split_bvec() it is possible that the filesystem and the first level target successfully get bios but the lower level target doesn't because there is no more memory and the pool was drained by upper layers. So the remapping will be stuck forever. To solve this device-mapper core needs to use a private bio_set for each device. Signed-off-by: Stefan Bader Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds !x