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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 08B9FC63697 for ; Thu, 22 Oct 2020 22:27:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7AFE624631 for ; Thu, 22 Oct 2020 22:27:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7AFE624631 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 341C86B0068; Thu, 22 Oct 2020 18:27:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 22FE26B006C; Thu, 22 Oct 2020 18:27:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ED5FB6B006E; Thu, 22 Oct 2020 18:27:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0088.hostedemail.com [216.40.44.88]) by kanga.kvack.org (Postfix) with ESMTP id BB6486B0068 for ; Thu, 22 Oct 2020 18:27:17 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 65A918AC3E30 for ; Thu, 22 Oct 2020 22:27:17 +0000 (UTC) X-FDA: 77400998514.18.hat55_3315e6627254 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin18.hostedemail.com (Postfix) with ESMTP id 322D41020AC25 for ; Thu, 22 Oct 2020 22:27:17 +0000 (UTC) X-HE-Tag: hat55_3315e6627254 X-Filterd-Recvd-Size: 5394 Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by imf12.hostedemail.com (Postfix) with ESMTP for ; Thu, 22 Oct 2020 22:27:15 +0000 (UTC) IronPort-SDR: E0xT8EKB5vK7SJpSFHhZlWJ9x81uDwTERmhiLjZXR2PuMOgvugwpqTwwb9BLMLQPHgGE3SyZBE Z2AXUoA86xlg== X-IronPort-AV: E=McAfee;i="6000,8403,9782"; a="229236852" X-IronPort-AV: E=Sophos;i="5.77,404,1596524400"; d="scan'208";a="229236852" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Oct 2020 15:27:13 -0700 IronPort-SDR: PgEON2dSDjhDgwJHX+QIzzPzwQILf6lmaeDrRVmCBuAgdJLZXquxiF992pN86zPkmZ3YD0ncVk vrUzZfm9e8uQ== X-IronPort-AV: E=Sophos;i="5.77,404,1596524400"; d="scan'208";a="524442538" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Oct 2020 15:27:13 -0700 From: ira.weiny@intel.com To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski , Peter Zijlstra Cc: Ira Weiny , x86@kernel.org, Dave Hansen , Dan Williams , Andrew Morton , Fenghua Yu , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Subject: [PATCH 02/10] x86/fpu: Refactor arch_set_user_pkey_access() for PKS support Date: Thu, 22 Oct 2020 15:26:53 -0700 Message-Id: <20201022222701.887660-3-ira.weiny@intel.com> X-Mailer: git-send-email 2.28.0.rc0.12.gb6a658bd00c9 In-Reply-To: <20201022222701.887660-1-ira.weiny@intel.com> References: <20201022222701.887660-1-ira.weiny@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Ira Weiny Define a helper, update_pkey_val(), which will be used to support both Protection Key User (PKU) and the new Protection Key for Supervisor (PKS) in subsequent patches. Co-developed-by: Peter Zijlstra Signed-off-by: Peter Zijlstra Signed-off-by: Ira Weiny --- Changes from RFC V3: Per Dave Hansen Update and add comments per Dave's review Per Peter Correct attribution --- arch/x86/include/asm/pkeys.h | 2 ++ arch/x86/kernel/fpu/xstate.c | 22 ++++------------------ arch/x86/mm/pkeys.c | 23 +++++++++++++++++++++++ 3 files changed, 29 insertions(+), 18 deletions(-) diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h index f9feba80894b..4526245b03e5 100644 --- a/arch/x86/include/asm/pkeys.h +++ b/arch/x86/include/asm/pkeys.h @@ -136,4 +136,6 @@ static inline int vma_pkey(struct vm_area_struct *vma= ) return (vma->vm_flags & vma_pkey_mask) >> VM_PKEY_SHIFT; } =20 +u32 update_pkey_val(u32 pk_reg, int pkey, unsigned int flags); + #endif /*_ASM_X86_PKEYS_H */ diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index a99afc70cc0a..a3bca3211eba 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -994,9 +994,7 @@ const void *get_xsave_field_ptr(int xfeature_nr) int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, unsigned long init_val) { - u32 old_pkru; - int pkey_shift =3D (pkey * PKR_BITS_PER_PKEY); - u32 new_pkru_bits =3D 0; + u32 pkru; =20 /* * This check implies XSAVE support. OSPKE only gets @@ -1012,21 +1010,9 @@ int arch_set_user_pkey_access(struct task_struct *= tsk, int pkey, */ WARN_ON_ONCE(pkey >=3D arch_max_pkey()); =20 - /* Set the bits we need in PKRU: */ - if (init_val & PKEY_DISABLE_ACCESS) - new_pkru_bits |=3D PKR_AD_BIT; - if (init_val & PKEY_DISABLE_WRITE) - new_pkru_bits |=3D PKR_WD_BIT; - - /* Shift the bits in to the correct place in PKRU for pkey: */ - new_pkru_bits <<=3D pkey_shift; - - /* Get old PKRU and mask off any old bits in place: */ - old_pkru =3D read_pkru(); - old_pkru &=3D ~((PKR_AD_BIT|PKR_WD_BIT) << pkey_shift); - - /* Write old part along with new part: */ - write_pkru(old_pkru | new_pkru_bits); + pkru =3D read_pkru(); + pkru =3D update_pkey_val(pkru, pkey, init_val); + write_pkru(pkru); =20 return 0; } diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c index f5efb4007e74..d1dfe743e79f 100644 --- a/arch/x86/mm/pkeys.c +++ b/arch/x86/mm/pkeys.c @@ -208,3 +208,26 @@ static __init int setup_init_pkru(char *opt) return 1; } __setup("init_pkru=3D", setup_init_pkru); + +/* + * Replace disable bits for @pkey with values from @flags + * + * Kernel users use the same flags as user space: + * PKEY_DISABLE_ACCESS + * PKEY_DISABLE_WRITE + */ +u32 update_pkey_val(u32 pk_reg, int pkey, unsigned int flags) +{ + int pkey_shift =3D pkey * PKR_BITS_PER_PKEY; + + /* Mask out old bit values */ + pk_reg &=3D ~(((1 << PKR_BITS_PER_PKEY) - 1) << pkey_shift); + + /* Or in new values */ + if (flags & PKEY_DISABLE_ACCESS) + pk_reg |=3D PKR_AD_BIT << pkey_shift; + if (flags & PKEY_DISABLE_WRITE) + pk_reg |=3D PKR_WD_BIT << pkey_shift; + + return pk_reg; +} --=20 2.28.0.rc0.12.gb6a658bd00c9