DM suspend locks up under load?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

I'm using some code that creates a snapshot using DM directly (we aren't using LVM), using essentially:

 suspend linear device X
 reload X as a "snapshot-origin" device
 create "snapshot" device
 resume original X device (which is now a snapshot-origin)

This has worked fine for several years.  Recently, however, we updated to a more recent system, and ext4, and are seeing something odd.  Under load, the process above freezes at the first suspend step, and locks up the device in question, requiring a reboot to fix things.

I wrote the attached program to demonstrate the problem.  All it does it call DM_DEVICE_SUSPEND and DM_DEVICE_RESUME over and over on a DM device.  Basically, run the test program on any mounted linear DM target in one shell, then delete a lot of data from a directory residing on that device in another shell.  On my systems this will freeze both the test program and the rm in D state, and require a reboot to fix things.

I've tried multiple different kernels, but at the moment, I'm using kernel-PAE-2.6.35.6-45.fc14.i686 and device-mapper-libs-1.02.63-2.fc14.i686.

One clue I can add is that it only seems to happen if the filesystem on the device is ext4.  It does not happen with ext3.

Any ideas on where I should look next?

Thanks,

David

Attachment: suspendtest.c
Description: Binary data

--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel

[Index of Archives]     [DM Crypt]     [Fedora Desktop]     [ATA RAID]     [Fedora Marketing]     [Fedora Packaging]     [Fedora SELinux]     [Yosemite Discussion]     [KDE Users]     [Fedora Docs]

  Powered by Linux