On Wed, 17 Jul 2013 10:52:31 +0800 Brad Campbell <lists2009@xxxxxxxxxxxxxxx> wrote: > On 17/07/13 02:49, Joe Lawrence wrote: > > Hi Neil, Martin, > > > > While testing patches to fix RAID1 repair GPF crash w/3.10-rc7 > > ( http://thread.gmane.org/gmane.linux.raid/43351 ), I encountered disk > > corruption when repeatedly failing, removing, and adding MD RAID1 > > component disks to their array. The RAID1 was created with an internal > > write bitmap and the test was run against alternating disks in the > > set. I bisected this behavior back to commit 7ceb17e8 "md: Allow > > devices to be re-added to a read-only array", specifically these lines > > of code: > > This sounds like an issue I just bumped up against in RAID-5. > I have a test box with a RAID-5 comprised of 2 x 2TB drives, and 6 > RAID-0's of 2 x 1TB drives. > > > root@test:/root# cat /proc/mdstat > Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] > md3 : active raid5 md20[0] md25[8] md24[7] md22[6] sdl[4] sdn[3] md23[2] > md21[1] > 13673683968 blocks super 1.2 level 5, 512k chunk, algorithm 2 > [8/8] [UUUUUUUU] > bitmap: 0/15 pages [0KB], 65536KB chunk > > md22 : active raid0 sdk[0] sdm[1] > 1953524736 blocks super 1.2 512k chunks > > md20 : active raid0 sdj[0] sdo[1] > 1953522688 blocks super 1.2 512k chunks > > md21 : active raid0 sdh[0] sdi[1] > 1953524736 blocks super 1.2 512k chunks > > md25 : active raid0 sda[0] sdb[1] > 2441900544 blocks super 1.2 512k chunks > > md23 : active raid0 sdd[0] sde[1] > 1953522688 blocks super 1.2 512k chunks > > md24 : active raid0 sdf[0] sdg[1] > 1953524736 blocks super 1.2 512k chunks > > I was running a check over md3 whilst rsyncing a load of data onto it. > md20 was ejected some time during this process. (A smart query issued > caused a timeout on one of the drives). I removed md20, stopped md20, > started md20 and re-added md20. > > This should have caused a re-build as the bitmap would have been way out > of sync, however it immediately reported the rebuild complete and left > the array mostly trashed. (about 500,000 mismatch counts). > > kernel at the time was late in the 3.11-rc1 merge window. > 3.10.0-09289-g9903883 > > I've been meaning to try and reproduce it, but as each operation takes > about 5 hours it's slow going. > > This is a test array, so it has no data value. I'm happy to try to > reproduce this fault if it would help any. > > Regards, > Brad Hi Brad, yes, sounds like the same problem, with same solution for now. Remove the code that Joe highlighted. Thanks. NeilBrown
Attachment:
signature.asc
Description: PGP signature
