[PATCH 4.15 045/163] crypto: sun4i_ss_prng - convert lock to _bh in sun4i_ss_prng_generate

From: Greg Kroah-Hartman
Date: Wed Feb 21 2018 - 08:07:42 EST


4.15-stable review patch. If anyone has any objections, please let me know.

------------------

From: Artem Savkov <artem.savkov@xxxxxxxxx>

commit 2e7d1d61ea6c0f1c4da5eb82cafac750d55637a7 upstream.

Lockdep detects a possible deadlock in sun4i_ss_prng_generate() and
throws an "inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage" warning.
Disabling softirqs to fix this.

Fixes: b8ae5c7387ad ("crypto: sun4i-ss - support the Security System PRNG")
Signed-off-by: Artem Savkov <artem.savkov@xxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/crypto/sunxi-ss/sun4i-ss-prng.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/crypto/sunxi-ss/sun4i-ss-prng.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-prng.c
@@ -28,7 +28,7 @@ int sun4i_ss_prng_generate(struct crypto
algt = container_of(alg, struct sun4i_ss_alg_template, alg.rng);
ss = algt->ss;

- spin_lock(&ss->slock);
+ spin_lock_bh(&ss->slock);

writel(mode, ss->base + SS_CTL);

@@ -51,6 +51,6 @@ int sun4i_ss_prng_generate(struct crypto
}

writel(0, ss->base + SS_CTL);
- spin_unlock(&ss->slock);
+ spin_unlock_bh(&ss->slock);
return 0;
}