Hi Mike, On 05/21/2010 07:26 AM +0900, Mike Snitzer wrote: > Factorize live table type compatibility check into > dm_table_type_matches_live_table(). Catching a conflicting table type > early, during table load, avoids failing during resume -- which always > leaves the DM device suspended. > > So also check type during dm_table_set_type() -- which happens as part > of a table load. But preserve the existing check during resume, in > dm_swap_table(), because a racing table load could stage an inactive > table that conflicts with the table type that dm_swap_table() is about > to make live: As you noted, the additional check in dm_table_set_type() is racy and has no guarantee to detect problematic table loading in some cases. Although I'm not sure such a duplicated racy check is really needed, it will detect most cases and users may be happy with that. So I have no objection, but at least, please put some comments that it's racy in the code below. > +finish: > + if (!dm_table_type_matches_live_table(t)) > + return -EINVAL; > + Thanks, Kiyoshi Ueda -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
