From patchwork Sun Jun 24 22:08:39 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 10484901 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 5C5ED6023A for ; Sun, 24 Jun 2018 22:09:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 54D2E28857 for ; Sun, 24 Jun 2018 22:09:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 481052885C; Sun, 24 Jun 2018 22:09:21 +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=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, 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 E111F28857 for ; Sun, 24 Jun 2018 22:09:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752151AbeFXWJQ (ORCPT ); Sun, 24 Jun 2018 18:09:16 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:45328 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752026AbeFXWJC (ORCPT ); Sun, 24 Jun 2018 18:09:02 -0400 Received: from localhost ([127.0.0.1] helo=bazinga.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1fXDBo-0000Vg-Uh; Mon, 25 Jun 2018 00:08:57 +0200 From: Sebastian Andrzej Siewior To: linux-usb@vger.kernel.org Cc: tglx@linutronix.de, Greg Kroah-Hartman , John Ogness , Sebastian Andrzej Siewior Subject: [PATCH 06/12] usb: usb-skeleton: use irqsave() in USB's complete callback Date: Mon, 25 Jun 2018 00:08:39 +0200 Message-Id: <20180624220845.6726-7-bigeasy@linutronix.de> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180624220845.6726-1-bigeasy@linutronix.de> References: <20180624220845.6726-1-bigeasy@linutronix.de> MIME-Version: 1.0 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: John Ogness The USB completion callback does not disable interrupts while acquiring the lock. We want to remove the local_irq_disable() invocation from __usb_hcd_giveback_urb() and therefore it is required for the callback handler to disable the interrupts while acquiring the lock. The callback may be invoked either in IRQ or BH context depending on the USB host controller. Use the _irqsave() variant of the locking primitives. Cc: Greg Kroah-Hartman Signed-off-by: John Ogness Signed-off-by: Sebastian Andrzej Siewior --- drivers/usb/usb-skeleton.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/usb/usb-skeleton.c b/drivers/usb/usb-skeleton.c index c3ddd0f1f449..f101347e3ea3 100644 --- a/drivers/usb/usb-skeleton.c +++ b/drivers/usb/usb-skeleton.c @@ -159,10 +159,11 @@ static int skel_flush(struct file *file, fl_owner_t id) static void skel_read_bulk_callback(struct urb *urb) { struct usb_skel *dev; + unsigned long flags; dev = urb->context; - spin_lock(&dev->err_lock); + spin_lock_irqsave(&dev->err_lock, flags); /* sync/async unlink faults aren't errors */ if (urb->status) { if (!(urb->status == -ENOENT || @@ -177,7 +178,7 @@ static void skel_read_bulk_callback(struct urb *urb) dev->bulk_in_filled = urb->actual_length; } dev->ongoing_read = 0; - spin_unlock(&dev->err_lock); + spin_unlock_irqrestore(&dev->err_lock, flags); wake_up_interruptible(&dev->bulk_in_wait); } @@ -331,6 +332,7 @@ static ssize_t skel_read(struct file *file, char *buffer, size_t count, static void skel_write_bulk_callback(struct urb *urb) { struct usb_skel *dev; + unsigned long flags; dev = urb->context; @@ -343,9 +345,9 @@ static void skel_write_bulk_callback(struct urb *urb) "%s - nonzero write bulk status received: %d\n", __func__, urb->status); - spin_lock(&dev->err_lock); + spin_lock_irqsave(&dev->err_lock, flags); dev->errors = urb->status; - spin_unlock(&dev->err_lock); + spin_unlock_irqrestore(&dev->err_lock, flags); } /* free up our allocated buffer */