Hello Sergey, On Fri, May 22, 2015 at 09:44:11PM +0900, Sergey Senozhatsky wrote: > On (05/22/15 11:12), Marcin Jabrzyk wrote: > > > > > >no. > > > > > >zram already complains about failed comp backend creation. > > >it's in dmesg (or syslog, etc.): > > > > > > "zram: Cannot initialise %s compressing backend" > > > > > OK, now I see that. Sorry for the noise. > > > > >second, there is not much value in exposing zcomp internals, > > >especially when the result is just another line in dmesg output. > > > > From the other hand, the only valid values that can be written are > > in 'comp_algorithm'. > > So when writing other one, returning -EINVAL seems to be reasonable. > > The user would get immediately information that he can't do that, > > now the information can be very deferred in time. > > it's not. > the error message appears in syslog right before we return -EINVAL > back to user. Although Marcin's description is rather misleading, I like the patch. Every admin doesn't watch dmesg output. Even people could change loglevel simply so KERN_INFO would be void in that case. Instant error propagation is more strighforward for user point of view rather than delaying with depending on another event. Thanks. > > -ss > > > I'm not for exposing more internals, but getting -EINVAL would be nice I -- Kind regards, Minchan Kim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>