From mboxrd@z Thu Jan 1 00:00:00 1970 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 162F2C433EF for ; Mon, 13 Dec 2021 13:30:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237578AbhLMNaH (ORCPT ); Mon, 13 Dec 2021 08:30:07 -0500 Received: from sin.source.kernel.org ([145.40.73.55]:34656 "EHLO sin.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235637AbhLMNaG (ORCPT ); Mon, 13 Dec 2021 08:30:06 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id EE243CE101C; Mon, 13 Dec 2021 13:30:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67355C34601; Mon, 13 Dec 2021 13:29:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1639402203; bh=sRU8BNAdNf2xyfnyW5j/+kAV8EwcPrmJ6lESbKeGPxo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Y5+rb59S15gUX3TKeSQHKHW0SBmnGiK9aiNCk2YzPMT+JYRrETpLh1Ywf1oVk258J CHxhqTViJDArMbuKlu5Epp3aMRD2O/pzsVBOAO9k3Q5dPprlvYdSIzgjuAWzd7VKsI km99CcLAWoHR2QK1l21o2PS7NiYUhtbIF8v6dT3WCQ7dTC29fW4ayrRGDBO6s8D3Kr 1dxHKps3K7H48ipR7uk5ZcZbQexSNMQGKWsevLbXYRk+7V9GCEREvfXMcxLZXUSFC3 717ADrHpe7RCDNYk02d1RbhPIkgU4fq2mAt8bvckKCEn0m0D7QZYw8lBW+/0L3Xy1+ I6hJtWYaiHO2w== Date: Mon, 13 Dec 2021 21:29:46 +0800 From: Peter Chen To: Pawel Laszczak Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, jianhe@ambarella.com, stable@vger.kernel.org Subject: Re: [PATCH] usb: cdnsp: Fix lack of spin_lock_irqsave/spin_lock_restore Message-ID: <20211213132946.GD5346@Peter> References: <20211213122001.47370-1-pawell@gli-login.cadence.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211213122001.47370-1-pawell@gli-login.cadence.com> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On 21-12-13 13:20:01, Pawel Laszczak wrote: > From: Pawel Laszczak > > Patch puts content of cdnsp_gadget_pullup function inside > spin_lock_irqsave and spin_lock_restore section. > This construction is required here to keep the data consistency, > otherwise some data can be changed e.g. from interrupt context. > > Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver") > Reported-by: Ken (Jian) He > cc: > Signed-off-by: Pawel Laszczak > --- > drivers/usb/cdns3/cdnsp-gadget.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/usb/cdns3/cdnsp-gadget.c b/drivers/usb/cdns3/cdnsp-gadget.c > index f6d231760a6a..d0c040556984 100644 > --- a/drivers/usb/cdns3/cdnsp-gadget.c > +++ b/drivers/usb/cdns3/cdnsp-gadget.c > @@ -1544,8 +1544,10 @@ static int cdnsp_gadget_pullup(struct usb_gadget *gadget, int is_on) > { > struct cdnsp_device *pdev = gadget_to_cdnsp(gadget); > struct cdns *cdns = dev_get_drvdata(pdev->dev); > + unsigned long flags; > > trace_cdnsp_pullup(is_on); > + spin_lock_irqsave(&pdev->lock, flags); If the interrupt bottom half is pending, the consistent issue may still exist, you may let the bottom half has finished first, eg: calling disable_irq before spin_lock_irqsave. Peter > > if (!is_on) { > cdnsp_reset_device(pdev); > @@ -1553,6 +1555,9 @@ static int cdnsp_gadget_pullup(struct usb_gadget *gadget, int is_on) > } else { > cdns_set_vbus(cdns); > } > + > + spin_unlock_irqrestore(&pdev->lock, flags); > + > return 0; > } > > -- > 2.25.1 > -- Thanks, Peter Chen