With kernel 3.6.6-rc1 I got :
n22 ~ # zgrep -e 'EXT4-fs error' -e JBD2 /var/log/messages
2012-11-05T13:40:44.460+01:00 n22 kernel: EXT4-fs error (device sdb3) in ext4_new_inode:933: IO failure
2012-11-05T13:41:25.982+01:00 n22 kernel: EXT4-fs error (device sdb3) in ext4_new_inode:933: IO failure
2012-11-05T13:41:26.543+01:00 n22 kernel: EXT4-fs error (device sdb3): ext4_mb_generate_buddy:741: group 771, 31096 clusters in bitmap, 31095 in gd
2012-11-05T13:41:26.543+01:00 n22 kernel: JBD2: Spotted dirty metadata buffer (dev = sdb3, blocknr = 0). There's a risk of filesystem corruption in case of system crash.
2012-11-05T13:45:02.077+01:00 n22 kernel: EXT4-fs error (device sdb3): ext4_mb_generate_buddy:741: group 1123, 31721 clusters in bitmap, 31720 in gd
2012-11-05T13:45:02.077+01:00 n22 kernel: JBD2: Spotted dirty metadata buffer (dev = sdb3, blocknr = 0). There's a risk of filesystem corruption in case of system crash.
2012-11-05T13:54:41.729+01:00 n22 kernel: EXT4-fs error (device sdb3): mb_free_blocks:1300: group 1123, block 36808224:freeing already freed block (bit 9760)
2012-11-05T13:54:41.729+01:00 n22 kernel: EXT4-fs error (device sdb3): mb_free_blocks:1300: group 771, block 25264846:freeing already freed block (bit 718)
It is an almost stable Gentoo Linux 32 bit, booted from an external USB disk.
What I did at that time was to compile the 3.6.6 final stable kernel.
--
MfG/Sincerely
Toralf Förster
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