crypto: rockchip - fix possible deadlock
authorHeiko Stuebner <heiko@sntech.de>
Sat, 28 Nov 2015 12:27:48 +0000 (13:27 +0100)
committerHerbert Xu <herbert@gondor.apana.org.au>
Fri, 4 Dec 2015 14:21:48 +0000 (22:21 +0800)
commitac7c8e6b6dc959d285382c7e9cdfe608205f0c68
treeaab53ef57ac6dfc64a10bfc00e64d9c81bfad4ee
parent1ab87298cb59b649d8d648d25dc15b36ab865f5a
crypto: rockchip - fix possible deadlock

Lockdep warns about a possible deadlock resulting from the use of regular
spin_locks:

=================================
[ INFO: inconsistent lock state ]
4.4.0-rc2+ #2724 Not tainted
---------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
ksoftirqd/0/3 [HC0[0]:SC1[1]:HE1:SE0] takes:
(&(&crypto_info->lock)->rlock){+.?...}, at: [<bf14a65c>] rk_crypto_tasklet_cb+0x24/0xb4 [rk_crypto]
{SOFTIRQ-ON-W} state was registered at:
  [<c007f4ac>] lock_acquire+0x178/0x218
  [<c0759bac>] _raw_spin_lock+0x54/0x64
  [<bf14af88>] rk_handle_req+0x7c/0xbc [rk_crypto]
  [<bf14b040>] rk_des_ecb_encrypt+0x2c/0x30 [rk_crypto]
  [<bf14b05c>] rk_aes_ecb_encrypt+0x18/0x1c [rk_crypto]
  [<c028c820>] skcipher_encrypt_ablkcipher+0x64/0x68
  [<c0290770>] __test_skcipher+0x2a8/0x8dc
  [<c0292e94>] test_skcipher+0x38/0xc4
  [<c0292fb0>] alg_test_skcipher+0x90/0xb0
  [<c0292158>] alg_test+0x1e8/0x280
  [<c028f6f4>] cryptomgr_test+0x34/0x54
  [<c004bbe8>] kthread+0xf4/0x10c
  [<c0010010>] ret_from_fork+0x14/0x24
irq event stamp: 10672
hardirqs last  enabled at (10672): [<c002fac8>] tasklet_action+0x48/0x104
hardirqs last disabled at (10671): [<c002faa0>] tasklet_action+0x20/0x104
softirqs last  enabled at (10658): [<c002ef84>] __do_softirq+0x358/0x49c
softirqs last disabled at (10669): [<c002f108>] run_ksoftirqd+0x40/0x80

other info that might help us debug this:
Possible unsafe locking scenario:

    CPU0
    ----
  lock(&(&crypto_info->lock)->rlock);
  <Interrupt>
    lock(&(&crypto_info->lock)->rlock);

 *** DEADLOCK ***

Fix this by moving to irq-disabling spinlocks.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
drivers/crypto/rockchip/rk3288_crypto.c
drivers/crypto/rockchip/rk3288_crypto_ablkcipher.c