From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1428649AbcBSU40 (ORCPT ); Fri, 19 Feb 2016 15:56:26 -0500 Received: from mout.kundenserver.de ([212.227.17.10]:54494 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2993747AbcBSU4X (ORCPT ); Fri, 19 Feb 2016 15:56:23 -0500 From: Arnd Bergmann To: Murali Karicheri Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, davem@davemloft.net Subject: Re: [PATCH v2 1/3] net: ti: netcp: restore get/set_pad_info() functionality Date: Fri, 19 Feb 2016 21:56:14 +0100 Message-ID: <8660259.RH6vgAvune@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: <1455904724-17952-2-git-send-email-m-karicheri2@ti.com> References: <1455904724-17952-1-git-send-email-m-karicheri2@ti.com> <1455904724-17952-2-git-send-email-m-karicheri2@ti.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:4nX+mDjlYT77CfHSi9LFm1AaenwYXK+UuzWn3fxUj5nI/oV43d9 TyScMQjSqmxZBcZAto/hhBx80SkDhOs9zJucHitOmahtQybLIeD7xx+fbRa+YnWHUA8sFjl NNbb5EHY37yuTSwWVQavPV1tPk3+kU/9aifJOl9IieYGwwo9U3EJcFWBXqdYywnEahu8FAE K+TwtmT2ByTdWsuqC2F0Q== X-UI-Out-Filterresults: notjunk:1;V01:K0:vOG5ZORhg8Y=:nkDzCHRD1ScWCy2ti0donx DYR5SEO/jZ2nyuIWwm6URVRRNnXBtrDE0TgslIMt1B/BOcPmJDacPBu278kTCdjcA66GVIQf9 uiFoSQSbAH4GNuUcGq2OZN3xvl3sxQUZAEr9ciJFiOjbzi8a9Rp5YunSnggitciaHhgvs+4a2 Gxjz3HlshHU3n5OYGd+Sg9L2dXDk5WqFJzAzxrv10nSpNQxVjWCCzZtw42zTOyKecPAo2YdDN S2ZOIQkwhu8+P6SGkwghw/fyvAKsORp1fCUBD7FhDYDRdPE+xMJyMU+zrJc2v5FG1jRFBh+F9 PdfF8HNCrmRgaS4Frxjnm7VJt95NMyJnz8OUDsAly+lYVG6o2SKcbkUNsmFE/fejk0b5kWeie nGU1obc4rv/CRzf6AVbeMFOtNExXXrkzpB8BDNXMHbG6BMeq+iAqAoyCbHwIJn4u5kVyZzRkg eCPL3ALBcWuj1nQh5OqNjj0vifwCW4y6Qi0HfiMwQSKkOGnMH/Reh7UnmzZZmVrh1LcbNTvG+ bKERRSBhEeeuiLNONj21epW85qsWZqgcLW7I2dTGtocQntiYagjbozt08I88avx53u2UG6DIf y3qhUjjbuhDawQJHV99nvMMMIgffpJfUGq+EX6/h4BTXmH8Y7GSn2vmvHSGzEWG0+FQBNRSIo +loFCNNpN+3LHa5RJ+E61aemYECBliRS1RMoGlBYlCDr1d8Zi3oWiyomN74EfSPThb36j+WoC JR+aG06+/8EbTmZt Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Friday 19 February 2016 12:58:42 Murali Karicheri wrote: > The commit 899077791403 ("netcp: try to reduce type confusion in > descriptors") introduces a regression in Kernel 4.5-rc1 and it breaks > get/set_pad_info() functionality. > > The TI NETCP driver uses pad0 and pad1 fields of knav_dma_desc to > store DMA/MEM buffer pointer and buffer size respectively. And in both > cases for Keystone 2 the pointer type size is 32 bit regardless of > LAPE enabled or not, because CONFIG_ARCH_DMA_ADDR_T_64BIT originally > is not expected to be defined. > > Unfortunately, above commit changed buffer's pointers save/restore > code (get/set_pad_info()) and added intermediate conversation to u64 > which works incorrectly on 32bit Keystone 2 and causes TI NETCP driver > crash in RX/TX path due to "Unable to handle kernel NULL pointer" > exception. This issue was reported and discussed in [1]. > > Hence, fix it by partially reverting above commit and restoring > get/set_pad_info() functionality as it was before. > > [1] https://www.mail-archive.com/netdev@vger.kernel.org/msg95361.html > Cc: Wingman Kwok > Cc: Mugunthan V N > CC: David Laight > CC: Arnd Bergmann > Reported-by: Franklin S Cooper Jr > Signed-off-by: Grygorii Strashko > Signed-off-by: Murali Karicheri > Acked-by: Arnd Bergmann