linux/arch/powerpc
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
..
boot Merge commit 'origin/master' into next 2009-03-30 14:04:53 +11:00
configs powerpc/85xx: Add support for the "socrates" board (MPC8544). 2009-03-27 06:42:08 -05:00
include/asm Merge commit 'origin/master' into next 2009-03-30 14:04:53 +11:00
kernel proc 2/2: remove struct proc_dir_entry::owner 2009-03-31 01:14:44 +04:00
kvm KVM: ppc: e500: Fix the bug that KVM is unstable in SMP 2009-03-24 11:03:15 +02:00
lib Merge commit 'origin/master' into next 2009-03-11 17:10:07 +11:00
math-emu powerpc/math-emu: Fix efp dependence 2009-03-11 06:00:08 -05:00
mm powerpc/mm: Introduce early_init_mmu() on 64-bit 2009-03-24 13:47:34 +11:00
oprofile powerpc/oprofile: G4 oprofile has variable number of counters 2009-03-11 17:10:16 +11:00
platforms Merge commit 'origin/master' into next 2009-03-30 14:04:53 +11:00
sysdev Merge commit 'origin/master' into next 2009-03-30 14:04:53 +11:00
xmon powerpc: Prepare xmon_save_regs for use with kdump 2008-12-23 15:13:28 +11:00
Kconfig powerpc/kconfig: Kill PPC_MULTIPLATFORM 2009-03-11 17:11:35 +11:00
Kconfig.debug powerpc/kconfig: Kill PPC_MULTIPLATFORM 2009-03-11 17:11:35 +11:00
Makefile powerpc/math-emu: Fix efp dependence 2009-03-11 06:00:08 -05:00