[dm-devel] [Bug 14354] Status of barrier requests in LVM and dm-crypt?

["Theodore Ts'o" <tytso mit edu>]

Hi, I'm trying to track down a problem relating to ext4 problems, in
kernel bugzilla 14354.  Originally it was thought this was a regression
2.6.31->2.6.32-rc1 regression, but the Aneesh Kumar's report shows a
very similar fsck transcript using a 2.6.30-1 kernel (which makes makes
it unclear whether this is really a regression or not), and all three
reports are tied together by the use of device-mapper.  

The fsck logs are consistent barriers being disabled.  As I recall under
some circumstances device mapper silently drops barrier requests --- I
thought this was fixed for device mapper in some cases.  What's the
current status of barrier requests in device mapper?  Are they
faithfully passed for standard (non-RAID) LVM2 volumes?  When was this
changed?   What about dm-crypto volumes?  (One of the reports was with a
dm-crypt volume from what I can tell.)

Thanks,

						- Ted