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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 957BAC432BE for ; Fri, 27 Aug 2021 13:26:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6EBAA60EE7 for ; Fri, 27 Aug 2021 13:26:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245221AbhH0N1c (ORCPT ); Fri, 27 Aug 2021 09:27:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34516 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231964AbhH0N1b (ORCPT ); Fri, 27 Aug 2021 09:27:31 -0400 Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6EF90C061757 for ; Fri, 27 Aug 2021 06:26:42 -0700 (PDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4Gx0qM6Gz8z9sRf; Fri, 27 Aug 2021 23:26:39 +1000 (AEST) From: Michael Ellerman To: Benjamin Herrenschmidt , Paul Mackerras , Christophe Leroy , fthain@linux-m68k.org, userm57@yahoo.com, Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org In-Reply-To: <4856f5574906e2aec0522be17bf3848a22b2cd0b.1629269345.git.christophe.leroy@csgroup.eu> References: <4856f5574906e2aec0522be17bf3848a22b2cd0b.1629269345.git.christophe.leroy@csgroup.eu> Subject: Re: [PATCH v2] powerpc/32s: Fix random crashes by adding isync() after locking/unlocking KUEP Message-Id: <163007070021.56462.16976826768640062743.b4-ty@ellerman.id.au> Date: Fri, 27 Aug 2021 23:25:00 +1000 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 18 Aug 2021 06:49:29 +0000 (UTC), Christophe Leroy wrote: > Commit b5efec00b671 ("powerpc/32s: Move KUEP locking/unlocking in C") > removed the 'isync' instruction after adding/removing NX bit in user > segments. The reasoning behind this change was that when setting the > NX bit we don't mind it taking effect with delay as the kernel never > executes text from userspace, and when clearing the NX bit this is > to return to userspace and then the 'rfi' should synchronise the > context. > > [...] Applied to powerpc/fixes. [1/1] powerpc/32s: Fix random crashes by adding isync() after locking/unlocking KUEP https://git.kernel.org/powerpc/c/ef486bf448a057a6e2d50e40ae879f7add6585da cheers