Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753429AbdHDXSN (ORCPT ); Fri, 4 Aug 2017 19:18:13 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:46874 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753390AbdHDXSI (ORCPT ); Fri, 4 Aug 2017 19:18:08 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tony Lindgren , Grygorii Strashko , Felipe Balbi , Sasha Levin Subject: [PATCH 4.9 072/105] usb: dwc3: omap: fix race of pm runtime with irq handler in probe Date: Fri, 4 Aug 2017 16:15:40 -0700 Message-Id: <20170804231556.123472323@linuxfoundation.org> X-Mailer: git-send-email 2.13.4 In-Reply-To: <20170804231551.544678194@linuxfoundation.org> References: <20170804231551.544678194@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2472 Lines: 83 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Grygorii Strashko [ Upstream commit 12a7f17fac5b370bec87259e4c718faf563ce900 ] Now races can happen between interrupt handler execution and PM runtime in error handling code path in probe and in dwc3_omap_remove() which will lead to system crash: in probe: ... err1: pm_runtime_put_sync(dev); ^^ PM runtime can race with IRQ handler when deferred probing happening due to extcon pm_runtime_disable(dev); return ret; in dwc3_omap_remove: ... dwc3_omap_disable_irqs(omap); ^^ IRQs are disabled in HW, but handler may still run of_platform_depopulate(omap->dev); pm_runtime_put_sync(&pdev->dev); ^^ PM runtime can race with IRQ handler pm_runtime_disable(&pdev->dev); return 0; So, OMAP DWC3 IRQ need to be disabled before calling pm_runtime_put() in probe and in dwc3_omap_remove(). Acked-by: Tony Lindgren Signed-off-by: Grygorii Strashko Signed-off-by: Felipe Balbi Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/dwc3-omap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/usb/dwc3/dwc3-omap.c +++ b/drivers/usb/dwc3/dwc3-omap.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -511,7 +512,7 @@ static int dwc3_omap_probe(struct platfo /* check the DMA Status */ reg = dwc3_omap_readl(omap->base, USBOTGSS_SYSCONFIG); - + irq_set_status_flags(omap->irq, IRQ_NOAUTOEN); ret = devm_request_threaded_irq(dev, omap->irq, dwc3_omap_interrupt, dwc3_omap_interrupt_thread, IRQF_SHARED, "dwc3-omap", omap); @@ -532,7 +533,7 @@ static int dwc3_omap_probe(struct platfo } dwc3_omap_enable_irqs(omap); - + enable_irq(omap->irq); return 0; err2: @@ -553,6 +554,7 @@ static int dwc3_omap_remove(struct platf extcon_unregister_notifier(omap->edev, EXTCON_USB, &omap->vbus_nb); extcon_unregister_notifier(omap->edev, EXTCON_USB_HOST, &omap->id_nb); dwc3_omap_disable_irqs(omap); + disable_irq(omap->irq); of_platform_depopulate(omap->dev); pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev);