Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755163AbbGZNdB (ORCPT ); Sun, 26 Jul 2015 09:33:01 -0400 Received: from mx2.suse.de ([195.135.220.15]:41435 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754050AbbGZNc7 (ORCPT ); Sun, 26 Jul 2015 09:32:59 -0400 Message-ID: <1437917574.5839.2.camel@suse.com> Subject: Re: [PATCH 3/4] cp210x: Store part number From: Oliver Neukum To: Petr Tesarik Cc: Johan Hovold , Greg Kroah-Hartman , "open list:USB SERIAL SUBSYSTEM" , open list , Petr Tesarik Date: Sun, 26 Jul 2015 15:32:54 +0200 In-Reply-To: <1437720491-28702-4-git-send-email-ptesarik@suse.com> References: <1437720491-28702-1-git-send-email-ptesarik@suse.com> <1437720491-28702-4-git-send-email-ptesarik@suse.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 859 Lines: 24 On Fri, 2015-07-24 at 08:48 +0200, Petr Tesarik wrote: > @@ -872,6 +886,12 @@ static int cp210x_startup(struct usb_serial > *serial) > > usb_set_serial_data(serial, spriv); > > + /* Get the 1-byte part number of the cp210x device */ > + cp210x_control_msg(serial->port[0], CP210X_VENDOR_SPECIFIC, > + REQTYPE_DEVICE_TO_HOST, CP210X_GET_PARTNUM, > + &partnum, 1, USB_CTRL_GET_TIMEOUT); > + spriv->bPartNumber = partnum & 0xFF; DMA on the stack. That breaks the cache coherency rules. You must kmalloc the buffer. Regards Oliver -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/