On Monday April 2, akpm@xxxxxxxxxxxxxxxxxxxx wrote: > > What guarantees that *rdev is still valid when delayed_delete() runs? Because that is how kobjects and krefs work. There is an embedded refcount etc etc.. > > And what guarantees that the md module hasn't been rmmodded when > delayed_delete() tries to run? Good point. Nothing. Maybe this patch is needed. Thanks, NeilBrown --------------------------- Avoid a deadlock when removing a device from an md array via sysfs. - fix Make sure any delayed_delete calls finish before module unload. For simplicity, flush the queue when we stop the array. Signed-off-by: Neil Brown <neilb@xxxxxxx> ### Diffstat output ./drivers/md/md.c | 3 +++ 1 file changed, 3 insertions(+) diff .prev/drivers/md/md.c ./drivers/md/md.c --- .prev/drivers/md/md.c 2007-04-02 17:38:46.000000000 +1000 +++ ./drivers/md/md.c 2007-04-02 18:49:24.000000000 +1000 @@ -3410,6 +3410,9 @@ static int do_md_stop(mddev_t * mddev, i sysfs_remove_link(&mddev->kobj, nm); } + /* make sure all delayed_delete calls have finished */ + flush_scheduled_work(); + export_array(mddev); mddev->array_size = 0; - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
