Bug 494111

Summary: volid recognizing zfs partitions as ext3
Product: [Fedora] Fedora Reporter: Eric Sandeen <esandeen>
Component: util-linux-ngAssignee: Karel Zak <kzak>
Status: CLOSED DUPLICATE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: low    
Version: rawhideCC: harald, kzak
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OS: Linux   
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Last Closed: 2009-10-27 09:13:18 UTC Type: ---
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Description Eric Sandeen 2009-04-04 13:20:37 UTC 
I don't know for sure how much we can do a about this (blkid has the same problem) but bug #494070 and bug #490795 both had users w/ zfs partitions which are recognized as ext3 by both blkid & volid, due to stale ext3 magic.

Really, it would be nice if mkfs.zfs would zero these old signatures, but perhaps we can have better detection of zfs...

I'm not sure what detection algorithm udev uses, but blkid uses VDEV_BOOT_MAGIC, which doesn't seem present in either endianness on the disk snippets I've seen:

# hexdump -C sda2-first-1M | grep "0c b1 07 b0 f5 02 00 00"
# hexdump -C sda2-first-1M | grep "00 00 02 f5 b0 07 b1 0c"

# hexdump -C first_400K | grep "0c b1 07 b0 f5 02 00 00"
# hexdump -C first_400K | grep "00 00 02 f5 b0 07 b1 0c"

but the "uberblock" magic is present in both:

# hexdump -C sda2-first-1M | grep "0c b1 ba 00"
00015e30  30 e8 ff ff 85 c0 5b 75  48 8b 06 35 0c b1 ba 00
# hexdump -C first_400K | grep "0c b1 ba 00"
00015e30  30 e8 ff ff 85 c0 5b 75  48 8b 06 35 0c b1 ba 00

I've asked the person @sun.com who submitted the blkid patch about this, and I can provide the above 2 chunks of data for testing if desired.

Thanks,
-Eric
Comment 1 Bug Zapper 2009-06-09 13:16:38 UTC 
This bug appears to have been reported against 'rawhide' during the Fedora 11 development cycle.
Changing version to '11'.

More information and reason for this action is here:
http://fedoraproject.org/wiki/BugZappers/HouseKeeping
Comment 2 Karel Zak 2009-10-27 09:13:18 UTC 

*** This bug has been marked as a duplicate of bug 494070 ***