From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754476AbeDJNyd (ORCPT ); Tue, 10 Apr 2018 09:54:33 -0400 Received: from mail-pf0-f193.google.com ([209.85.192.193]:38000 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753598AbeDJNya (ORCPT ); Tue, 10 Apr 2018 09:54:30 -0400 X-Google-Smtp-Source: AIpwx4+Ljy3pM2mBTUvaY8XDGglczYXAjjqa7vd53HfqyBmrPnfnMjHBi6vgI7lT/5XkqHDkRqFv7w== From: Jia-Ju Bai To: Larry.Finger@lwfinger.net, kvalo@codeaurora.org Cc: linux-wireless@vger.kernel.org, b43-dev@lists.infradead.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] net: wireless: b43legacy: Replace GFP_ATOMIC with GFP_KERNEL in dma_tx_fragment Date: Tue, 10 Apr 2018 21:54:19 +0800 Message-Id: <1523368459-32128-1-git-send-email-baijiaju1990@gmail.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org dma_tx_fragment() is never called in atomic context. dma_tx_fragment() is only called by b43legacy_dma_tx(), which is only called by b43legacy_tx_work(). b43legacy_tx_work() is only set a parameter of INIT_WORK() in b43legacy_wireless_init(). Despite never getting called from atomic context, dma_tx_fragment() calls alloc_skb() with GFP_ATOMIC, which does not sleep for allocation. GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL, which can sleep and improve the possibility of sucessful allocation. This is found by a static analysis tool named DCNS written by myself. And I also manually check it. Signed-off-by: Jia-Ju Bai --- drivers/net/wireless/broadcom/b43legacy/dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/broadcom/b43legacy/dma.c b/drivers/net/wireless/broadcom/b43legacy/dma.c index cfa617d..2f0c64c 100644 --- a/drivers/net/wireless/broadcom/b43legacy/dma.c +++ b/drivers/net/wireless/broadcom/b43legacy/dma.c @@ -1064,7 +1064,7 @@ static int dma_tx_fragment(struct b43legacy_dmaring *ring, meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1); /* create a bounce buffer in zone_dma on mapping failure. */ if (b43legacy_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) { - bounce_skb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA); + bounce_skb = alloc_skb(skb->len, GFP_KERNEL | GFP_DMA); if (!bounce_skb) { ring->current_slot = old_top_slot; ring->used_slots = old_used_slots; -- 1.9.1