On Fri, May 9, 2008 at 12:42 AM, Mike Snitzer [off-list ref] wrote:

 Was I supposed to use this latest patch in combination with your
 previous patch (to validate_super)?  Because you'll note that with
 your most recent patch nbd0's events (ev1) is still one less than
 sdq's events_cleared.  As such the validate_super's "ev1 <
 mddev->bitmap->events_cleared" check triggers a full rebuild.

 The kernel log shows:
 md: md0 stopped.
 md: bind<nbd0>
 md: bind<sdq>
 md: kicking non-fresh nbd0 from array!
 md: unbind<nbd0>
 md: export_rdev(nbd0)
 raid1: raid set md0 active with 1 out of 2 mirrors
 md0: bitmap initialized from disk: read 13/13 pages, set 0 bits, status: 0

Also, no bits were set in the bitmap.. bitmap_create() must've thrown
away the dirty bits.  Given your latest patch, does bitmap_create()'s
"bitmap->events_cleared == mddev->events" check need to be adjusted?

Before I would always see something like:
md0: bitmap initialized from disk: read 13/13 pages, set 1 bits, status: 0

Mike