The ext4 module uses rcu_call() thus it should use rcu_barrier()on module unload. The kmem cache ext4_pspace_cachep is sometimes free'ed using call_rcu() callbacks. Thus, we must wait for completion of call_rcu() before doing kmem_cache_destroy(). I have difficult determining if no new call_rcu() callbacks can be envoked. Would the maintainer please verify this? Signed-off-by: Jesper Dangaard Brouer <hawk@xxxxxxx> --- fs/ext4/mballoc.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 519a0a6..e271a9e 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2902,8 +2902,10 @@ int __init init_ext4_mballoc(void) void exit_ext4_mballoc(void) { - /* XXX: synchronize_rcu(); */ + /* Wait for completion of call_rcu()'s on ext4_pspace_cachep */ + rcu_barrier(); kmem_cache_destroy(ext4_pspace_cachep); + kmem_cache_destroy(ext4_ac_cachep); kmem_cache_destroy(ext4_free_ext_cachep); } -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html