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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 2556AC433DF for ; Tue, 26 May 2020 19:10:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EFD4A208B3 for ; Tue, 26 May 2020 19:10:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590520252; bh=uRYjAfcBLCDplyNwEKjmFODt4UceFio/YeWgljBxLy0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=F2SKCjg9/1eHRvS/Pjxknz1bqrJUauyMh2KMB4OG7Sw98vOM4Dspmqbc18kAQxYD9 mPcJ4eUn6oBqjeE0+5AvR21+o7cmQyidAo4zxxqtqPuZqk2E/xdxvKqyYc/2a6zqew hbRjcIeaFyO28oOJLyYI90SnSBk7qRQ8kpJHChxs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391768AbgEZTKv (ORCPT ); Tue, 26 May 2020 15:10:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:40014 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390891AbgEZTKo (ORCPT ); Tue, 26 May 2020 15:10:44 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E1EA9208A7; Tue, 26 May 2020 19:10:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590520244; bh=uRYjAfcBLCDplyNwEKjmFODt4UceFio/YeWgljBxLy0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mCJoYVeGR1snWkBBMYg2xi3/4Z8oweuxtrwATAeB1pYxETURmbRIRkuHvxCNJidNp 7VIOIif0qNh1zwuRz9NkvSUOxxPi6yQr34nEuvRuKFXsRWaiLK9s2FHOvykm8lKELd 4/d8drdKsEru+okSFyfuoQuZoEWoYKVFnYJEX6s4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Ellerman , Sasha Levin Subject: [PATCH 5.4 077/111] powerpc/64s: Disable STRICT_KERNEL_RWX Date: Tue, 26 May 2020 20:53:35 +0200 Message-Id: <20200526183940.153290244@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526183932.245016380@linuxfoundation.org> References: <20200526183932.245016380@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 [ Upstream commit 8659a0e0efdd975c73355dbc033f79ba3b31e82c ] 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: Sasha Levin --- arch/powerpc/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 198bbf42e398..3dc5aecdd853 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -133,7 +133,7 @@ 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