Bug 441244
| Summary: | parted breaks reloading logical partitions | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 5 | Reporter: | Bryn M. Reeves <bmr> | ||||||
| Component: | parted | Assignee: | Joel Andres Granados <jgranado> | ||||||
| Status: | CLOSED ERRATA | QA Contact: | Alexander Todorov <atodorov> | ||||||
| Severity: | medium | Docs Contact: | |||||||
| Priority: | high | ||||||||
| Version: | 5.2 | CC: | arnaud.gomes, atodorov, james.brown, pasteur, tao | ||||||
| Target Milestone: | rc | ||||||||
| Target Release: | --- | ||||||||
| Hardware: | All | ||||||||
| OS: | Linux | ||||||||
| Whiteboard: | |||||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||||
| Doc Text: | Story Points: | --- | |||||||
| Clone Of: | Environment: | ||||||||
| Last Closed: | 2009-01-20 21:08:43 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: | |||||||||
| Bug Depends On: | |||||||||
| Bug Blocks: | 391501 | ||||||||
| Attachments: |
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Created attachment 301509 [details]
Patch to avoid creating overlapping partitions via BLKPG ioctls
The patch in comment #1 avoids this problem but I'm not sure it's the right fix. The kernel creates the partitions with the overlap between extended/logical for bootloaders to access the EBR, but re-creating this situation is currently not possible using BLKPG ioctl commands. This could probably use some discussion upstream - the effect of this patch can't be any worse than versions of parted prior to commit 26cfacb7.. since these versions simply removed the extended partition completely on a reload, but since the main point of leaving the partition there is for bootloader access it doesn't seem all that useful either. This is the RHEL5 equivalent of bug 218477 I'll commit Bryns patch. Thx. This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release. Created attachment 308956 [details]
extended partition patch
This is the patch I'll apply
This will be present in parted 1.8.1-18
*** Bug 441043 has been marked as a duplicate of this bug. *** An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2009-0110.html |
Description of problem: Versions of parted since 1.8.0 upstream have a problem reloading some extended partitions. This is a regression introduced by commit ID 26cfacb70d75923b23a0e07f1a01ed7ed88622c6. Previous versions of parted would refuse to honor the extended partition when reloading the partition table using parted/partprobe: - /* extended partitions have no business in the kernel! - * blkpg doesn't like overlapping partitions. Hmmm, - * LILO isn't going to like this. - */ - if (part->type & PED_PARTITION_EXTENDED) - continue; - The change included code that mimics the kernel's behavior when reading the partition table (e.g. on device detection or BLKRRPART ioctl), taken from fs/partitions/msdos.c: if (is_extended_partition(p)) { /* prevent someone doing mkfs or mkswap on an extended partition, but leave room for LILO */ put_partition(state, slot, start, size == 1 ? 1 : 2); The corresponding code in parted looks like: + /* see fs/partitions/msdos.c:msdos_partition(): "leave room for LILO" */ + if (part->type & PED_PARTITION_EXTENDED) + linux_part.length = part->geom.length == 1 ? 512 : 1024; + else + linux_part.length = part->geom.length * disk->dev->sector_size; Unfortunately this is not possible using the BLKPG ioctl commands that parted uses to reload the partition table. The kernel enforces strict overlap checking and after adding an extended partition with geom.length != 1 the partition will overlap into what may be the 1st sector of a subsequent logical partition. If this is the case parted will fail with EBUSY when attempting to load this partition. Version-Release number of selected component (if applicable): parted-1.8.1-12.el5 How reproducible: Always with an appropriate partition table. Steps to Reproduce: 1. Create a partition layout that includes an extended partition with length != 1 2. Create logical partitions within this extended partition that begin at the 1st sector of the extended partition 3. partprobe Actual results: # partprobe /dev/sdu Error: Error informing the kernel about modifications to partition /dev/sdu5 -- Device or resource busy. This means Linux won't know about any changes you made to /dev/sdu5 until you reboot -- so you shouldn't mount it or use it in any way before rebooting. # grep sdu /proc/partitions 65 64 5242880 sdu 65 65 900549 sdu1 65 66 900550 sdu2 65 67 900550 sdu3 65 68 1 sdu4 Expected results: # partprobe /dev/sdu # grep sdu /proc/partitions 65 64 5242880 sdu 65 65 900549 sdu1 65 66 900550 sdu2 65 67 900550 sdu3 65 68 1 sdu4 65 69 900549 sdu5 65 70 900549 sdu6 Additional info: Easiest way to set up the partition tables to reproduce is via sfdisk: # cat parted-extended-repro.cmds ,175 ,175 ,175 ,,E ,175 ,175 # cat ~/parted-extended-repro.cmds | sfdisk /dev/sdu Checking that no-one is using this disk right now ... OK Disk /dev/sdu: 1018 cylinders, 166 heads, 62 sectors/track Old situation: Units = cylinders of 5269504 bytes, blocks of 1024 bytes, counting from 0 Device Boot Start End #cyls #blocks Id System /dev/sdu1 0+ 174 175- 900549+ 83 Linux /dev/sdu2 175 349 175 900550 83 Linux /dev/sdu3 350 524 175 900550 83 Linux /dev/sdu4 525 1017 493 2536978 5 Extended /dev/sdu5 525+ 699 175- 900549+ 83 Linux /dev/sdu6 700+ 874 175- 900549+ 83 Linux New situation: Units = cylinders of 5269504 bytes, blocks of 1024 bytes, counting from 0 Device Boot Start End #cyls #blocks Id System /dev/sdu1 0+ 174 175- 900549+ 83 Linux /dev/sdu2 175 349 175 900550 83 Linux /dev/sdu3 350 524 175 900550 83 Linux /dev/sdu4 525 1017 493 2536978 5 Extended /dev/sdu5 525+ 699 175- 900549+ 83 Linux /dev/sdu6 700+ 874 175- 900549+ 83 Linux Warning: no primary partition is marked bootable (active) This does not matter for LILO, but the DOS MBR will not boot this disk. Successfully wrote the new partition table Re-reading the partition table ... If you created or changed a DOS partition, /dev/foo7, say, then use dd(1) to zero the first 512 bytes: dd if=/dev/zero of=/dev/foo7 bs=512 count=1 (See fdisk(8).)