From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-x241.google.com (mail-pg0-x241.google.com [IPv6:2607:f8b0:400e:c05::241]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3xt3xY3QdZzDqlR for ; Thu, 14 Sep 2017 13:32:17 +1000 (AEST) Received: by mail-pg0-x241.google.com with SMTP id v82so1051654pgb.1 for ; Wed, 13 Sep 2017 20:32:17 -0700 (PDT) Date: Thu, 14 Sep 2017 13:32:05 +1000 From: Balbir Singh To: Ram Pai Cc: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, benh@kernel.crashing.org, paulus@samba.org, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, hbabu@us.ibm.com, mhocko@kernel.org, bauerman@linux.vnet.ibm.com, ebiederm@xmission.com Subject: Re: [PATCH 01/25] powerpc: initial pkey plumbing Message-ID: <20170914133205.5542e70b@firefly.ozlabs.ibm.com> In-Reply-To: <1504910713-7094-10-git-send-email-linuxram@us.ibm.com> References: <1504910713-7094-1-git-send-email-linuxram@us.ibm.com> <1504910713-7094-10-git-send-email-linuxram@us.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 8 Sep 2017 15:44:49 -0700 Ram Pai wrote: > Basic plumbing to initialize the pkey system. > Nothing is enabled yet. A later patch will enable it > ones all the infrastructure is in place. > > Signed-off-by: Ram Pai > --- > arch/powerpc/Kconfig | 16 +++++++++++ > arch/powerpc/include/asm/mmu_context.h | 5 +++ > arch/powerpc/include/asm/pkeys.h | 45 ++++++++++++++++++++++++++++++++ > arch/powerpc/kernel/setup_64.c | 4 +++ > arch/powerpc/mm/Makefile | 1 + > arch/powerpc/mm/hash_utils_64.c | 1 + > arch/powerpc/mm/pkeys.c | 33 +++++++++++++++++++++++ > 7 files changed, 105 insertions(+), 0 deletions(-) > create mode 100644 arch/powerpc/include/asm/pkeys.h > create mode 100644 arch/powerpc/mm/pkeys.c > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 9fc3c0b..a4cd210 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -864,6 +864,22 @@ config SECCOMP > > If unsure, say Y. Only embedded should say N here. > > +config PPC64_MEMORY_PROTECTION_KEYS > + prompt "PowerPC Memory Protection Keys" > + def_bool y > + # Note: only available in 64-bit mode > + depends on PPC64 This is not sufficient right, you need PPC_BOOK3S_64 for compile time at-least? > + select ARCH_USES_HIGH_VMA_FLAGS > + select ARCH_HAS_PKEYS > + ---help--- > + Memory Protection Keys provides a mechanism for enforcing > + page-based protections, but without requiring modification of the > + page tables when an application changes protection domains. > + > + For details, see Documentation/vm/protection-keys.txt > + > + If unsure, say y. > + > endmenu > > config ISA_DMA_API > diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h > index 3095925..7badf29 100644 > --- a/arch/powerpc/include/asm/mmu_context.h > +++ b/arch/powerpc/include/asm/mmu_context.h > @@ -141,5 +141,10 @@ static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, > /* by default, allow everything */ > return true; > } > + > +#ifndef CONFIG_PPC64_MEMORY_PROTECTION_KEYS > +#define pkey_initialize() > +#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ > + > #endif /* __KERNEL__ */ > #endif /* __ASM_POWERPC_MMU_CONTEXT_H */ > diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h > new file mode 100644 > index 0000000..c02305a > --- /dev/null > +++ b/arch/powerpc/include/asm/pkeys.h > @@ -0,0 +1,45 @@ > +#ifndef _ASM_PPC64_PKEYS_H > +#define _ASM_PPC64_PKEYS_H > + > +extern bool pkey_inited; > +extern bool pkey_execute_disable_support; > +#define ARCH_VM_PKEY_FLAGS 0 > + > +static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey) > +{ > + return (pkey == 0); > +} > + > +static inline int mm_pkey_alloc(struct mm_struct *mm) > +{ > + return -1; > +} > + > +static inline int mm_pkey_free(struct mm_struct *mm, int pkey) > +{ > + return -EINVAL; > +} > + > +/* > + * Try to dedicate one of the protection keys to be used as an > + * execute-only protection key. > + */ > +static inline int execute_only_pkey(struct mm_struct *mm) > +{ > + return 0; > +} > + > +static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma, > + int prot, int pkey) > +{ > + return 0; > +} > + > +static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, > + unsigned long init_val) > +{ > + return 0; > +} > + > +extern void pkey_initialize(void); > +#endif /*_ASM_PPC64_PKEYS_H */ > diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c > index b89c6aa..3b67014 100644 > --- a/arch/powerpc/kernel/setup_64.c > +++ b/arch/powerpc/kernel/setup_64.c > @@ -37,6 +37,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -316,6 +317,9 @@ void __init early_setup(unsigned long dt_ptr) > /* Initialize the hash table or TLB handling */ > early_init_mmu(); > > + /* initialize the key subsystem */ > + pkey_initialize(); > + > /* > * At this point, we can let interrupts switch to virtual mode > * (the MMU has been setup), so adjust the MSR in the PACA to > diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile > index fb844d2..927620a 100644 > --- a/arch/powerpc/mm/Makefile > +++ b/arch/powerpc/mm/Makefile > @@ -43,3 +43,4 @@ obj-$(CONFIG_PPC_COPRO_BASE) += copro_fault.o > obj-$(CONFIG_SPAPR_TCE_IOMMU) += mmu_context_iommu.o > obj-$(CONFIG_PPC_PTDUMP) += dump_linuxpagetables.o > obj-$(CONFIG_PPC_HTDUMP) += dump_hashpagetable.o > +obj-$(CONFIG_PPC64_MEMORY_PROTECTION_KEYS) += pkeys.o > diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c > index 0dff57b..67f62b5 100644 > --- a/arch/powerpc/mm/hash_utils_64.c > +++ b/arch/powerpc/mm/hash_utils_64.c > @@ -35,6 +35,7 @@ > #include > #include > #include > +#include > > #include > #include > diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c > new file mode 100644 > index 0000000..418a05b > --- /dev/null > +++ b/arch/powerpc/mm/pkeys.c > @@ -0,0 +1,33 @@ > +/* > + * PowerPC Memory Protection Keys management > + * Copyright (c) 2015, Intel Corporation. > + * Copyright (c) 2017, IBM Corporation. > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope it will be useful, but WITHOUT > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for > + * more details. > + */ > +#include /* PKEY_* */ > + > +bool pkey_inited; > +bool pkey_execute_disable_support; > + > +void __init pkey_initialize(void) > +{ > + /* disable the pkey system till everything > + * is in place. A patch further down the > + * line will enable it. > + */ Comment style is broken > + pkey_inited = false; > + > + /* > + * disable execute_disable support for now. > + * A patch further down will enable it. > + */ > + pkey_execute_disable_support = false; > +} Balbir Singh.