summaryrefslogtreecommitdiffstats
path: root/arch/blackfin/mm
diff options
context:
space:
mode:
authorAlexey Dobriyan <adobriyan@gmail.com>2009-03-25 20:48:06 +0100
committerAlexey Dobriyan <adobriyan@gmail.com>2009-03-30 23:14:44 +0200
commit99b76233803beab302123d243eea9e41149804f3 (patch)
tree398178210fe66845ccd6fa4258ba762a87e023ad /arch/blackfin/mm
parentproc 1/2: do PDE usecounting even for ->read_proc, ->write_proc (diff)
downloadlinux-99b76233803beab302123d243eea9e41149804f3.tar.xz
linux-99b76233803beab302123d243eea9e41149804f3.zip
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>
Diffstat (limited to 'arch/blackfin/mm')
-rw-r--r--arch/blackfin/mm/sram-alloc.c1
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/blackfin/mm/sram-alloc.c b/arch/blackfin/mm/sram-alloc.c
index 834cab7438a8..530d1393a232 100644
--- a/arch/blackfin/mm/sram-alloc.c
+++ b/arch/blackfin/mm/sram-alloc.c
@@ -854,7 +854,6 @@ static int __init sram_proc_init(void)
printk(KERN_WARNING "unable to create /proc/sram\n");
return -1;
}
- ptr->owner = THIS_MODULE;
ptr->read_proc = sram_proc_read;
return 0;
}