2018-07-23 08:18:51

by Jia-Ju Bai

[permalink] [raw]
Subject: [PATCH] crypto: cavium: nitrox: Replace GFP_ATOMIC with GFP_KERNEL in crypto_alloc_context()

crypto_alloc_context() is only called by nitrox_skcipher_init(), which is
never called in atomic context.

crypto_alloc_context() calls dma_pool_alloc() with GFP_ATOMIC,
which is not necessary.
GFP_ATOMIC can be replaced with GFP_KERNEL.

This is found by a static analysis tool named DCNS written by myself.
I also manually check the kernel code before reporting it.

Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/crypto/cavium/nitrox/nitrox_lib.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/crypto/cavium/nitrox/nitrox_lib.c b/drivers/crypto/cavium/nitrox/nitrox_lib.c
index 4fdc921ba611..ebe267379ac9 100644
--- a/drivers/crypto/cavium/nitrox/nitrox_lib.c
+++ b/drivers/crypto/cavium/nitrox/nitrox_lib.c
@@ -148,7 +148,7 @@ void *crypto_alloc_context(struct nitrox_device *ndev)
void *vaddr;
dma_addr_t dma;

- vaddr = dma_pool_alloc(ndev->ctx_pool, (GFP_ATOMIC | __GFP_ZERO), &dma);
+ vaddr = dma_pool_alloc(ndev->ctx_pool, (GFP_KERNEL | __GFP_ZERO), &dma);
if (!vaddr)
return NULL;

--
2.17.0



2018-08-03 13:59:18

by Herbert Xu

[permalink] [raw]
Subject: Re: [PATCH] crypto: cavium: nitrox: Replace GFP_ATOMIC with GFP_KERNEL in crypto_alloc_context()

On Mon, Jul 23, 2018 at 04:14:26PM +0800, Jia-Ju Bai wrote:
> crypto_alloc_context() is only called by nitrox_skcipher_init(), which is
> never called in atomic context.
>
> crypto_alloc_context() calls dma_pool_alloc() with GFP_ATOMIC,
> which is not necessary.
> GFP_ATOMIC can be replaced with GFP_KERNEL.
>
> This is found by a static analysis tool named DCNS written by myself.
> I also manually check the kernel code before reporting it.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>

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