From patchwork Sat Sep 1 12:11:05 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: 964877 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="aFmGh7VM"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 422Znz20Dwz9sBn for ; Sat, 1 Sep 2018 22:11:19 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727385AbeIAQXC (ORCPT ); Sat, 1 Sep 2018 12:23:02 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:44208 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726991AbeIAQXC (ORCPT ); Sat, 1 Sep 2018 12:23:02 -0400 Received: by mail-pf1-f193.google.com with SMTP id k21-v6so6680650pff.11; Sat, 01 Sep 2018 05:11:12 -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=urlVOUAThIo2WT+9QwQ1B1RbCWzS5jRVJWYhfhEhD7E=; b=aFmGh7VMR4MejHEx/7yh6o2NlPdJ2bTj94iGyVqi3zwoYHq2uOhFZF5NfJdu7d5s10 nBDdJOzR5Dk9+gDR0hVY17odSmOYCHPKczkXxCmIMKAYqeFLWavDru0fICvbAxLNDEgU zmhCvXRmT34zHrXq3F9V17cmatkxFmnNiYmIqhgb3t9/JJeAzy8nwV6ed1V4gh8tk4ig oxPhMWljYPjw4SF2IgsTcpgXaVf6/KvsDuazMz0pwGndR1N7udzjF2U6NOk5IItU1tpX JD5ADq2azJB6w7f8uMXFSZo/0bK+ONFpG9w8/g0GNv0R5b/hDv9pqfNNYTIo9l0wDW+9 nv3A== 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=urlVOUAThIo2WT+9QwQ1B1RbCWzS5jRVJWYhfhEhD7E=; b=cHFa0OYdqd3Wv5Jwn3iYQ0BEKCNvqKSTIrE/svZrYEocvu5adp5PQPB4yv8jzDgGmC p92T0KHyjz9sldli4PHyDHGsNfg4wRlReIQ/L5Me5gzm9cZH9AIrdOHn9wawCFKnsY1f uiw91mSSDFqVUQ7XyGRO1uceIMZW9gH5ONJDATS+IOZ+a7Ifq/wTzPzzM2G+r1aRKsO3 rEjCxvpLVhFq1YGpFUJU3xnIYWhhdv3kR7O5pImlyngaLcDqyiCd15RtmvcrJK5/KBqD ATF8+18EEQR+fidlN2XtOEft8KgvV+DWB7JG2FRmIa7nvb8rc7ND0JYhAbHNF5gJSzzM FqFw== X-Gm-Message-State: APzg51A9wUoEzGluPNmTD9OVzphjVbFuylfaZUExVwhKNCfOzoKI6j7a DSCLPPfmNBnTGU1Apo6zoAI= X-Google-Smtp-Source: ANB0VdaoMz8afJJdPOyaCYqqpOFt0AUgOH3JV7x+Y8EaTA467H7JIUHV7luk8G6E39dXy5DAeOtuDg== X-Received: by 2002:a65:450a:: with SMTP id n10-v6mr16569946pgq.392.1535803872086; Sat, 01 Sep 2018 05:11:12 -0700 (PDT) Received: from localhost.localdomain ([2402:f000:1:4414:2913:cd09:aee0:380]) by smtp.gmail.com with ESMTPSA id y85-v6sm20189389pfa.170.2018.09.01.05.11.10 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 01 Sep 2018 05:11:11 -0700 (PDT) From: Jia-Ju Bai To: nicolas.ferre@microchip.com, davem@davemloft.net Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] net: cadence: Fix a sleep-in-atomic-context bug in macb_halt_tx() Date: Sat, 1 Sep 2018 20:11:05 +0800 Message-Id: <20180901121105.436-1-baijiaju1990@gmail.com> X-Mailer: git-send-email 2.17.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The kernel module may sleep with holding a spinlock. The function call paths (from bottom to top) in Linux-4.16 are: [FUNC] usleep_range drivers/net/ethernet/cadence/macb_main.c, 648: usleep_range in macb_halt_tx drivers/net/ethernet/cadence/macb_main.c, 730: macb_halt_tx in macb_tx_error_task drivers/net/ethernet/cadence/macb_main.c, 721: _raw_spin_lock_irqsave in macb_tx_error_task To fix this bug, usleep_range() is replaced with udelay(). This bug is found by my static analysis tool DSAC. Signed-off-by: Jia-Ju Bai --- drivers/net/ethernet/cadence/macb_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index a6c911bb5ce2..3dcc31cd4261 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -641,7 +641,7 @@ static int macb_halt_tx(struct macb *bp) if (!(status & MACB_BIT(TGO))) return 0; - usleep_range(10, 250); + udelay(250); } while (time_before(halt_time, timeout)); return -ETIMEDOUT;