>>>>> "Ming" == Ming Lin <mlin@xxxxxxxxxx> writes: Ming> Did you mean still use (UINT_MAX >> 9) in blkdev_issue_discard()? Ming> But that doesn't work for dm-thinp. See Kent's suggestion to use Ming> 1<<31. I'm not sure why things are not working for dm-thinp. Presumably Kent's code would split the discard at a granularity boundary so why would that cause problems for dm? In looking at this I just found out that we'll corrupt data on certain SCSI configs with the granularity enforcement in place. I'll have to conjure up a fix for that... -- Martin K. Petersen Oracle Linux Engineering -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel