2022-07-13 03:36:36

by shaozhengchao

Subject: [PATCH] crypto: sahara - don't sleep when in softirq

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 <[email protected]>
---
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

2022-07-22 08:20:13

by Herbert Xu

Subject: Re: [PATCH] crypto: sahara - don't sleep when in softirq

On Wed, Jul 13, 2022 at 11:35:50AM +0800, Zhengchao Shao wrote:
> 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 <[email protected]>
> ---
> 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>

Shouldn't this be replaced with spinlock.h?

Thanks,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt