From: Christian Borntraeger Date: Tue, 2 Dec 2008 10:16:03 +0000 (+0100) Subject: anon_inodes: use fops->owner for module refcount X-Git-Tag: v2.6.29-rc1~539^2~15 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e3a2a0d4e5ace731e60e2eff4fb7056ecb34adc1;p=pandora-kernel.git anon_inodes: use fops->owner for module refcount There is an imbalance for anonymous inodes. If the fops->owner field is set, the module reference count of owner is decreases on release. ("filp_close" --> "__fput" ---> "fops_put") On the other hand, anon_inode_getfd does not increase the module reference count of owner. This causes two problems: - if owner is set, the module refcount goes negative - if owner is not set, the module can be unloaded while code is running This patch changes anon_inode_getfd to be symmetric regarding fops->owner handling. I have checked all existing users of anon_inode_getfd. Noone sets fops->owner, thats why nobody has seen the module refcount negative. The refcounting was tested with a patched and unpatched KVM module.(see patch 2/2) I also did an epoll_open/close test. Signed-off-by: Christian Borntraeger Reviewed-by: Davide Libenzi Signed-off-by: Avi Kivity --- Reading git-diff-tree failed