Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933259AbcLCBMl (ORCPT ); Fri, 2 Dec 2016 20:12:41 -0500 Received: from smtprelay.synopsys.com ([198.182.60.111]:48994 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932360AbcLCBMj (ORCPT ); Fri, 2 Dec 2016 20:12:39 -0500 Subject: Re: [PATCH] usb: dwc2: fix flags for DMA descriptor allocation in dwc2_hsotg_ep_enable To: Marek Szyprowski , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" References: <1480582931-24433-1-git-send-email-m.szyprowski@samsung.com> CC: John Youn , Bartlomiej Zolnierkiewicz , Felipe Balbi From: John Youn Message-ID: <0a609a5d-7e61-8761-f621-8ef4aec48669@synopsys.com> Date: Fri, 2 Dec 2016 17:12:38 -0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1480582931-24433-1-git-send-email-m.szyprowski@samsung.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.10.186.99] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3585 Lines: 62 On 12/1/2016 1:02 AM, Marek Szyprowski wrote: > dwc2_hsotg_ep_enable can be called from interrupt context, so all > allocations should be done with GFP_ATOMIC flags. This fixes following > issue on ARM architecture: > > [] (unwind_backtrace) from [] (show_stack+0x10/0x14) > [] (show_stack) from [] (dump_stack+0x74/0x94) > [] (dump_stack) from [] (__warn+0xd4/0x100) > [] (__warn) from [] (warn_slowpath_null+0x20/0x28) > [] (warn_slowpath_null) from [] (smp_call_function_many+0xcc/0x2a4) > [] (smp_call_function_many) from [] (on_each_cpu_mask+0x38/0xa8) > [] (on_each_cpu_mask) from [] (start_isolate_page_range+0x134/0x1b8) > [] (start_isolate_page_range) from [] (alloc_contig_range+0xac/0x2f8) > [] (alloc_contig_range) from [] (cma_alloc+0xe0/0x1a8) > [] (cma_alloc) from [] (__alloc_from_contiguous+0x38/0xe0) > [] (__alloc_from_contiguous) from [] (cma_allocator_alloc+0x30/0x38) > [] (cma_allocator_alloc) from [] (__dma_alloc+0x1c0/0x2c8) > [] (__dma_alloc) from [] (arm_dma_alloc+0x3c/0x48) > [] (arm_dma_alloc) from [] (dwc2_hsotg_ep_enable+0xec/0x46c) > [] (dwc2_hsotg_ep_enable) from [] (usb_ep_enable+0x2c/0x3c) > [] (usb_ep_enable) from [] (ecm_set_alt+0xa8/0x154) > [] (ecm_set_alt) from [] (composite_setup+0xd74/0x1540) > [] (composite_setup) from [] (dwc2_hsotg_complete_setup+0xb8/0x370) > [] (dwc2_hsotg_complete_setup) from [] (usb_gadget_giveback_request+0xc/0x10) > [] (usb_gadget_giveback_request) from [] (dwc2_hsotg_complete_request+0x78/0x128) > [] (dwc2_hsotg_complete_request) from [] (dwc2_hsotg_epint+0x69c/0x81c) > [] (dwc2_hsotg_epint) from [] (dwc2_hsotg_irq+0xfc/0x748) > [] (dwc2_hsotg_irq) from [] (__handle_irq_event_percpu+0x58/0x140) > [] (__handle_irq_event_percpu) from [] (handle_irq_event_percpu+0x1c/0x58) > [] (handle_irq_event_percpu) from [] (handle_irq_event+0x38/0x5c) > [] (handle_irq_event) from [] (handle_fasteoi_irq+0xc4/0x19c) > [] (handle_fasteoi_irq) from [] (generic_handle_irq+0x18/0x28) > [] (generic_handle_irq) from [] (__handle_domain_irq+0x6c/0xe4) > [] (__handle_domain_irq) from [] (gic_handle_irq+0x50/0x9c) > [] (gic_handle_irq) from [] (__irq_svc+0x6c/0xa8) > > Fixes: 5f54c54b0ba83 ("usb: dwc2: gadget: Add DDMA chain pointers to > dwc2_hsotg_ep structure") > Signed-off-by: Marek Szyprowski > --- > drivers/usb/dwc2/gadget.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c > index b95930f20d90..c55db4aa54d6 100644 > --- a/drivers/usb/dwc2/gadget.c > +++ b/drivers/usb/dwc2/gadget.c > @@ -3753,7 +3753,7 @@ static int dwc2_hsotg_ep_enable(struct usb_ep *ep, > hs_ep->desc_list = dma_alloc_coherent(hsotg->dev, > MAX_DMA_DESC_NUM_GENERIC * > sizeof(struct dwc2_dma_desc), > - &hs_ep->desc_list_dma, GFP_KERNEL); > + &hs_ep->desc_list_dma, GFP_ATOMIC); > if (!hs_ep->desc_list) { > ret = -ENOMEM; > goto error2; > Acked-by: John Youn Regards, John