From patchwork Tue Oct 24 08:43:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alice Chao X-Patchwork-Id: 13434060 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C09A1C00A8F for ; Tue, 24 Oct 2023 08:44:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233786AbjJXIoT (ORCPT ); Tue, 24 Oct 2023 04:44:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50080 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232298AbjJXIoR (ORCPT ); Tue, 24 Oct 2023 04:44:17 -0400 Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9A91199; Tue, 24 Oct 2023 01:44:12 -0700 (PDT) X-UUID: 7d13e7f4724911ee8051498923ad61e6-20231024 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=iN/cYNw0UBNU6pS7nhFH1FIimWvZP96iaW/lpJmIqTw=; b=hb5ZPBvOHXRMszD2tulqM6eEWslsMET4yNvb50MwB1e6BgAQ8b56WhUveCOD23wgaUi5JVz5XqjFsAi3P7JFuW4VJAiSml0wl+YVaRzI4UX9JpHNXfB/pqspnD+rVtBdvy/epr8VhKMP4xRRN1/xI67so4y70QRs0BP5Io5mASI=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.32,REQID:55f39eb6-88a8-45b1-94c7-3648bf8656d4,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:5f78ec9,CLOUDID:b48840d7-04a0-4e50-8742-3543eab8cb8e,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:-3,IP:nil,U RL:0,File:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR:NO, DKR:0,DKP:0,BRR:0,BRE:0 X-CID-BVR: 0 X-CID-BAS: 0,_,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-UUID: 7d13e7f4724911ee8051498923ad61e6-20231024 Received: from mtkmbs10n2.mediatek.inc [(172.21.101.183)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1507860021; Tue, 24 Oct 2023 16:44:05 +0800 Received: from mtkmbs11n1.mediatek.inc (172.21.101.185) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Tue, 24 Oct 2023 16:44:03 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Tue, 24 Oct 2023 16:44:03 +0800 From: To: Alim Akhtar , Avri Altman , Bart Van Assche , "James E.J. Bottomley" , "Martin K. Petersen" , Matthias Brugger , AngeloGioacchino Del Regno CC: , , , , , , , , , Alice Chao , , , , Subject: [PATCH 1/1] core: ufs: fix racing issue between force complete and isr Date: Tue, 24 Oct 2023 16:43:21 +0800 Message-ID: <20231024084324.12197-1-alice.chao@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-TM-AS-Product-Ver: SMEX-14.0.0.3152-9.1.1006-23728.005 X-TM-AS-Result: No-10--4.717400-8.000000 X-TMASE-MatchedRID: 4PO3xRYykVLSny9D3D7cj0Zakoam9+aebd6rGhWOAwRNShtWKzkFv8bB l+mdYPNDSJ98p/k48isBtjkcfRMmqZH0YXYnbGozFEUknJ/kEl7dB/CxWTRRuzBqYATSOgWj78T SUWAmEuXDhdFgIBeVjG+CyFalGpOx8YHPyIbJBEDSU+hTwCSC7435hht3qJMTDFM6+OpJabFtlz Lk1e/pyNvWO5JXDjg6gITnGkK0NFNRskXKHhdfKpij9M86UwHhsKHfMTjCprzAgTvs8QFuaX7cG d19dSFd X-TM-AS-User-Approved-Sender: No X-TM-AS-User-Blocked-Sender: No X-TMASE-Result: 10--4.717400-8.000000 X-TMASE-Version: SMEX-14.0.0.3152-9.1.1006-23728.005 X-TM-SNTS-SMTP: 4F8ECFD8968BA5811C9F2C3A81AE4EDBFB36B326E3EB9A5C89A185A3FA9E72622000:8 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: Alice Chao While error handler force complete command (Thread A) and completion irq raising (Thread B) of the same command, it may cause race condition. Below is racing step (from 1 to 6): ufshcd_mcq_compl_pending_transfer (Thread A) 1 if (cmd && !test_bit(SCMD_STATE_COMPLETE, &cmd->state)) { 5 spin_lock_irqsave(&hwq->cq_lock, flags); // wait lock release set_host_byte(cmd, DID_REQUEUE); 6 ufshcd_release_scsi_cmd(hba, lrbp); // access null pointer scsi_done(cmd); spin_unlock_irqrestore(&hwq->cq_lock, flags); } ufshcd_mcq_poll_cqe_lock (Thread B) 2 spin_lock_irqsave(&hwq->cq_lock, flags); ufshcd_mcq_poll_cqe_nolock() ufshcd_compl_one_cqe() 3 ufshcd_release_scsi_cmd() // lrbp->cmd = NULL; 4 spin_unlock_irqrestore(&hwq->cq_lock, flags); Signed-off-by: Alice Chao Reviewed-by: Bart Van Assche --- drivers/ufs/core/ufshcd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 8382e8cfa414..ef6bd146a767 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -5518,13 +5518,13 @@ static void ufshcd_mcq_compl_pending_transfer(struct ufs_hba *hba, * For those cmds of which the cqes are not present * in the cq, complete them explicitly. */ + spin_lock_irqsave(&hwq->cq_lock, flags); if (cmd && !test_bit(SCMD_STATE_COMPLETE, &cmd->state)) { - spin_lock_irqsave(&hwq->cq_lock, flags); set_host_byte(cmd, DID_REQUEUE); ufshcd_release_scsi_cmd(hba, lrbp); scsi_done(cmd); - spin_unlock_irqrestore(&hwq->cq_lock, flags); } + spin_unlock_irqrestore(&hwq->cq_lock, flags); } else { ufshcd_mcq_poll_cqe_lock(hba, hwq); }