iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

padata: Fix wrong usage of rcu_dereference()

Browse Source 
A kernel with enabled lockdep complains about the wrong usage of
rcu_dereference() under a rcu_read_lock_bh() protected region.

  ===============================
  [ INFO: suspicious RCU usage. ]
  3.13.0-rc1+ #126 Not tainted
  -------------------------------
  linux/kernel/padata.c:115 suspicious rcu_dereference_check() usage!

  other info that might help us debug this:

  rcu_scheduler_active = 1, debug_locks = 1
  1 lock held by cryptomgr_test/153:
   #0:  (rcu_read_lock_bh){.+....}, at: [<ffffffff8115c235>] padata_do_parallel+0x5/0x270

Fix that by using rcu_dereference_bh() instead.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Mathias Krause 2013-11-28 19:20:05 +01:00 committed by Herbert Xu
parent 3110e4006c
commit c0e656b7a6
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
kernel/padata.c
View File

@ -112,7 +112,7 @@ int padata_do_parallel(struct padata_instance *pinst,
rcu_read_lock_bh();
pd = rcu_dereference(pinst->pd);
pd = rcu_dereference_bh(pinst->pd);
err = -EINVAL;
if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID)