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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 8F185C433E1 for ; Mon, 8 Jun 2020 23:18:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60CF520872 for ; Mon, 8 Jun 2020 23:18:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591658332; bh=wF1HNEupuWtrXwQN1wgfUpV+1kvAETiHj3R/MgHdlxI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=TgA3UiiKXxbHEyJYtOIZilpJ/oo8J/B3aAkFGt2UvTTYPL3ffyL7RzArRYFtmqsHJ PJT3f9TxA1hdNh3Pdbov+mYHGU5VGwmgBixtbKzqvnlT/gnaa8ZafVzd1VliCghMP8 WNrWqZ/DaqkO88Q3w+XtA91pXk1/eOyuDFzVbIYQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729213AbgFHXSv (ORCPT ); Mon, 8 Jun 2020 19:18:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:35956 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730004AbgFHXPL (ORCPT ); Mon, 8 Jun 2020 19:15:11 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E7DBB21527; Mon, 8 Jun 2020 23:15:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591658111; bh=wF1HNEupuWtrXwQN1wgfUpV+1kvAETiHj3R/MgHdlxI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=grTUcXeMwBXo0E5KnM0hjnAc1P6ONQ9VS56DxOdysbubs/lyMxdV8Wo16lWvxuyz3 OhvFaaFpTdCj6szIGyV0wskGE14BY7hRH29k//aamracbqEnTYLPD1+5lsX6kmMf/C X5O+Z28pYP55u7NaxMSl4E2Myn3J+4aehCVnf8qs= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Michael Ellerman , Greg Kroah-Hartman , linuxppc-dev@lists.ozlabs.org Subject: [PATCH AUTOSEL 5.6 150/606] powerpc/64s: Disable STRICT_KERNEL_RWX Date: Mon, 8 Jun 2020 19:04:35 -0400 Message-Id: <20200608231211.3363633-150-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200608231211.3363633-1-sashal@kernel.org> References: <20200608231211.3363633-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michael Ellerman commit 8659a0e0efdd975c73355dbc033f79ba3b31e82c upstream. Several strange crashes have been eventually traced back to STRICT_KERNEL_RWX and its interaction with code patching. Various paths in our ftrace, kprobes and other patching code need to be hardened against patching failures, otherwise we can end up running with partially/incorrectly patched ftrace paths, kprobes or jump labels, which can then cause strange crashes. Although fixes for those are in development, they're not -rc material. There also seem to be problems with the underlying strict RWX logic, which needs further debugging. So for now disable STRICT_KERNEL_RWX on 64-bit to prevent people from enabling the option and tripping over the bugs. Fixes: 1e0fc9d1eb2b ("powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs") Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200520133605.972649-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 497b7d0b2d7e..b0fb42b0bf4b 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -129,7 +129,7 @@ config PPC select ARCH_HAS_PTE_SPECIAL select ARCH_HAS_MEMBARRIER_CALLBACKS select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64 - select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !HIBERNATION) + select ARCH_HAS_STRICT_KERNEL_RWX if (PPC32 && !HIBERNATION) select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_UACCESS_FLUSHCACHE select ARCH_HAS_UACCESS_MCSAFE if PPC64 -- 2.25.1