From: Linus Lüssing Date: Sun, 12 Sep 2010 21:21:52 +0000 (+0200) Subject: Staging: batman-adv: Always synchronize rcu's on module shutdown X-Git-Tag: v2.6.37-rc1~60^2~3^2~604 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=09686b560ff229bc6c87489717dce118c7d2b20b;p=pandora-kernel.git Staging: batman-adv: Always synchronize rcu's on module shutdown During the module shutdown procedure in batman_exit(), a rcu callback is being scheduled (batman_exit -> hardif_remove_interfaces -> hardif_remove_interfae -> call_rcu). However, when the kernel unloads the module, the rcu callback might not have been executed yet, resulting in a "unable to handle kernel paging request" in __rcu_process_callback afterwards, causing the kernel to freeze. The synchronize_net and synchronize_rcu in mesh_free are currently called before the call_rcu in hardif_remove_interface and have no real effect on it. Therefore, we should always flush all rcu callback functions scheduled during the shutdown procedure using synchronize_net. The call to synchronize_rcu can be omitted because synchronize_net already calls it. Signed-off-by: Linus Lüssing Signed-off-by: Sven Eckelmann Signed-off-by: Greg Kroah-Hartman --- Reading git-diff-tree failed