From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id B2EC36B0024 for ; Mon, 26 Mar 2018 13:29:46 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id q6so9745475pgv.12 for ; Mon, 26 Mar 2018 10:29:46 -0700 (PDT) Received: from mga09.intel.com (mga09.intel.com. [134.134.136.24]) by mx.google.com with ESMTPS id az8-v6si6273391plb.665.2018.03.26.10.29.45 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Mar 2018 10:29:45 -0700 (PDT) Subject: [PATCH 7/9] x86, pkeys, selftests: factor out "instruction page" From: Dave Hansen Date: Mon, 26 Mar 2018 10:27:31 -0700 References: <20180326172721.D5B2CBB4@viggo.jf.intel.com> In-Reply-To: <20180326172721.D5B2CBB4@viggo.jf.intel.com> Message-Id: <20180326172731.10725AC5@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 2018-03-26 10:22:37.012170189 -0700 +++ b/tools/testing/selftests/x86/protection_keys.c 2018-03-26 10:22:37.015170189 -0700 @@ -1277,12 +1277,9 @@ 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); @@ -1292,7 +1289,23 @@ 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); _