From: Jia-Ju Bai Date: Fri, 26 Jan 2018 15:57:01 +0000 (+0800) Subject: Bluetooth: btmrvl_main: Replace GFP_ATOMIC with GFP_KERNEL in btmrvl_send_sync_cmd X-Git-Tag: pci-v4.17-changes-2~83^2~421^2~4 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=1ebbf046273e50cf3cbf2ec13d520dc74ab454d4;p=users%2Fdwmw2%2Flinux.git Bluetooth: btmrvl_main: Replace GFP_ATOMIC with GFP_KERNEL in btmrvl_send_sync_cmd After checking all possible call chains to btmrvl_send_sync_cmd(), my tool finds that this function is never called in atomic context, namely never in an interrupt handler or holding a spinlock. And it calls wait_event_interruptible_timeout() after bt_skb_alloc(), so it indicates that btmrvl_send_sync_cmd() can call function which can sleep. Thus GFP_ATOMIC is not necessary, and it can be replaced with GFP_KERNEL. This is found by a static analysis tool named DCNS written by myself. Signed-off-by: Jia-Ju Bai Signed-off-by: Marcel Holtmann --- diff --git a/drivers/bluetooth/btmrvl_main.c b/drivers/bluetooth/btmrvl_main.c index b280d466f05bb..f6c694a1b9b04 100644 --- a/drivers/bluetooth/btmrvl_main.c +++ b/drivers/bluetooth/btmrvl_main.c @@ -183,7 +183,7 @@ static int btmrvl_send_sync_cmd(struct btmrvl_private *priv, u16 opcode, return -EFAULT; } - skb = bt_skb_alloc(HCI_COMMAND_HDR_SIZE + len, GFP_ATOMIC); + skb = bt_skb_alloc(HCI_COMMAND_HDR_SIZE + len, GFP_KERNEL); if (!skb) { BT_ERR("No free skb"); return -ENOMEM;