From patchwork Tue Aug 7 17:47:39 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vivek Gautam X-Patchwork-Id: 10559013 X-Patchwork-Delegate: agross@codeaurora.org Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 05B3D13BB for ; Tue, 7 Aug 2018 17:48:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ED0EC2A0D7 for ; Tue, 7 Aug 2018 17:48:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E0AB72A119; Tue, 7 Aug 2018 17:48:01 +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=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,T_DKIM_INVALID 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 58DF02A0D7 for ; Tue, 7 Aug 2018 17:48:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389744AbeHGUD0 (ORCPT ); Tue, 7 Aug 2018 16:03:26 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:38598 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388788AbeHGUD0 (ORCPT ); Tue, 7 Aug 2018 16:03:26 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 389A060BFA; Tue, 7 Aug 2018 17:47:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1533664079; bh=byN8EJpkilHi0lBBr+pNGYym4JWbt3WYJTmSCqK2es4=; h=From:To:Cc:Subject:Date:From; b=ZAMD0t91Pab7jIoP6mjDQvAkskDogajVuUpKfS7kjCfW+J1q3OU2+QHnQfI7bbxef XzGTPgAxXnMFaiEZDHXD1JcCM2W7BJUHKRkN3LB6xfW78+urM2f4pGz35aDmtDiYX+ KVMlZR6DiA8JsudaS0Ju0gLkKO5kJ8ir4JxxAHH4= Received: from blr-ubuntu-41.ap.qualcomm.com (blr-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.18.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: vivek.gautam@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id D4C5F60BE3; Tue, 7 Aug 2018 17:47:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1533664070; bh=byN8EJpkilHi0lBBr+pNGYym4JWbt3WYJTmSCqK2es4=; h=From:To:Cc:Subject:Date:From; b=IBusA7B0Xz6k3p5X/cbMSu+phjoWSNxaI7/QGW0xPU1dgb94+1M3oQNR8MY8/qDqX EYKUmHnONfMhDP4XLQeWUrBjc6RtiR2Yovlb2LCH/zJJD2A84pYVGFBJ+xsDky6f/F TTwVsr9T1DuswOQrOI1zuK9H8lcZjkd78s61+LXY= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org D4C5F60BE3 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=vivek.gautam@codeaurora.org From: Vivek Gautam To: jejb@linux.vnet.ibm.com, martin.petersen@oracle.com Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Vivek Gautam , Bjorn Andersson , Subhash Jadavani , Matthias Kaehlcke , Evan Green Subject: [PATCH 1/1] scsi/ufshcd: Fix NULL pointer dereference for in ufshcd_init Date: Tue, 7 Aug 2018 23:17:39 +0530 Message-Id: <20180807174739.23379-1-vivek.gautam@codeaurora.org> X-Mailer: git-send-email 2.16.1.72.g5be1f00a9a70 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Error paths in ufshcd_init() ufshcd_hba_exit() killed clk_scaling workqueue when the workqueue is actually created quite late in ufshcd_init(). So, we end up getting NULL pointer dereference in such error paths. Fix this by moving clk_scaling initialization and kill codes to two separate methods, and call them at required places. Fixes: 401f1e4490ee ("scsi: ufs: don't suspend clock scaling during clock gating") Signed-off-by: Vivek Gautam Cc: Bjorn Andersson Cc: Subhash Jadavani Cc: Matthias Kaehlcke Cc: Evan Green Cc: Martin K. Petersen Reviewed-by: Evan Green --- Bjorn, Subhash, I am not certain of some of these devfreq, and clk_scaling bits that are moved as part of this patch. Please help in reviewing the change in the light of these features, and related sequence should be followed. Thanks. drivers/scsi/ufs/ufshcd.c | 53 ++++++++++++++++++++++++++++++----------------- 1 file changed, 34 insertions(+), 19 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 397081d320b1..7273aec95a6c 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1749,6 +1749,34 @@ static ssize_t ufshcd_clkgate_enable_store(struct device *dev, return count; } +static void ufshcd_init_clk_scaling(struct ufs_hba *hba) +{ + char wq_name[sizeof("ufs_clkscaling_00")]; + + if (!ufshcd_is_clkscaling_supported(hba)) + return; + + INIT_WORK(&hba->clk_scaling.suspend_work, + ufshcd_clk_scaling_suspend_work); + INIT_WORK(&hba->clk_scaling.resume_work, + ufshcd_clk_scaling_resume_work); + + snprintf(wq_name, sizeof(wq_name), "ufs_clkscaling_%d", + hba->host->host_no); + hba->clk_scaling.workq = create_singlethread_workqueue(wq_name); + + ufshcd_clkscaling_init_sysfs(hba); +} + +static void ufshcd_exit_clk_scaling(struct ufs_hba *hba) +{ + if (!ufshcd_is_clkscaling_supported(hba)) + return; + + destroy_workqueue(hba->clk_scaling.workq); + ufshcd_devfreq_remove(hba); +} + static void ufshcd_init_clk_gating(struct ufs_hba *hba) { char wq_name[sizeof("ufs_clk_gating_00")]; @@ -6652,6 +6680,7 @@ static int ufshcd_probe_hba(struct ufs_hba *hba) */ if (ret && !ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) { pm_runtime_put_sync(hba->dev); + ufshcd_exit_clk_scaling(hba); ufshcd_hba_exit(hba); } @@ -7187,12 +7216,9 @@ static void ufshcd_hba_exit(struct ufs_hba *hba) ufshcd_variant_hba_exit(hba); ufshcd_setup_vreg(hba, false); ufshcd_suspend_clkscaling(hba); - if (ufshcd_is_clkscaling_supported(hba)) { + if (ufshcd_is_clkscaling_supported(hba)) if (hba->devfreq) ufshcd_suspend_clkscaling(hba); - destroy_workqueue(hba->clk_scaling.workq); - ufshcd_devfreq_remove(hba); - } ufshcd_setup_clocks(hba, false); ufshcd_setup_hba_vreg(hba, false); hba->is_powered = false; @@ -7867,6 +7893,7 @@ void ufshcd_remove(struct ufs_hba *hba) ufshcd_disable_intr(hba, hba->intr_mask); ufshcd_hba_stop(hba, true); + ufshcd_exit_clk_scaling(hba); ufshcd_exit_clk_gating(hba); if (ufshcd_is_clkscaling_supported(hba)) device_remove_file(hba->dev, &hba->clk_scaling.enable_attr); @@ -8031,6 +8058,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) ufshcd_init_clk_gating(hba); + ufshcd_init_clk_scaling(hba); + /* * In order to avoid any spurious interrupt immediately after * registering UFS controller interrupt handler, clear any pending UFS @@ -8069,21 +8098,6 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) goto out_remove_scsi_host; } - if (ufshcd_is_clkscaling_supported(hba)) { - char wq_name[sizeof("ufs_clkscaling_00")]; - - INIT_WORK(&hba->clk_scaling.suspend_work, - ufshcd_clk_scaling_suspend_work); - INIT_WORK(&hba->clk_scaling.resume_work, - ufshcd_clk_scaling_resume_work); - - snprintf(wq_name, sizeof(wq_name), "ufs_clkscaling_%d", - host->host_no); - hba->clk_scaling.workq = create_singlethread_workqueue(wq_name); - - ufshcd_clkscaling_init_sysfs(hba); - } - /* * Set the default power management level for runtime and system PM. * Default power saving mode is to keep UFS link in Hibern8 state @@ -8121,6 +8135,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) out_remove_scsi_host: scsi_remove_host(hba->host); exit_gating: + ufshcd_exit_clk_scaling(hba); ufshcd_exit_clk_gating(hba); out_disable: hba->is_irq_enabled = false;