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From:   Zhengchao Shao <shaozhengchao@huawei.com>
To:     <linux-crypto@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <herbert@gondor.apana.org.au>, <davem@davemloft.net>
CC:     <javier.martin@vista-silicon.com>, <weiyongjun1@huawei.com>,
        <yuehaibing@huawei.com>, <shaozhengchao@huawei.com>
Subject: [PATCH] crypto: sahara - don't sleep when in softirq
Date:   Wed, 13 Jul 2022 11:35:50 +0800
Message-ID: <20220713033550.118409-1-shaozhengchao@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

Function of sahara_aes_crypt maybe could be called by function
of crypto_skcipher_encrypt during the rx softirq, so it is not
allowed to use mutex lock. This patch is not yet tested.

Fixes: c0c3c89ae347 ("crypto: sahara - replace tasklets with kthread")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
---
 drivers/crypto/sahara.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/crypto/sahara.c b/drivers/crypto/sahara.c
index 457084b344c1..867107b4ed30 100644
--- a/drivers/crypto/sahara.c
+++ b/drivers/crypto/sahara.c
@@ -26,7 +26,6 @@
 #include <linux/kernel.h>
 #include <linux/kthread.h>
 #include <linux/module.h>
-#include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
@@ -196,7 +195,7 @@ struct sahara_dev {
 	void __iomem		*regs_base;
 	struct clk		*clk_ipg;
 	struct clk		*clk_ahb;
-	struct mutex		queue_mutex;
+	spinlock_t		queue_spinlock;
 	struct task_struct	*kthread;
 	struct completion	dma_completion;
 
@@ -642,9 +641,9 @@ static int sahara_aes_crypt(struct skcipher_request *req, unsigned long mode)
 
 	rctx->mode = mode;
 
-	mutex_lock(&dev->queue_mutex);
+	spin_lock_bh(&dev->queue_spinlock);
 	err = crypto_enqueue_request(&dev->queue, &req->base);
-	mutex_unlock(&dev->queue_mutex);
+	spin_unlock_bh(&dev->queue_spinlock);
 
 	wake_up_process(dev->kthread);
 
@@ -1043,10 +1042,10 @@ static int sahara_queue_manage(void *data)
 	do {
 		__set_current_state(TASK_INTERRUPTIBLE);
 
-		mutex_lock(&dev->queue_mutex);
+		spin_lock_bh(&dev->queue_spinlock);
 		backlog = crypto_get_backlog(&dev->queue);
 		async_req = crypto_dequeue_request(&dev->queue);
-		mutex_unlock(&dev->queue_mutex);
+		spin_unlock_bh(&dev->queue_spinlock);
 
 		if (backlog)
 			backlog->complete(backlog, -EINPROGRESS);
@@ -1092,9 +1091,9 @@ static int sahara_sha_enqueue(struct ahash_request *req, int last)
 		rctx->first = 1;
 	}
 
-	mutex_lock(&dev->queue_mutex);
+	spin_lock_bh(&dev->queue_spinlock);
 	ret = crypto_enqueue_request(&dev->queue, &req->base);
-	mutex_unlock(&dev->queue_mutex);
+	spin_unlock_bh(&dev->queue_spinlock);
 
 	wake_up_process(dev->kthread);
 
@@ -1449,7 +1448,7 @@ static int sahara_probe(struct platform_device *pdev)
 
 	crypto_init_queue(&dev->queue, SAHARA_QUEUE_LENGTH);
 
-	mutex_init(&dev->queue_mutex);
+	spin_lock_init(&dev->queue_spinlock);
 
 	dev_ptr = dev;
 
-- 
2.17.1