From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A020BC433ED for ; Wed, 19 May 2021 19:26:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80B4C6108D for ; Wed, 19 May 2021 19:26:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232042AbhEST13 (ORCPT ); Wed, 19 May 2021 15:27:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52684 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229689AbhEST11 (ORCPT ); Wed, 19 May 2021 15:27:27 -0400 Received: from mail.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C36E1C06175F; Wed, 19 May 2021 12:26:06 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) by mail.monkeyblade.net (Postfix) with ESMTPSA id ECB844D25C1D0; Wed, 19 May 2021 12:26:05 -0700 (PDT) Date: Wed, 19 May 2021 12:26:05 -0700 (PDT) Message-Id: <20210519.122605.1971627339402718160.davem@davemloft.net> To: zheyuma97@gmail.com Cc: GR-Linux-NIC-Dev@marvell.com, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net/qla3xxx: fix schedule while atomic in ql_sem_spinlock From: David Miller In-Reply-To: <1621406954-1130-1-git-send-email-zheyuma97@gmail.com> References: <1621406954-1130-1-git-send-email-zheyuma97@gmail.com> X-Mailer: Mew version 6.8 on Emacs 27.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.6.2 (mail.monkeyblade.net [0.0.0.0]); Wed, 19 May 2021 12:26:06 -0700 (PDT) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Zheyu Ma Date: Wed, 19 May 2021 06:49:14 +0000 > When calling the 'ql_sem_spinlock', the driver has already acquired the > spin lock, so the driver should not call 'ssleep' in atomic context. > > This bug can be fixed by unlocking before calling 'ssleep'. ... > diff --git a/drivers/net/ethernet/qlogic/qla3xxx.c b/drivers/net/ethernet/qlogic/qla3xxx.c > index 214e347097a7..af7c142a066f 100644 > --- a/drivers/net/ethernet/qlogic/qla3xxx.c > +++ b/drivers/net/ethernet/qlogic/qla3xxx.c > @@ -114,7 +114,9 @@ static int ql_sem_spinlock(struct ql3_adapter *qdev, > value = readl(&port_regs->CommonRegs.semaphoreReg); > if ((value & (sem_mask >> 16)) == sem_bits) > return 0; > + spin_unlock_irq(&qdev->hw_lock); > ssleep(1); > + spin_lock_irq(&qdev->hw_lock); > } while (--seconds); > return -1; > } Are you sure dropping the lock like this dos not introduce a race condition? Thank you.