On Tue, Dec 01, 2015 at 09:50:23AM +0100, Jiri Slaby wrote: > On 12/01/2015, 02:11 AM, Josh Poimboeuf wrote: > > When I try to recreate something similar by putting a delay in > > enabled_store(), klp_free_patch() just sleeps on its call to > > kobject_put() until enabled_store() returns. The unregister stack looks > > like: > > > > [<ffffffff812e966b>] __kernfs_remove+0x1fb/0x380 > > [<ffffffff812ea273>] kernfs_remove+0x23/0x40 > > [<ffffffff812ec601>] sysfs_remove_dir+0x51/0x80 > > [<ffffffff81407fb8>] kobject_del+0x18/0x50 > > [<ffffffff8140804a>] kobject_release+0x5a/0x190 > > [<ffffffff81407f27>] kobject_put+0x27/0x50 > > What about _put outside of klp_mutex in klp_unregister_patch (and maybe > the other _put's as well)? Plus Li Bin's patch. This approach sounds the best to me. I think all _put's for the patch kobj need to be outside the mutex. There's also a _put for the patch kobj in the klp_init_patch() error path which needs to be moved out. I think the rest of the _put's (for object and func kobjs) are fine as they are, because they don't have corresponding sysfs functions which get the mutex. -- Josh -- To unsubscribe from this list: send the line "unsubscribe live-patching" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
