From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id 6DF9E6B0543 for ; Wed, 9 May 2018 13:18:54 -0400 (EDT) Received: by mail-pf0-f198.google.com with SMTP id x21so9816008pfn.23 for ; Wed, 09 May 2018 10:18:54 -0700 (PDT) Received: from mga06.intel.com (mga06.intel.com. [134.134.136.31]) by mx.google.com with ESMTPS id l22-v6si21891155pgn.74.2018.05.09.10.18.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 May 2018 10:18:53 -0700 (PDT) Subject: [PATCH 06/13] x86/pkeys/selftests: Factor out "instruction page" From: Dave Hansen Date: Wed, 09 May 2018 10:13:47 -0700 References: <20180509171336.76636D88@viggo.jf.intel.com> In-Reply-To: <20180509171336.76636D88@viggo.jf.intel.com> Message-Id: <20180509171347.C64AB733@viggo.jf.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, Dave Hansen , linuxram@us.ibm.com, tglx@linutronix.de, dave.hansen@intel.com, mpe@ellerman.id.au, mingo@kernel.org, akpm@linux-foundation.org, shuah@kernel.org From: Dave Hansen We currently have an execute-only test, but it is for the explicit mprotect_pkey() interface. We will soon add a test for the implicit mprotect(PROT_EXEC) enterface. We need this code in both tests. Signed-off-by: Dave Hansen Cc: Ram Pai Cc: Thomas Gleixner Cc: Dave Hansen Cc: Michael Ellermen Cc: Ingo Molnar Cc: Andrew Morton Cc: Shuah Khan --- b/tools/testing/selftests/x86/protection_keys.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff -puN tools/testing/selftests/x86/protection_keys.c~pkeys-selftests-get_pointer_to_instructions tools/testing/selftests/x86/protection_keys.c --- a/tools/testing/selftests/x86/protection_keys.c~pkeys-selftests-get_pointer_to_instructions 2018-05-09 09:20:20.764698402 -0700 +++ b/tools/testing/selftests/x86/protection_keys.c 2018-05-09 09:20:20.767698402 -0700 @@ -1238,12 +1238,9 @@ void test_ptrace_of_child(int *ptr, u16 free(plain_ptr_unaligned); } -void test_executing_on_unreadable_memory(int *ptr, u16 pkey) +void *get_pointer_to_instructions(void) { void *p1; - int scratch; - int ptr_contents; - int ret; p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE); dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write); @@ -1253,7 +1250,23 @@ void test_executing_on_unreadable_memory /* Point 'p1' at the *second* page of the function: */ p1 += PAGE_SIZE; + /* + * Try to ensure we fault this in on next touch to ensure + * we get an instruction fault as opposed to a data one + */ madvise(p1, PAGE_SIZE, MADV_DONTNEED); + + return p1; +} + +void test_executing_on_unreadable_memory(int *ptr, u16 pkey) +{ + void *p1; + int scratch; + int ptr_contents; + int ret; + + p1 = get_pointer_to_instructions(); lots_o_noops_around_write(&scratch); ptr_contents = read_ptr(p1); dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents); _