Bug 157629
| Summary: | kernel: dm snapshot oops when using 1024k chunksize | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Benjamin Schweizer <mail> |
| Component: | device-mapper-obsolete | Assignee: | Alasdair Kergon <agk> |
| Status: | CLOSED UPSTREAM | QA Contact: | |
| Severity: | high | Docs Contact: | |
| Priority: | medium | ||
| Version: | 4 | CC: | agk, dwysocha, mattdm, mbroz |
| Target Milestone: | --- | Keywords: | Reopened |
| Target Release: | --- | ||
| Hardware: | i686 | ||
| OS: | Linux | ||
| URL: | http://www.dsb.net/~schweizer/kernel26-lvm2-snapshot.jpg | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2008-03-17 16:18:50 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
|
Description
Benjamin Schweizer
2005-05-13 08:38:06 UTC
There seems to be a similar bug reported on Kerneltrap (http://kerneltrap.org/node/4458). However the filesystem in this bug is XFS where I'm using ext3fs. I've found another bugreport (https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=152162) that describes lvm problems in combination with md raid1. Chris finaly installed kernel-2.6.9-1.667 which solved his problems. After booting into 2.6.9-1.667-i686, lvcreate segfaulted (no kernel panic) and umounting failed on shutdown. However the effect on this scenario was quite similar: the volumes got corrupted and further reboots end with kernel oops. Please try to capture the full details of the oops in readable form. Also confirm the setup: No software raid - just lvm? The snapshot is of a data volume, not a system partition like / or /var ? And how much memory in machine, what architecture, how big is the filesystem etc. ? Hello Alasdair, I've uploaded another screenshot of better quality to http://www.dsb.net/~schweizer/kernel26-lvm2-snapshot.jpg I've installed the latest kernel therefor which is kernel.i686 2.6.11-1.1312_FC4. The bug is similar; however I've figured out that this is not a total freeze. I can type unless there is a disk access. The software setup is as follows: hda1=/boot, hda2=lvm (one single vg called 'storage', no softraid/md/crypto/whatever). The volume group is splited into the logical volumes /root,/usr,/var,/home,/srv and swap. /srv was snapshoted with an initial size of 4gigs and a snapshot size of 2gigs. The volume usage was less than 5 percent and no measurable IOs occured. The oops appeared immediately. I've to mention again that the lvm was created as lvm1 and then converted with vgconvert to lvm2. I've done this on two separate machines. - Pentium III w/ 500 MHz, 256megs RAM and 250gig ATA disk (this is the machine that I've token the screenshot from) - Pentium 4 w/ 3 GHz, 1gig RAM and 120gig ATA disk Both machines are tested and operate well. I would exclude any hardware faults. Hmm, still no response. Do I have to reopen this bugreport withing another release? From looking at the oops, this might (a) be something fixed in 2.6.13-rc4 upstream or (b) another manifestation of bug 132057. So try 2.6.13-rc4; if it still fails you'll have to wait for the larger-scale snapshot changes to be made, I'm afraid. Well, I've done some testing on SLES9. This distro suffers from the same problems. Furthermore, I've tested against Linux 2.6.13.2 - no change so far. For the archive: Finally, I've found out that the crash occurs on all tested kernels (2.6.5-sles9, 2.6.12-fc4, 2.6.11-fc4-betas and 2.6.13.2-vanilla) as long as I use a chunk size of 1024k (which is max). I've successfully created a snapshot on 2.6.5-sles9 using a chunk size of 512k and using default chunk size. I assume an out of bounds error . This report targets the FC3 or FC4 products, which have now been EOL'd. Could you please check that it still applies to a current Fedora release, and either update the target product or close it ? Thanks. Fedora Core 3 and Fedora Core 4 are no longer supported. If you could retest this issue on a current release or on the latest development / test version, we would appreciate that. Otherwise, this bug will be marked as CANTFIX one month from now. Thanks for your help and for your patience. Fedora Core 4 is no longer maintained. Setting status to "INSUFFICIENT_DATA". If you can reproduce this bug in the current Fedora release, please reopen this bug and assign it to the corresponding Fedora version. This bug was fixed in newer kernels; agk provided a patch that adressed this issue, it is available at ftp://ftp.sickos.org/pub/linux/linux2.6.14rc2-dm-snapshot-chunksize-fix.patch |