On Sat, 11 Dec 2010 19:57:11 -0500 Richard Sharpe <realrichardsharpe@xxxxxxxxx> wrote: > On Sat, Dec 11, 2010 at 7:30 PM, Jeff Layton <jlayton@xxxxxxxxx> wrote: > >> > >> Will look into this. One thing that concerns me is if a cached etnry > >> for a SID with its name and an id (either an uid or a gid), if that SID > >> now represents a different object and has differernt name, would > >> not cached info be incorrect? Not sure if this can ever happen > >> or how would it happen and if it does, what would be a trigger > >> for a cache revalidation and purges! > >> > > > > Sure, mappings can change. But, you still have the same problem with > > what you're proposing in these patches. The userspace program isn't > > setting a timeout on the key. Once a mapping is put in the keyring, > > it's there until it's revoked. You probably want to set a max TTL for > > the entries in the cache regardless of what scheme is used. > > I was under the impression that SIDs are never reused. Perhaps I am mistaken. > That may be, but the mapping of a SID is dependent upon settings in config files that could change. It seems reasonable to me to only cache these mappings for a period of time in the event that they do. That period of time could default to being rather long and be tunable. -- Jeff Layton <jlayton@xxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
