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 X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E3115C73C7C for ; Wed, 10 Jul 2019 09:59:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB9DE2084B for ; Wed, 10 Jul 2019 09:59:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727444AbfGJJ76 (ORCPT ); Wed, 10 Jul 2019 05:59:58 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:57505 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725994AbfGJJ76 (ORCPT ); Wed, 10 Jul 2019 05:59:58 -0400 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 512) id 9A9DA8044A; Wed, 10 Jul 2019 11:59:43 +0200 (CEST) Date: Wed, 10 Jul 2019 11:59:10 +0200 From: Pavel Machek To: pavel@ucw.cz Cc: linux-kernel@vger.kernel.org, Sylvain Lemieux , James Grant , Alexandre Belloni , Felipe Balbi , Sasha Levin Subject: Re: [PATCH 5.1 29/96] usb: gadget: udc: lpc32xx: allocate descriptor with GFP_ATOMIC Message-ID: <20190710095910.GA7413@xo-6d-61-c0.localdomain> References: <20190708150526.234572443@linuxfoundation.org> <20190708150528.111562688@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190708150528.111562688@linuxfoundation.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 2019-07-08 17:13:01, Greg Kroah-Hartman wrote: > [ Upstream commit fbc318afadd6e7ae2252d6158cf7d0c5a2132f7d ] > > Gadget drivers may queue request in interrupt context. This would lead to > a descriptor allocation in that context. In that case we would hit > BUG_ON(in_interrupt()) in __get_vm_area_node. > > Also remove the unnecessary cast. GFP_ATOMIC allocations can and do fail, but I don't see any explicit error handling. Can someone check everything is ok? Thanks, Pavel > diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c > index b0781771704e..eafc2a00c96a 100644 > --- a/drivers/usb/gadget/udc/lpc32xx_udc.c > +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c > @@ -922,8 +922,7 @@ static struct lpc32xx_usbd_dd_gad *udc_dd_alloc(struct lpc32xx_udc *udc) > dma_addr_t dma; > struct lpc32xx_usbd_dd_gad *dd; > > - dd = (struct lpc32xx_usbd_dd_gad *) dma_pool_alloc( > - udc->dd_cache, (GFP_KERNEL | GFP_DMA), &dma); > + dd = dma_pool_alloc(udc->dd_cache, GFP_ATOMIC | GFP_DMA, &dma); > if (dd) > dd->this_dma = dma; > > -- > 2.20.1 > > -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html