From patchwork Mon Jun 19 02:43:27 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia-Ju Bai X-Patchwork-Id: 9795049 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 3C69B600C5 for ; Mon, 19 Jun 2017 02:40:55 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1EECB24B44 for ; Mon, 19 Jun 2017 02:40:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 13AD627F95; Mon, 19 Jun 2017 02:40:55 +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=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_HI autolearn=ham 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 B28D624B44 for ; Mon, 19 Jun 2017 02:40:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753298AbdFSCkj (ORCPT ); Sun, 18 Jun 2017 22:40:39 -0400 Received: from m12-12.163.com ([220.181.12.12]:32964 "EHLO m12-12.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753227AbdFSCkh (ORCPT ); Sun, 18 Jun 2017 22:40:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=/peW01a+QbGLyi2ZtT O9TihZeqy2x614PRbOkx7oPp0=; b=P+/Ym9TIl37GveCy9lpxUZ2t1EpiKsjzoV YBefY+dBbisyVHopwEB22P7Xx0I0+1r+LLhaAQ/zfo0MfBBvjg5bwK5ozls23qxg HK7zPS2FJ4qNRrTI2aM9l7rBU3QsVydDSm2anlnAMFHqcp6vYyp55GQlYJLDsQXO mShdfdnzs= Received: from bai-oslab.tsinghua.edu.cn (unknown [166.111.70.19]) by smtp8 (Coremail) with SMTP id DMCowAC34qaUOUdZ3yRdDA--.36241S2; Mon, 19 Jun 2017 10:40:24 +0800 (CST) From: Jia-Ju Bai To: qlogic-storage-upstream@qlogic.com, jejb@linux.vnet.ibm.com, martin.petersen@oracle.com Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] qla4xxx: Fix a sleep-in-atomic bug in qla4_82xx_crb_win_lock Date: Mon, 19 Jun 2017 10:43:27 +0800 Message-Id: <1497840207-4757-1-git-send-email-baijiaju1990@163.com> X-Mailer: git-send-email 1.7.9.5 X-CM-TRANSID: DMCowAC34qaUOUdZ3yRdDA--.36241S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxXF13XrWxtw43WFW3KF15Jwb_yoW5Xw17pF 9Yqas8Cr4UAryjgryDWr1Uur13ua1UKryUCa1xW3yDuFn8CFyavr1qvFyxAFyqq397tas7 XFWkJFy3uF4DXrJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07UIJmUUUUUU= X-Originating-IP: [166.111.70.19] X-CM-SenderInfo: xedlyx5dmximizq6il2tof0z/xtbBRRj7elO-7q7DYwAAsQ Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The driver may sleep under a write spin lock, the function call path is: qla4_82xx_wr_32 (acquire the lock) qla4_82xx_crb_win_lock schedule or cpu_relax To fix it, the lock is released before "schedule" and "cpu_relax", and the lock is acquired again after "schedule" and "cpu_relax". Signed-off-by: Jia-Ju Bai --- drivers/scsi/qla4xxx/ql4_glbl.h | 2 +- drivers/scsi/qla4xxx/ql4_nx.c | 8 +++++--- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/qla4xxx/ql4_glbl.h b/drivers/scsi/qla4xxx/ql4_glbl.h index bce96a5..b723bef 100644 --- a/drivers/scsi/qla4xxx/ql4_glbl.h +++ b/drivers/scsi/qla4xxx/ql4_glbl.h @@ -115,7 +115,7 @@ uint8_t qla4xxx_update_local_ifcb(struct scsi_qla_host *ha, void qla4_82xx_queue_iocb(struct scsi_qla_host *ha); void qla4_82xx_complete_iocb(struct scsi_qla_host *ha); -int qla4_82xx_crb_win_lock(struct scsi_qla_host *); +int qla4_82xx_crb_win_lock(struct scsi_qla_host *, unsigned long *); void qla4_82xx_crb_win_unlock(struct scsi_qla_host *); int qla4_82xx_pci_get_crb_addr_2M(struct scsi_qla_host *, ulong *); void qla4_82xx_wr_32(struct scsi_qla_host *, ulong, u32); diff --git a/drivers/scsi/qla4xxx/ql4_nx.c b/drivers/scsi/qla4xxx/ql4_nx.c index e91abb3..1cf5f4a 100644 --- a/drivers/scsi/qla4xxx/ql4_nx.c +++ b/drivers/scsi/qla4xxx/ql4_nx.c @@ -386,7 +386,7 @@ if (rv == 1) { write_lock_irqsave(&ha->hw_lock, flags); - qla4_82xx_crb_win_lock(ha); + qla4_82xx_crb_win_lock(ha, &flags); qla4_82xx_pci_set_crbwindow_2M(ha, &off); } @@ -410,7 +410,7 @@ uint32_t qla4_82xx_rd_32(struct scsi_qla_host *ha, ulong off) if (rv == 1) { write_lock_irqsave(&ha->hw_lock, flags); - qla4_82xx_crb_win_lock(ha); + qla4_82xx_crb_win_lock(ha, &flags); qla4_82xx_pci_set_crbwindow_2M(ha, &off); } data = readl((void __iomem *)off); @@ -476,7 +476,7 @@ int qla4_82xx_md_wr_32(struct scsi_qla_host *ha, uint32_t off, uint32_t data) #define CRB_WIN_LOCK_TIMEOUT 100000000 -int qla4_82xx_crb_win_lock(struct scsi_qla_host *ha) +int qla4_82xx_crb_win_lock(struct scsi_qla_host *ha, unsigned long *flags) { int i; int done = 0, timeout = 0; @@ -491,6 +491,7 @@ int qla4_82xx_crb_win_lock(struct scsi_qla_host *ha) timeout++; + write_unlock_irqrestore(&ha->hw_lock, *flags); /* Yield CPU */ if (!in_interrupt()) schedule(); @@ -498,6 +499,7 @@ int qla4_82xx_crb_win_lock(struct scsi_qla_host *ha) for (i = 0; i < 20; i++) cpu_relax(); /*This a nop instr on i386*/ } + write_lock_irqsave(&ha->hw_lock, *flags); } qla4_82xx_wr_32(ha, QLA82XX_CRB_WIN_LOCK_ID, ha->func_num); return 0;