From patchwork Tue Apr 10 13:54:19 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia-Ju Bai X-Patchwork-Id: 10333217 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 438BB6028A for ; Tue, 10 Apr 2018 13:54:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 35B6C286F7 for ; Tue, 10 Apr 2018 13:54:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2A2E1287C7; Tue, 10 Apr 2018 13:54:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B146A286F7 for ; Tue, 10 Apr 2018 13:54:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753838AbeDJNyd (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 Received: by mail-pf0-f193.google.com with SMTP id y69so8371650pfb.5; Tue, 10 Apr 2018 06:54:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=K7a2WYSXbnpYBsnQagaopmEFZFsa9OurJHMSEiR5ffk=; b=CpMR3YznQTldXCnupxsFOcVFned4TlZZswEoJ1V8llLPxQvPFbEIgoKtK9/2x/fpCs jmXugTD8MYT3vBzkMPBmFquxgqwm3yKj4JGlqzf6Vq5tLM2d1MBmtcvIU8FdAdixFbRv ceHP1n+dbXBHePp8hfZBU80CsuuD2frNE/pGKo7YDacTE3X5Tgy1Oq4XtyrNsvV6xBUf ZsoN7hbLrcZRbrDeoXYR6c7VmpFIgv66fQ1KPy+34Rk4CkIzXCbRQaxZSH8S/32zRJi/ Cv2TiqnZtMR/PTGIwCdg1hhln9aIiZjb+UoHpW4dn04Dhvcxvq7lN1B9xolxsD9fKQHZ 04qQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=K7a2WYSXbnpYBsnQagaopmEFZFsa9OurJHMSEiR5ffk=; b=tvQs5DGcMvV79dVtzP25MpE6FPOAFgWtWYm7FLxZ/KWbFO6YQ/YqtcyarngRRSl3Gq q4/T+Hpd6oot1OQ/vQXt7YwFbHQH/5srCn7OUYDZykjszpng0w7aMD8V97gyNcJD99nH sNCpJZT3Yz0U47i6rjPdvAaXbhoz+SmJS6NU9yccxW3sUu5K4GnWYiv79pKhVsJTegeO a2f7gsiVqtwMENCWcCetS9zrEvfUf33996Q8ZxWkdLEgPs30MIq3lQrG/4Hol4kTXWkz XB8CaoZ96B++D0nV0gVsMiKGo3zDqckv79CJfBrA2bKSlzP6soq03JW5+kPsUbrBQLE9 1/qQ== X-Gm-Message-State: ALQs6tBr62LLlN9aD2y0nHM3J9d5fWm7sj1/K0LR3uQkXwmOZWRzhLfS Bb01Sgpt1L/c/6rxTip2nCc/h9FF X-Google-Smtp-Source: AIpwx4+Ljy3pM2mBTUvaY8XDGglczYXAjjqa7vd53HfqyBmrPnfnMjHBi6vgI7lT/5XkqHDkRqFv7w== X-Received: by 10.101.86.139 with SMTP id v11mr380827pgs.420.1523368469454; Tue, 10 Apr 2018 06:54:29 -0700 (PDT) Received: from oslab.tsinghua.edu.cn ([2402:f000:1:4413:8dc7:7954:4991:f324]) by smtp.gmail.com with ESMTPSA id q15sm4961720pgv.7.2018.04.10.06.54.25 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 10 Apr 2018 06:54:29 -0700 (PDT) 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-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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;