On 8/4/06, kong wei <viken_one@hotmail.com> wrote:
he problem is may very old. But I have searched this maillist by google. The messages are so much but none can help me. So ask for help here. It's about the patch linux-2.4.18-lvm-VFSlock.patch. The kernel is linux-2.4.21-47EL with above patch been patched. And I also have tried this two patch linux-2.4.21-VFS-lock.patch linux-2.4.21-VFS-lock-erperimental.patch(See attached files) The xfs come from linux-2.4-xfs(http://oss.sgi.com/projects/xfs/). The xfsprogs version is 2.6.13 The lvm version is 1.0.8 Steps to reproduce this problem: 1: Assume a LV(/dev/testvg/testlv) has been created. mkfs.xfs this LV.(mkfs.xfs /dev/testvg/testlv) mount it on directory /LVM. (mount /dev/testvg/testlv /LVM) 2. xfs_freeze -f /LVM 3. lvcreate -L100M -snTEST_SNAPSHOT /dev/testvg/testlv 4. xfs_freeze -u /LVM 5. umount /LVM The the umount command will not return forever, something operator may also hang there as sync. In 2.6.9, after xfs_freeze -f, the operator lvcreate a snapshot may hang. Only xfs_freeze -u in another session. the snapshot can be done. So in 2.4 also should be done like this, It's the problem about the lock s_umount(in fs/super.c) or the lock bd_mount_sem(fs/buffer.c in 2.6kernel). Thanks && Best Regards Wei Kong
Wei, Your taking me back a ways but in the fall of 2002 I did extensive 2.4.x kernel xfs/snapshot testing. I reported any issues I uncovered to the XFS team and they resolved them all. This was prior to XFS being integrated into the mainline kernel. Also the VFS-lock patch was not in the mainline kernel. I was just looking back at an old e-mail I sent to the xfs mailing list and per a status update I sent, the issues I could detect were corrected as of Sept. 3 -2002. http://marc.theaimsgroup.com/?l=linux-xfs&m=103108332308710&w=2 Note that as part of the process I wrote some pretty heavy duty snapshot tests and submitted them to the xfs project. In my tests I did NOT use the VFS-lock patch. Instead I called xfs_freeze -f and xfs_freeze -u as required. There have been issues at times with doing both. ie. You should either use the VFS-lock patch to automatically freeze the filesystem, or you should call xfs_freeze -f, but doing both has caused lockup problems at various times in the kernels history. To see exactly what my snapshot test did see xfstests/068 in the xfs tree. I have not updated the test to work with 2.6.x kernels, so it should still be a good tool to test 2.4.x kernels. That is unless someone else updated it. I'm not part of the core XFS team and I have not been following their mailing list for a couple of years now. Greg -- Greg Freemyer The Norcross Group Forensics for the 21st Century _______________________________________________ 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/
