Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753326AbdGEVYs (ORCPT ); Wed, 5 Jul 2017 17:24:48 -0400 Received: from mail-qt0-f196.google.com ([209.85.216.196]:35525 "EHLO mail-qt0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753253AbdGEVYG (ORCPT ); Wed, 5 Jul 2017 17:24:06 -0400 From: Ram Pai To: 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, aneesh.kumar@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 Subject: [RFC v5 32/38] powerpc: capture the violated protection key on fault Date: Wed, 5 Jul 2017 14:22:09 -0700 Message-Id: <1499289735-14220-33-git-send-email-linuxram@us.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1499289735-14220-1-git-send-email-linuxram@us.ibm.com> References: <1499289735-14220-1-git-send-email-linuxram@us.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2423 Lines: 65 Capture the protection key that got violated in paca. This value will be used by used to inform the signal handler. Signed-off-by: Ram Pai --- arch/powerpc/include/asm/paca.h | 1 + arch/powerpc/kernel/asm-offsets.c | 1 + arch/powerpc/mm/fault.c | 3 +++ 3 files changed, 5 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h index c8bd1fc..0c06188 100644 --- a/arch/powerpc/include/asm/paca.h +++ b/arch/powerpc/include/asm/paca.h @@ -94,6 +94,7 @@ struct paca_struct { u64 dscr_default; /* per-CPU default DSCR */ #ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS u64 paca_amr; /* value of amr at exception */ + u16 paca_pkey; /* exception causing pkey */ #endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ #ifdef CONFIG_PPC_STD_MMU_64 diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 17f5d8a..7dff862 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -244,6 +244,7 @@ int main(void) #ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS OFFSET(PACA_AMR, paca_struct, paca_amr); + OFFSET(PACA_PKEY, paca_struct, paca_pkey); #endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ OFFSET(ACCOUNT_STARTTIME, paca_struct, accounting.starttime); diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index a6710f5..c8674a7 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -265,6 +265,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long address, if (error_code & DSISR_KEYFAULT) { code = SEGV_PKUERR; get_paca()->paca_amr = read_amr(); + get_paca()->paca_pkey = get_pte_pkey(current->mm, address); goto bad_area_nosemaphore; } #endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ @@ -290,6 +291,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long address, perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); + /* * We want to do this outside mmap_sem, because reading code around nip * can result in fault, which will cause a deadlock when called with @@ -453,6 +455,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long address, if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE, is_exec, 0)) { get_paca()->paca_amr = read_amr(); + get_paca()->paca_pkey = vma_pkey(vma); code = SEGV_PKUERR; goto bad_area; } -- 1.7.1