Re: [PATCH] Busy inodes after unmount, be more verbose in generic_shutdown_super

[Kirill Korotaev <dev@sw.ru>]

>>Olaf, can you please check if my patch for busy inodes from -mm tree 
>>helps you?
>>Patch name is fix-of-dcache-race-leading-to-busy-inodes-on-umount.patch
>>http://www.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.15/2.6.15-mm4/broken-out/fix-of-dcache-race-leading-to-busy-inodes-on-umount.patch
> 
> 
> This patch is just wrong. It is hiding bugs in file systems. The problem is
> that somewhere the reference counting on the vfsmount objects is wrong. The
> file system is unmounted before the last dentry is dereferenced. Either you
> didn't hold a reference to the proper vfsmount objects at all or you
> dereference it too early. See Al Viros patch series (search for "namei fixes")
> on how to fix this issues.

This patch has nothing to do with vfsmount references and doesn't hide 
anything. It just adds syncronization barrier between do_umount() and 
shrink_dcache() since the latter can work with dentries/inodes without 
holding locks.

So if you think there is something wrong with it, please, be more specific.

Kirill