Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934051AbdGTGnC (ORCPT ); Thu, 20 Jul 2017 02:43:02 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:47702 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933303AbdGTGnA (ORCPT ); Thu, 20 Jul 2017 02:43:00 -0400 From: "Aneesh Kumar K.V" To: Ram Pai , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, khandual@linux.vnet.ibm.com, bsingharora@gmail.com, dave.hansen@intel.com, hbabu@us.ibm.com, linuxram@us.ibm.com, arnd@arndb.de, akpm@linux-foundation.org, corbet@lwn.net, mingo@redhat.com, mhocko@kernel.org Subject: Re: [RFC v6 27/62] powerpc: helper to validate key-access permissions of a pte In-Reply-To: <1500177424-13695-28-git-send-email-linuxram@us.ibm.com> References: <1500177424-13695-1-git-send-email-linuxram@us.ibm.com> <1500177424-13695-28-git-send-email-linuxram@us.ibm.com> Date: Thu, 20 Jul 2017 12:12:47 +0530 MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-MML: disable x-cbid: 17072006-0044-0000-0000-000002801F0E X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17072006-0045-0000-0000-00000711241B Message-Id: <87mv7zpq1k.fsf@skywalker.in.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-07-20_04:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1706020000 definitions=main-1707200108 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1941 Lines: 54 Ram Pai writes: > helper function that checks if the read/write/execute is allowed > on the pte. > > Signed-off-by: Ram Pai > --- > arch/powerpc/include/asm/book3s/64/pgtable.h | 4 +++ > arch/powerpc/include/asm/pkeys.h | 12 +++++++++ > arch/powerpc/mm/pkeys.c | 33 ++++++++++++++++++++++++++ > 3 files changed, 49 insertions(+), 0 deletions(-) > > diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h > index 30d7f55..0056e58 100644 > --- a/arch/powerpc/include/asm/book3s/64/pgtable.h > +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h > @@ -472,6 +472,10 @@ static inline void write_uamor(u64 value) > mtspr(SPRN_UAMOR, value); > } > > +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS > +extern bool arch_pte_access_permitted(u64 pte, bool write, bool execute); > +#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ > + > #define __HAVE_ARCH_PTEP_GET_AND_CLEAR > static inline pte_t ptep_get_and_clear(struct mm_struct *mm, > unsigned long addr, pte_t *ptep) > diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h > index bbb5d85..7a9aade 100644 > --- a/arch/powerpc/include/asm/pkeys.h > +++ b/arch/powerpc/include/asm/pkeys.h > @@ -53,6 +53,18 @@ static inline u64 pte_to_hpte_pkey_bits(u64 pteflags) > ((pteflags & H_PAGE_PKEY_BIT4) ? HPTE_R_KEY_BIT4 : 0x0UL)); > } > > +static inline u16 pte_to_pkey_bits(u64 pteflags) > +{ > + if (!pkey_inited) > + return 0x0UL; Do we really need that above check ? We should always find it peky_inited to be set. > + > + return (((pteflags & H_PAGE_PKEY_BIT0) ? 0x10 : 0x0UL) | > + ((pteflags & H_PAGE_PKEY_BIT1) ? 0x8 : 0x0UL) | > + ((pteflags & H_PAGE_PKEY_BIT2) ? 0x4 : 0x0UL) | > + ((pteflags & H_PAGE_PKEY_BIT3) ? 0x2 : 0x0UL) | > + ((pteflags & H_PAGE_PKEY_BIT4) ? 0x1 : 0x0UL)); > +} > + -aneesh