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=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 69DDBC433E2 for ; Thu, 10 Sep 2020 23:56:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0DCD32065E for ; Thu, 10 Sep 2020 23:56:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ellerman.id.au header.i=@ellerman.id.au header.b="fiF0C/7y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725385AbgIJX4R (ORCPT ); Thu, 10 Sep 2020 19:56:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59942 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725275AbgIJX4Q (ORCPT ); Thu, 10 Sep 2020 19:56:16 -0400 Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 08D61C061573 for ; Thu, 10 Sep 2020 16:56:15 -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 4BnbPl66bTz9sTH; Fri, 11 Sep 2020 09:56:11 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1599782172; bh=fhFJZ8tEpaeqeNQqQJBDCnkVPmjyjoBOeg1MMkx7t98=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=fiF0C/7y/PY6O3hcXo1Lr0G8h2KUoVOQ0yVIE95pe3SzigpO7zLBaU0q7fC52lQHE fDUggJ33LnNs+9gSvqqzLLLfb5FBEou6AgsTAkNP8Kw6cP0RBT5OFuFVmXly5iGAq6 gu4ynJxXjgXP7uc6eJs6G3p/JctST3uW7jly9pOqoofjEgHRsK8DxCKyttV8upoKgq R/UQplVajVpJdw0Od7AmphrWhKG4QyireE9PHNQqxnIL6TNJDu2UXMU9CB/pAjASSH l8GnvM2fyZZ/+ewjYZlQVdYudyZ/dgbEgWOATDzulYjrbbe6gRrPj1Tt1QWvph2+TH df2raJL1uDicw== From: Michael Ellerman To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH] powerpc/powermac: Fix low_sleep_handler with KUAP and KUEP In-Reply-To: <74472ea2a7e8698273643cde7d382bd9f31cd1dd.1598945727.git.christophe.leroy@csgroup.eu> References: <74472ea2a7e8698273643cde7d382bd9f31cd1dd.1598945727.git.christophe.leroy@csgroup.eu> Date: Fri, 11 Sep 2020 09:56:10 +1000 Message-ID: <871rj9rxt1.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christophe Leroy writes: > low_sleep_handler() has an hardcoded restore of segment registers > that doesn't take KUAP and KUEP into account. > > Use head_32's load_segment_registers() routine instead. > > Signed-off-by: Christophe Leroy > Fixes: a68c31fc01ef ("powerpc/32s: Implement Kernel Userspace Access Protection") > Fixes: 31ed2b13c48d ("powerpc/32s: Implement Kernel Userspace Execution Prevention.") > Cc: stable@vger.kernel.org > --- > arch/powerpc/platforms/powermac/sleep.S | 9 +-------- > 1 file changed, 1 insertion(+), 8 deletions(-) Doesn't build? pmac32_defconfig, gcc 9.3.0: ld: arch/powerpc/platforms/powermac/sleep.o: in function `core99_wake_up': (.text+0x25c): undefined reference to `load_segment_registers' Missing _GLOBAL() presumably? cheers > diff --git a/arch/powerpc/platforms/powermac/sleep.S b/arch/powerpc/platforms/powermac/sleep.S > index f9a680fdd9c4..51bfdfe85058 100644 > --- a/arch/powerpc/platforms/powermac/sleep.S > +++ b/arch/powerpc/platforms/powermac/sleep.S > @@ -294,14 +294,7 @@ grackle_wake_up: > * we do any r1 memory access as we are not sure they > * are in a sane state above the first 256Mb region > */ > - li r0,16 /* load up segment register values */ > - mtctr r0 /* for context 0 */ > - lis r3,0x2000 /* Ku = 1, VSID = 0 */ > - li r4,0 > -3: mtsrin r3,r4 > - addi r3,r3,0x111 /* increment VSID */ > - addis r4,r4,0x1000 /* address of next segment */ > - bdnz 3b > + bl load_segment_registers > sync > isync > > -- > 2.25.0