Hello.
[I'm not sure that it is a bug, and anyway the problem is solved already.
But maybe someone in linux-kernel mailing list will be interested]
On my server, I am running software raid1 for several months.
It was created from two 80 Gb Segate hard drives, each with a single
partition, /dev/hdf1 and /dev/hdg1. Disks were connected to onboard
Promise RAID controller, that was used just as two more IDE interfaces.
It worked, no problems, no errors.
After a major hardware upgrade, first disk was moved from /dev/hdf (slave
on third IDE interface) to /dev/hde (master on third IDE interface).
I fixed /etc/raiddtab:
raiddev /dev/md0
raid-level 1
nr-raid-disks 2
nr-spare-disks 0
chunk-size 4
device /dev/hde1
raid-disk 0
device /dev/hdg1
raid-disk 1
(before it contained /dev/hdf1 instead of /dev/hde1).
And attempted to start raid (/etc/init.d/raid2 start - it is a Debian Sid
system).
It was not started. And in system logs, I got the following:
Sep 13 16:42:39 zigzag kernel: [events: 00000022]
Sep 13 16:42:39 zigzag kernel: md: could not lock hdf1, zero-size? Marking
faulty.
Sep 13 16:42:39 zigzag kernel: md: could not import hdf1, trying to run
array nevertheless.
Sep 13 16:42:39 zigzag kernel: [events: 00000023]
Sep 13 16:42:39 zigzag kernel: md: autorun ...
Sep 13 16:42:39 zigzag kernel: md: considering hdg1 ...
Sep 13 16:42:39 zigzag kernel: md: adding hdg1 ...
Sep 13 16:42:39 zigzag kernel: md: adding hde1 ...
Sep 13 16:42:39 zigzag kernel: md: created md0
Sep 13 16:42:39 zigzag kernel: md: bind<hde1,1>
Sep 13 16:42:39 zigzag kernel: md: bind<hdg1,2>
Sep 13 16:42:39 zigzag kernel: md: running: <hdg1><hde1>
Sep 13 16:42:39 zigzag kernel: md: hdg1's event counter: 00000023
Sep 13 16:42:39 zigzag kernel: md: hde1's event counter: 00000022
Sep 13 16:42:39 zigzag kernel: md: superblock update time inconsistency --
using the most recent one
Sep 13 16:42:39 zigzag kernel: md: freshest: hdg1
Sep 13 16:42:39 zigzag kernel: md: device name has changed from hdf1 to
hde1 since last import!
Sep 13 16:42:39 zigzag kernel: md: bug in file md.c, line 1322
Sep 13 16:42:39 zigzag kernel:
Sep 13 16:42:39 zigzag kernel: md:^I**********************************
Sep 13 16:42:39 zigzag kernel: md:^I* <COMPLETE RAID STATE PRINTOUT> *
Sep 13 16:42:39 zigzag kernel: md:^I**********************************
Sep 13 16:42:39 zigzag kernel: md0: <hdg1><hde1> array superblock:
Sep 13 16:42:39 zigzag kernel: md: SB: (V:0.90.0)
ID:<839a3cb0.8fd990bd.368c136f.fdcad272> CT:386d2272
Sep 13 16:42:39 zigzag kernel: md: L1 S78150592 ND:1 RD:2 md0 LO:0
CS:4096
Sep 13 16:42:39 zigzag kernel: md: UT:3f6347ef ST:0 AD:1 WD:1 FD:0
SD:0 CSUM:6d6ef950 E:00000023
Sep 13 16:42:39 zigzag kernel: D 0: DISK<N:0,[dev
00:00](0,0),R:0,S:9>
Sep 13 16:42:39 zigzag kernel: D 1: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: THIS: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: rdev hdg1: O:hdg1, SZ:00000000 F:0 DN:1
<6>md: rdev superblock:
Sep 13 16:42:39 zigzag kernel: md: SB: (V:0.90.0)
ID:<839a3cb0.8fd990bd.368c136f.fdcad272> CT:386d2272
Sep 13 16:42:39 zigzag kernel: md: L1 S78150592 ND:1 RD:2 md0 LO:0
CS:4096
Sep 13 16:42:39 zigzag kernel: md: UT:3f6347ef ST:0 AD:1 WD:1 FD:0
SD:0 CSUM:6d6ef950 E:00000023
Sep 13 16:42:39 zigzag kernel: D 0: DISK<N:0,[dev
00:00](0,0),R:0,S:9>
Sep 13 16:42:39 zigzag kernel: D 1: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: THIS: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: rdev hde1: O:hdf1, SZ:00000000 F:0 DN:0
<6>md: rdev superblock:
Sep 13 16:42:39 zigzag kernel: md: SB: (V:0.90.0)
ID:<839a3cb0.8fd990bd.368c136f.fdcad272> CT:386d2272
Sep 13 16:42:39 zigzag kernel: md: L1 S78150592 ND:2 RD:2 md0 LO:0
CS:4096
Sep 13 16:42:39 zigzag kernel: md: UT:3f62c8d7 ST:1 AD:2 WD:2 FD:0
SD:0 CSUM:6d6e7b3b E:00000022
Sep 13 16:42:39 zigzag kernel: D 0: DISK<N:0,hdf1(33,65),R:0,S:6>
Sep 13 16:42:39 zigzag kernel: D 1: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: THIS:
DISK<N:0,hdf1(33,65),R:0,S:6>
Sep 13 16:42:39 zigzag kernel: md:^I**********************************
Sep 13 16:42:39 zigzag kernel:
Sep 13 16:42:39 zigzag kernel: md: bug in file md.c, line 1650
Sep 13 16:42:39 zigzag kernel:
Sep 13 16:42:39 zigzag kernel: md:^I**********************************
Sep 13 16:42:39 zigzag kernel: md:^I* <COMPLETE RAID STATE PRINTOUT> *
Sep 13 16:42:39 zigzag kernel: md:^I**********************************
Sep 13 16:42:39 zigzag kernel: md0: <hdg1><hde1> array superblock:
Sep 13 16:42:39 zigzag kernel: md: SB: (V:0.90.0)
ID:<839a3cb0.8fd990bd.368c136f.fdcad272> CT:386d2272
Sep 13 16:42:39 zigzag kernel: md: L1 S78150592 ND:1 RD:2 md0 LO:0
CS:4096
Sep 13 16:42:39 zigzag kernel: md: UT:3f6347ef ST:0 AD:1 WD:1 FD:0
SD:0 CSUM:6d6ef950 E:00000023
Sep 13 16:42:39 zigzag kernel: D 0: DISK<N:0,[dev
00:00](0,0),R:0,S:9>
Sep 13 16:42:39 zigzag kernel: D 1: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: THIS: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: rdev hdg1: O:hdg1, SZ:00000000 F:0 DN:1
<6>md: rdev superblock:
Sep 13 16:42:39 zigzag kernel: md: SB: (V:0.90.0)
ID:<839a3cb0.8fd990bd.368c136f.fdcad272> CT:386d2272
Sep 13 16:42:39 zigzag kernel: md: L1 S78150592 ND:1 RD:2 md0 LO:0
CS:4096
Sep 13 16:42:39 zigzag kernel: md: UT:3f6347ef ST:0 AD:1 WD:1 FD:0
SD:0 CSUM:6d6ef950 E:00000023
Sep 13 16:42:39 zigzag kernel: D 0: DISK<N:0,[dev
00:00](0,0),R:0,S:9>
Sep 13 16:42:39 zigzag kernel: D 1: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: THIS: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: rdev hde1: O:hdf1, SZ:00000000 F:0 DN:0
<6>md: rdev superblock:
Sep 13 16:42:39 zigzag kernel: md: SB: (V:0.90.0)
ID:<839a3cb0.8fd990bd.368c136f.fdcad272> CT:386d2272
Sep 13 16:42:39 zigzag kernel: md: L1 S78150592 ND:2 RD:2 md0 LO:0
CS:4096
Sep 13 16:42:39 zigzag kernel: md: UT:3f62c8d7 ST:1 AD:2 WD:2 FD:0
SD:0 CSUM:6d6e7b3b E:00000022
Sep 13 16:42:39 zigzag kernel: D 0: DISK<N:0,hdf1(33,65),R:0,S:6>
Sep 13 16:42:39 zigzag kernel: D 1: DISK<N:1,hdg1(34,1),R:1,S:6>
Sep 13 16:42:39 zigzag kernel: md: THIS:
DISK<N:0,hdf1(33,65),R:0,S:6>
Sep 13 16:42:39 zigzag kernel: md:^I**********************************
Sep 13 16:42:39 zigzag kernel:
Sep 13 16:42:39 zigzag kernel: md :do_md_run() returned -22
Sep 13 16:42:39 zigzag kernel: md: md0 stopped.
Sep 13 16:42:39 zigzag kernel: md: unbind<hdg1,1>
Sep 13 16:42:39 zigzag kernel: md: export_rdev(hdg1)
Sep 13 16:42:39 zigzag kernel: md: unbind<hde1,0>
Sep 13 16:42:39 zigzag kernel: md: export_rdev(hde1)
Sep 13 16:42:39 zigzag kernel: md: ... autorun DONE.
I was able to get my raid back (without any data loss) by re-running
mkraid, and since then it works for a week without problems.
But since the log contains lines "bug in md.c", I decided to post this
message to linux-kernel.
That happened with Linux 2.4.22 SMP on dual-athlon server. I will provide
more system information if it is needed.