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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 67B92C433E1 for ; Mon, 1 Jun 2020 18:05:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4ACEF2077D for ; Mon, 1 Jun 2020 18:05:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591034725; bh=IksiygbT99GRCqa8/aa3+JnLZ2faE/tp8hNH6jKo0dg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UdEpPUAUWoSVcSJ7zOdvac6bXMoRBEbeNG4IlCCrvCKbh7RXm0ZYVmFerCK4RotI8 91Wv2wBg4q1x1nsi0p7WtktRwY/x6zm1+/rUChgCDD+CQtRoJ3mNAye0pwQ1o+4Ecp LqeDxV/9xOu+E+i4BmPNPfhnc1Q9UvDiPRYfBDeo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730321AbgFASFY (ORCPT ); Mon, 1 Jun 2020 14:05:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:50084 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730294AbgFASFF (ORCPT ); Mon, 1 Jun 2020 14:05:05 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A27D22074B; Mon, 1 Jun 2020 18:05:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591034705; bh=IksiygbT99GRCqa8/aa3+JnLZ2faE/tp8hNH6jKo0dg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tYv2xgnbPnb74bt3a4+Rvsl/KkLe3tyny1G16kvqxCYHM39EUYskfHNT+aZkuAbD4 VWT4K9cm1fHveftsYuIe29SxpJEM0e25c+h90ld7nWwua+ga7XHIzJFSUBu0gHTN2y OHXjdogUOZUolg2s7uxPBaiEFVSh4y84XYvIXuA4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sahitya Tummala , Sarthak Garg , Adrian Hunter , Ulf Hansson Subject: [PATCH 4.19 70/95] mmc: core: Fix recursive locking issue in CQE recovery path Date: Mon, 1 Jun 2020 19:54:10 +0200 Message-Id: <20200601174031.830103680@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200601174020.759151073@linuxfoundation.org> References: <20200601174020.759151073@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sarthak Garg commit 39a22f73744d5baee30b5f134ae2e30b668b66ed upstream. Consider the following stack trace -001|raw_spin_lock_irqsave -002|mmc_blk_cqe_complete_rq -003|__blk_mq_complete_request(inline) -003|blk_mq_complete_request(rq) -004|mmc_cqe_timed_out(inline) -004|mmc_mq_timed_out mmc_mq_timed_out acquires the queue_lock for the first time. The mmc_blk_cqe_complete_rq function also tries to acquire the same queue lock resulting in recursive locking where the task is spinning for the same lock which it has already acquired leading to watchdog bark. Fix this issue with the lock only for the required critical section. Cc: Fixes: 1e8e55b67030 ("mmc: block: Add CQE support") Suggested-by: Sahitya Tummala Signed-off-by: Sarthak Garg Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/1588868135-31783-1-git-send-email-vbadigan@codeaurora.org Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/core/queue.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) --- a/drivers/mmc/core/queue.c +++ b/drivers/mmc/core/queue.c @@ -108,7 +108,7 @@ static enum blk_eh_timer_return mmc_cqe_ case MMC_ISSUE_DCMD: if (host->cqe_ops->cqe_timeout(host, mrq, &recovery_needed)) { if (recovery_needed) - __mmc_cqe_recovery_notifier(mq); + mmc_cqe_recovery_notifier(mrq); return BLK_EH_RESET_TIMER; } /* The request has gone already */ @@ -125,18 +125,13 @@ static enum blk_eh_timer_return mmc_mq_t struct request_queue *q = req->q; struct mmc_queue *mq = q->queuedata; unsigned long flags; - int ret; + bool ignore_tout; spin_lock_irqsave(q->queue_lock, flags); - - if (mq->recovery_needed || !mq->use_cqe) - ret = BLK_EH_RESET_TIMER; - else - ret = mmc_cqe_timed_out(req); - + ignore_tout = mq->recovery_needed || !mq->use_cqe; spin_unlock_irqrestore(q->queue_lock, flags); - return ret; + return ignore_tout ? BLK_EH_RESET_TIMER : mmc_cqe_timed_out(req); } static void mmc_mq_recovery_handler(struct work_struct *work)