OpenCloudOS-Kernel/drivers/s390
Alexey Dobriyan 99b7623380 proc 2/2: remove struct proc_dir_entry::owner
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.

We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.

But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.

->read_proc/->write_proc were just fixed to not require ->owner for
protection.

rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.

Removing ->owner will also make PDE smaller.

So, let's nuke it.

Kudos to Jeff Layton for reminding about this, let's say, oversight.

http://bugzilla.kernel.org/show_bug.cgi?id=12454

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:44 +04:00
..
block proc 2/2: remove struct proc_dir_entry::owner 2009-03-31 01:14:44 +04:00
char [S390] BUG to BUG_ON changes 2009-03-26 15:24:28 +01:00
cio Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6 2009-03-26 16:04:22 -07:00
crypto [S390] use kzfree() 2009-03-26 15:24:29 +01:00
kvm s390: remove s390_root_dev_*() 2009-01-06 10:44:34 -08:00
net Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6 2009-03-26 16:04:22 -07:00
scsi [SCSI] zfcp: Report fc_host_port_type as NPIV 2009-03-12 12:58:22 -05:00
Makefile [S390] split/move machine check handler code 2009-03-26 15:24:10 +01:00