From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753545AbdDCPMT (ORCPT ); Mon, 3 Apr 2017 11:12:19 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:47382 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752532AbdDCPMS (ORCPT ); Mon, 3 Apr 2017 11:12:18 -0400 Subject: Re: [PATCH 1/7] mfd: cros-ec: Fix host command buffer size To: Lee Jones References: <20170324174407.25401-1-enric.balletbo@collabora.com> <20170324174407.25401-2-enric.balletbo@collabora.com> <20170403142357.2usczfylqbg6cgcx@dell> <20170403143020.mti5vdig6vvlcb2d@dell> Cc: Jonathan Cameron , Olof Johansson , bleung@chromium.org, martinez.javier@gmail.com, Guenter Roeck , Gwendal Grignou , linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, rtc-linux@googlegroups.com, Vic Yang From: Enric Balletbo i Serra Message-ID: <78c54848-3166-4531-2178-0fe73b94727a@collabora.com> Date: Mon, 3 Apr 2017 17:12:13 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <20170403143020.mti5vdig6vvlcb2d@dell> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/04/17 16:30, Lee Jones wrote: > On Mon, 03 Apr 2017, Lee Jones wrote: > >> On Fri, 24 Mar 2017, Enric Balletbo i Serra wrote: >> >>> From: Vic Yang >>> >>> For SPI, we can get up to 32 additional bytes for response preamble. >>> The current overhead (2 bytes) may cause problems when we try to receive >>> a big response. Update it to 32 bytes. >>> >>> Without this fix we could see a kernel BUG when we receive a big response >>> from the Chrome EC when is connected via SPI. >>> >>> Signed-off-by: Vic Yang >>> Tested-by: Enric Balletbo i Serra >>> --- >>> >>> This patch is a FIX, and I think that would be interesting see it merged >>> in this release cycle. This should go through the MFD tree and can be picked >>> independently of the other patches. Lee Jones I think this is for you. >>> >>> include/linux/mfd/cros_ec.h | 3 ++- >>> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> Applied, thanks. > > Scrap that, I'll keep it with the set. > Ok, I'll send a v2 asap with this patch and the few modifications requested on patch 7/7. I'm wondering though if this specific patch could go with current release cycle as (explained above) is a fix and current kernel is affected. Thanks, Enric >>> diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h >>> index b3e812f..3b16c90 100644 >>> --- a/include/linux/mfd/cros_ec.h >>> +++ b/include/linux/mfd/cros_ec.h >>> @@ -35,10 +35,11 @@ >>> * Max bus-specific overhead incurred by request/responses. >>> * I2C requires 1 additional byte for requests. >>> * I2C requires 2 additional bytes for responses. >>> + * SPI requires up to 32 additional bytes for responses. >>> * */ >>> #define EC_PROTO_VERSION_UNKNOWN 0 >>> #define EC_MAX_REQUEST_OVERHEAD 1 >>> -#define EC_MAX_RESPONSE_OVERHEAD 2 >>> +#define EC_MAX_RESPONSE_OVERHEAD 32 >>> >>> /* >>> * Command interface between EC and AP, for LPC, I2C and SPI interfaces. >> >