize > > if /usr/bin/expr $LVpercent '>=' 80 >/dev/null ; then > > LVsizeunit=${LVsize##* } > LVsizeunit=${LVsizeunit%B} > #calc 20% of existing snapshot size > LVextension=${LVsize%% *} > LVextension=${LVextension%.*} > LVextension=$(( $LVextension * 20 / 100 )) > > echo /sbin/lvextend -L+$LVextension$LVsizeunit $lv > /sbin/lvextend -L+${LVextension}${LVsizeunit} $lv > echo DONE > fi > > ) > > done > ---8<--- > > > > > ---------------------------------------------------------------- > Dr Richard Alexander Owen Unix System Administrator > > The Computer Centre E-mail: rao3@le.ac.uk > University of Leicester Tel: (0116) 2525133 > University Road Fax: (0116) 2525027 > Leicester LE1 7RH > ---------------------------------------------------------------- > _______________________________________________ > 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/ *** Software bugs are stupid. Nevertheless it needs not so stupid people to solve them *** =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Heinz Mauelshagen Red Hat GmbH Consulting Development Engineer Am Sonnenhang 11 56242 Marienrachdorf Germany Mauelshagen@RedHat.com +49 2626 141200 FAX 924446 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- _______________________________________________ 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/