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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 820A2C55189 for ; Wed, 22 Apr 2020 10:51:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5BDA720774 for ; Wed, 22 Apr 2020 10:51:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587552663; bh=zyPS6kOD0ZGSj23nfYcTdMdRa2bkl3iBr+TWjFANl3I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=dbGJ7Dq7N3GeIe80XeMaLD108rzgY+WnsIW2uNTJwWU4m8XKqX+isAec1R9xlGAyI ryXhYntU6vdi5dKEC4nLWUxGlc/outbB85oA8yMCrwYZrUBZm8A39ZTU1/zgSynvJV sa1Vy0c229RJhLGzlv0Z8qXGGVz+EBLguoD7FMp0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726848AbgDVKu7 (ORCPT ); Wed, 22 Apr 2020 06:50:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:43762 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728702AbgDVKLf (ORCPT ); Wed, 22 Apr 2020 06:11:35 -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 A444D20575; Wed, 22 Apr 2020 10:11:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550295; bh=zyPS6kOD0ZGSj23nfYcTdMdRa2bkl3iBr+TWjFANl3I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2TbnEjv69cOTdcld8eo9CI2+97gcILFIuMn68YC221pyzBX3+jaaE1ZcWYt7gMqKl x8Ev4a1aujBEynqv+Gf2JrzQ6QNQUSfL+gEOi6s5ySpbi1nwLqUTuwFK98zJJ9ajBY fzLXiaE45uwHX34PONRpeH0gwR45Fb4YAs9DrDJk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Ellerman , Andrew Donnellan Subject: [PATCH 4.14 087/199] powerpc/powernv/idle: Restore AMR/UAMOR/AMOR after idle Date: Wed, 22 Apr 2020 11:56:53 +0200 Message-Id: <20200422095106.805295217@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095057.806111593@linuxfoundation.org> References: <20200422095057.806111593@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Michael Ellerman commit 53a712bae5dd919521a58d7bad773b949358add0 upstream. In order to implement KUAP (Kernel Userspace Access Protection) on Power9 we will be using the AMR, and therefore indirectly the UAMOR/AMOR. So save/restore these regs in the idle code. Signed-off-by: Michael Ellerman [ajd: Backport to 4.14 tree, CVE-2020-11669] Signed-off-by: Andrew Donnellan Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/idle_book3s.S | 27 +++++++++++++++++++++++---- 1 file changed, 23 insertions(+), 4 deletions(-) --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -163,8 +163,11 @@ core_idle_lock_held: bne- core_idle_lock_held blr -/* Reuse an unused pt_regs slot for IAMR */ +/* Reuse some unused pt_regs slots for AMR/IAMR/UAMOR/UAMOR */ +#define PNV_POWERSAVE_AMR _TRAP #define PNV_POWERSAVE_IAMR _DAR +#define PNV_POWERSAVE_UAMOR _DSISR +#define PNV_POWERSAVE_AMOR RESULT /* * Pass requested state in r3: @@ -198,8 +201,16 @@ pnv_powersave_common: SAVE_NVGPRS(r1) BEGIN_FTR_SECTION + mfspr r4, SPRN_AMR mfspr r5, SPRN_IAMR + mfspr r6, SPRN_UAMOR + std r4, PNV_POWERSAVE_AMR(r1) std r5, PNV_POWERSAVE_IAMR(r1) + std r6, PNV_POWERSAVE_UAMOR(r1) +BEGIN_FTR_SECTION_NESTED(42) + mfspr r7, SPRN_AMOR + std r7, PNV_POWERSAVE_AMOR(r1) +END_FTR_SECTION_NESTED_IFSET(CPU_FTR_HVMODE, 42) END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) mfcr r5 @@ -951,12 +962,20 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE) REST_GPR(2, r1) BEGIN_FTR_SECTION - /* IAMR was saved in pnv_powersave_common() */ + /* These regs were saved in pnv_powersave_common() */ + ld r4, PNV_POWERSAVE_AMR(r1) ld r5, PNV_POWERSAVE_IAMR(r1) + ld r6, PNV_POWERSAVE_UAMOR(r1) + mtspr SPRN_AMR, r4 mtspr SPRN_IAMR, r5 + mtspr SPRN_UAMOR, r6 +BEGIN_FTR_SECTION_NESTED(42) + ld r7, PNV_POWERSAVE_AMOR(r1) + mtspr SPRN_AMOR, r7 +END_FTR_SECTION_NESTED_IFSET(CPU_FTR_HVMODE, 42) /* - * We don't need an isync here because the upcoming mtmsrd is - * execution synchronizing. + * We don't need an isync here after restoring IAMR because the upcoming + * mtmsrd is execution synchronizing. */ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)