> > > > What is left is the guarantee, that the race-free r/o remounts will > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > > > always work and some obscure caller didn't forget to surround it with > ^^^^^^^^^^^^^^^^^ > > > Why are those so important? Yes, if we have multiple vfs_() calls, > > surround them with an extra want/drop pair. > > Which leaves you with the same need to audit all these suckers anyway. Not really. Missing such calls would just make the *caller* buggy (i.e. racy with remount r/o), but it would not make the *filesystem* buggy. Big difference. > I'm in principle fine with having such helper functions, *IF* they are > not sold as providing all protection one needs, I'm not selling them as that. > *IF* you are not expecting > to be able to fold all areas down into them and *IF* original ones are > left intact. Left intact for whom, specifically? Another question you've managed to avoid answering. > Modulo the like path_rename(), BTW - that one is just plain ugly API. I'm all open to improvements. > > > let alone removing the interface that doesn't require checks to be > > > vfsmount-based for all users. > > > > What users? There are paractically _no_ other users. The ones that > > there are (like reiserfs) should not be using them, and there are > > already some patches cleaning that mess up. > > OK, explain me, in small words, WTF should something that wants to do > operations on filesystem tree have a vfsmount. Slowly. And "r/o > bind loses value if it can be bypassed" is a hogwash - fs methods are > still there, so it *can* be bypassed just fine, thank you very much. And we know what to do with such users. > It's really up to caller. "But they won't be able to do open()" also > doesn't fly - again, it's up to whoever writes particular piece of code. I understand your theory. But it has zero practical significance. IOW it doesn't matter that someone _may_ want to access the filesystem without a vfsmount, if that someone doesn't exist. Miklos -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
