Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752312AbdGPEHm (ORCPT ); Sun, 16 Jul 2017 00:07:42 -0400 Received: from mail-qk0-f196.google.com ([209.85.220.196]:36195 "EHLO mail-qk0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751768AbdGPD7V (ORCPT ); Sat, 15 Jul 2017 23:59:21 -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, mhocko@kernel.org Subject: [RFC v6 32/62] powerpc: capture AMR register content on pkey violation Date: Sat, 15 Jul 2017 20:56:34 -0700 Message-Id: <1500177424-13695-33-git-send-email-linuxram@us.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1500177424-13695-1-git-send-email-linuxram@us.ibm.com> References: <1500177424-13695-1-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: 2419 Lines: 65 capture AMR register contents, and save it in paca whenever a pkey violation is detected. This value will be needed to deliver pkey-violation signal to the task. Signed-off-by: Ram Pai --- arch/powerpc/include/asm/paca.h | 3 +++ arch/powerpc/kernel/asm-offsets.c | 5 +++++ arch/powerpc/mm/fault.c | 2 ++ 3 files changed, 10 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h index 1c09f8f..c8bd1fc 100644 --- a/arch/powerpc/include/asm/paca.h +++ b/arch/powerpc/include/asm/paca.h @@ -92,6 +92,9 @@ struct paca_struct { struct dtl_entry *dispatch_log_end; #endif /* CONFIG_PPC_STD_MMU_64 */ u64 dscr_default; /* per-CPU default DSCR */ +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS + u64 paca_amr; /* value of amr at exception */ +#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 709e234..17f5d8a 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -241,6 +241,11 @@ int main(void) OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id); OFFSET(PACAKEXECSTATE, paca_struct, kexec_state); OFFSET(PACA_DSCR_DEFAULT, paca_struct, dscr_default); + +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS + OFFSET(PACA_AMR, paca_struct, paca_amr); +#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ + OFFSET(ACCOUNT_STARTTIME, paca_struct, accounting.starttime); OFFSET(ACCOUNT_STARTTIME_USER, paca_struct, accounting.starttime_user); OFFSET(ACCOUNT_USER_TIME, paca_struct, accounting.utime); diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index ea74fe2..a6710f5 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -264,6 +264,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long address, #ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS if (error_code & DSISR_KEYFAULT) { code = SEGV_PKUERR; + get_paca()->paca_amr = read_amr(); goto bad_area_nosemaphore; } #endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ @@ -451,6 +452,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long address, #ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE, is_exec, 0)) { + get_paca()->paca_amr = read_amr(); code = SEGV_PKUERR; goto bad_area; } -- 1.7.1