linux-kernel - Re: [PATCH] selftests/mm: remove PROT

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250910091622.n25zvgw27olskao2@master>
Date: Wed, 10 Sep 2025 09:16:22 +0000
From: Wei Yang <richard.weiyang@...il.com>
To: Zach O'Keefe <zokeefe@...gle.com>
Cc: Andrew Morton <akpm@...ux-foundation.org>,
	David Hildenbrand <david@...hat.com>,
	Lorenzo Stoakes <lorenzo.stoakes@...cle.com>,
	Zi Yan <ziy@...dia.com>,
	Baolin Wang <baolin.wang@...ux.alibaba.com>,
	"Liam R. Howlett" <Liam.Howlett@...cle.com>,
	Ryan Roberts <ryan.roberts@....com>, Dev Jain <dev.jain@....com>,
	Shuah Khan <shuah@...nel.org>, linux-mm@...ck.org,
	linux-kselftest@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] selftests/mm: remove PROT_EXEC req from file-collapse
 tests

On Tue, Sep 09, 2025 at 12:05:34PM -0700, Zach O'Keefe wrote:
>As of v6.8 commit 7fbb5e188248 ("mm: remove VM_EXEC requirement for THP eligibility")
>thp collapse no longer requires file-backed mappings be created with
>PROT_EXEC.
>

One question, what if user run this new version test on old kernel?

Is there a guideline for user?

>Remove the overly-strict dependency from thp collapse tests so we test
>the least-strict requirement for success.
>
>Signed-off-by: Zach O'Keefe <zokeefe@...gle.com>
>---
> tools/testing/selftests/mm/khugepaged.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c
>index a18c50d51141..3fe7ef04ac62 100644
>--- a/tools/testing/selftests/mm/khugepaged.c
>+++ b/tools/testing/selftests/mm/khugepaged.c
>@@ -394,7 +394,7 @@ static void *file_setup_area(int nr_hpages)
> 		perror("open()");
> 		exit(EXIT_FAILURE);
> 	}
>-	p = mmap(BASE_ADDR, size, PROT_READ | PROT_EXEC,
>+	p = mmap(BASE_ADDR, size, PROT_READ,
> 		 MAP_PRIVATE, finfo.fd, 0);
> 	if (p == MAP_FAILED || p != BASE_ADDR) {
> 		perror("mmap()");
>-- 
>2.51.0.384.g4c02a37b29-goog
>

-- 
Wei Yang
Help you, Help me