can't mount XFS from a read-only device

[Emmanuel Florac]

Hello all, 

I'm using a RAID enclosure that provides read-only snapshots. It works
perfectly fine using JFS.
But with XFS, I keep trying and it keeps failing :

XFS mounting filesystem sdb

Ending clean XFS mount for filesystem: sdb

sd 11:0:0:1: [sdc] Result: hostbyte=DID_OK
driverbyte=DRIVER_SENSE,SUGGEST_OK

sd 11:0:0:1: [sdc] Sense Key : Data Protect [current] 

sd 11:0:0:1: [sdc] Add. Sense: Write protected
end_request: I/O error, dev sdc, sector 0
Filesystem "sdc": Disabling barriers, trial barrier write failed
XFS mounting filesystem sdc

sd 11:0:0:1: [sdc] Result: hostbyte=DID_OK
driverbyte=DRIVER_SENSE,SUGGEST_OK

sd 11:0:0:1: [sdc] Sense Key : Data Protect [current] 

sd 11:0:0:1: [sdc] Add. Sense: Write protected
end_request: I/O error, dev sdc, sector 1953792056
xfs_force_shutdown(sdc,0x1) called from line 420 of file
fs/xfs/xfs_rw.c.  Return address = 0xffffffff80381f89

Filesystem "sdc": I/O Error Detected.  Shutting down filesystem: sdc

Please umount the filesystem, and rectify the problem(s)

I/O error in filesystem ("sdc") meta-data dev sdc block
0x74748038       ("xlog_bwrite") error 5 buf count 262144

XFS: failed to locate log tail
XFS: log mount/recovery failed: error 5
XFS: log mount failed

I don't really grasp what's wrong...

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Emmanuel Florac     |   Intellique
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