From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-x243.google.com (mail-qt0-x243.google.com [IPv6:2607:f8b0:400d:c0d::243]) (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 3zN3jF2ZWXzF0xb for ; Fri, 19 Jan 2018 12:52:01 +1100 (AEDT) Received: by mail-qt0-x243.google.com with SMTP id 33so464467qtv.1 for ; Thu, 18 Jan 2018 17:52:01 -0800 (PST) Sender: Ram Pai From: Ram Pai To: mpe@ellerman.id.au, mingo@redhat.com, akpm@linux-foundation.org, corbet@lwn.net, arnd@arndb.de Cc: linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, dave.hansen@intel.com, benh@kernel.crashing.org, paulus@samba.org, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, hbabu@us.ibm.com, mhocko@kernel.org, bauerman@linux.vnet.ibm.com, ebiederm@xmission.com, linuxram@us.ibm.com Subject: [PATCH v10 07/27] powerpc: cleanup AMR, IAMR when a key is allocated or freed Date: Thu, 18 Jan 2018 17:50:28 -0800 Message-Id: <1516326648-22775-8-git-send-email-linuxram@us.ibm.com> In-Reply-To: <1516326648-22775-1-git-send-email-linuxram@us.ibm.com> References: <1516326648-22775-1-git-send-email-linuxram@us.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cleanup the bits corresponding to a key in the AMR, and IAMR register, when the key is newly allocated/activated or is freed. We dont want some residual bits cause the hardware enforce unintended behavior when the key is activated or freed. Reviewed-by: Thiago Jung Bauermann Signed-off-by: Ram Pai --- arch/powerpc/include/asm/pkeys.h | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h index 1e8cef2..9964b46 100644 --- a/arch/powerpc/include/asm/pkeys.h +++ b/arch/powerpc/include/asm/pkeys.h @@ -69,6 +69,8 @@ static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey) __mm_pkey_is_allocated(mm, pkey)); } +extern void __arch_activate_pkey(int pkey); +extern void __arch_deactivate_pkey(int pkey); /* * Returns a positive, 5-bit key on success, or -1 on failure. * Relies on the mmap_sem to protect against concurrency in mm_pkey_alloc() and @@ -96,6 +98,12 @@ static inline int mm_pkey_alloc(struct mm_struct *mm) ret = ffz((u32)mm_pkey_allocation_map(mm)); __mm_pkey_allocated(mm, ret); + + /* + * Enable the key in the hardware + */ + if (ret > 0) + __arch_activate_pkey(ret); return ret; } @@ -107,6 +115,10 @@ static inline int mm_pkey_free(struct mm_struct *mm, int pkey) if (!mm_pkey_is_allocated(mm, pkey)) return -EINVAL; + /* + * Disable the key in the hardware + */ + __arch_deactivate_pkey(pkey); __mm_pkey_free(mm, pkey); return 0; -- 1.7.1