From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Mon, 07 Oct 2013 10:38:53 +0200 (CEST) Received: from ni.piap.pl ([195.187.100.4]:48769 "EHLO ni.piap.pl" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S6823911Ab3JGIiuqr4Gq (ORCPT ); Mon, 7 Oct 2013 10:38:50 +0200 Received: from ni.piap.pl (localhost.localdomain [127.0.0.1]) by ni.piap.pl (Postfix) with ESMTP id AF81844219D; Mon, 7 Oct 2013 10:38:49 +0200 (CEST) Received: by ni.piap.pl (Postfix, from userid 1015) id AA46E44219E; Mon, 7 Oct 2013 10:38:49 +0200 (CEST) From: khalasa@piap.pl (Krzysztof =?utf-8?Q?Ha=C5=82asa?=) To: linux-mips@linux-mips.org Cc: linux-media@vger.kernel.org References: Date: Mon, 07 Oct 2013 10:38:49 +0200 In-Reply-To: ("Krzysztof =?utf-8?Q?Ha=C5=82as?= =?utf-8?Q?a=22's?= message of "Thu, 03 Oct 2013 16:00:47 +0200") MIME-Version: 1.0 Message-ID: Content-Type: text/plain Subject: Re: Suspected cache coherency problem on V4L2 and AR7100 CPU X-Anti-Virus: Kaspersky Anti-Virus for Linux Mail Server 5.6.44/RELEASE, bases: 20131007 #11164323, check: 20131007 clean Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 38214 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: khalasa@piap.pl Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips Please forgive me my MIPS TLB ignorance. It seems there is a TLB entry pointing to the userspace buffer at the time the kernel pointer (kseg0) is used. Is is an allowed situation on MIPS 24K? buffer: len 0x1000 (first page), userspace pointer 0x77327000, kernel pointer 0x867ac000 (physical address = 0x067ac000) TLB Index: 15 pgmask=4kb va=77326000 asid=be [pa=01149000 c=3 d=1 v=1 g=0] [pa=067ac000 c=3 d=1 v=1 g=0] Should the TLB entry be deleted before using the kernel pointer (which points at the same page)? -- Krzysztof Halasa Research Institute for Automation and Measurements PIAP Al. Jerozolimskie 202, 02-486 Warsaw, Poland