• Ed Swierk's avatar
    [PATCH] load_module: no BUG if module_subsys uninitialized · 1cc5f714
    Ed Swierk authored
    Invoking load_module() before param_sysfs_init() is called crashes in
    mod_sysfs_setup(), since the kset in module_subsys is not initialized yet.
    
    In my case, net-pf-1 is getting modprobed as a result of hotplug trying to
    create a UNIX socket.  Calls to hotplug begin after the topology_init
    initcall.
    
    Another patch for the same symptom (module_subsys-initialize-earlier.patch)
    moves param_sysfs_init() to the subsys initcalls, but this is still not
    early enough in the boot process in some cases.  In particular,
    topology_init() causes /sbin/hotplug to run, which requests net-pf-1 (the
    UNIX socket protocol) which can be compiled as a module.  Moving
    param_sysfs_init() to the postcore initcalls fixes this particular race,
    but there might well be other cases where a usermodehelper causes a module
    to load earlier still.
    
    The patch makes load_module() return an error rather than crashing the
    kernel if invoked before module_subsys is initialized.
    
    Cc: Mark Huang <mlhuang@cs.princeton.edu>
    Cc: Greg KH <greg@kroah.com>
    Cc: <stable@kernel.org>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    1cc5f714
module.c 58.8 KB