From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D2B3C47088 for ; Wed, 26 May 2021 20:49:51 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DDFA0613DC for ; Wed, 26 May 2021 20:49:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DDFA0613DC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 652EA6B0036; Wed, 26 May 2021 16:49:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 600F76B006E; Wed, 26 May 2021 16:49:50 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4A11C6B0070; Wed, 26 May 2021 16:49:50 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0111.hostedemail.com [216.40.44.111]) by kanga.kvack.org (Postfix) with ESMTP id 14A946B0036 for ; Wed, 26 May 2021 16:49:50 -0400 (EDT) Received: from smtpin35.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 98163A8FB for ; Wed, 26 May 2021 20:49:49 +0000 (UTC) X-FDA: 78184573698.35.4B2EF28 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf28.hostedemail.com (Postfix) with ESMTP id 377322000981 for ; Wed, 26 May 2021 20:49:42 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 0F4E0611BE; Wed, 26 May 2021 20:49:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1622062183; bh=aG3UINtyIudcCr1jcShtuROgiwkLr+yC67i/e+rJ130=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=OQwH8Nh0p62kPnQVnKw9Qkv+XdO/rDpNJhqsOhVin5GIOJh/KcfPrFp+TCZ0SQxtT HIKBj/oMDfISR9tnVTIv3uFVdY2pchbUAk+iU7zkSYs9T5s+IHs5kuMj9oX5DSNDO7 15hbwX00Wy9vVEFS81Q+EEpxkZp9BzNquTJXj8EU= Date: Wed, 26 May 2021 13:49:42 -0700 From: Andrew Morton To: Thomas Bogendoerfer Cc: linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, =?UTF-8?Q?=E5=91=A8=E7=90=B0=E6=9D=B0?= Subject: Re: [PATCH] Revert "MIPS: make userspace mapping young by default" Message-Id: <20210526134942.2bf26d5cf5a9243583aec131@linux-foundation.org> In-Reply-To: <20210526094335.92948-1-tsbogend@alpha.franken.de> References: <20210526094335.92948-1-tsbogend@alpha.franken.de> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 377322000981 Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=OQwH8Nh0; spf=pass (imf28.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspamd-Server: rspam04 X-Stat-Signature: 7h1bz83xnp971d4pqhi88kyirxzm7mna X-HE-Tag: 1622062182-827210 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000488, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 26 May 2021 11:43:35 +0200 Thomas Bogendoerfer wrote: > This reverts commit f685a533a7fab35c5d069dcd663f59c8e4171a75. > > MIPS cache flush logic needs to know whether the mapping was already > established to decide how to flush caches. This is done by checking the > valid bit in the PTE. The commit above breaks this logic by setting > the valid in the PTE in new mappings, which causes kernel crashes. Thanks. I added Fixes: f685a533a7f ("MIPS: make userspace mapping young by default") Cc: