From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3BF5AEB64D7 for ; Fri, 30 Jun 2023 13:38:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232119AbjF3Ni4 (ORCPT ); Fri, 30 Jun 2023 09:38:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54492 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230506AbjF3Niy (ORCPT ); Fri, 30 Jun 2023 09:38:54 -0400 Received: from bg4.exmail.qq.com (bg4.exmail.qq.com [43.155.65.254]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 811BC1FE8; Fri, 30 Jun 2023 06:38:52 -0700 (PDT) X-QQ-mid: bizesmtp72t1688132308t5lpes6w Received: from linux-lab-host.localdomain ( [119.123.131.49]) by bizesmtp.qq.com (ESMTP) with id ; Fri, 30 Jun 2023 21:38:27 +0800 (CST) X-QQ-SSF: 01200000000000D0W000000A0000000 X-QQ-FEAT: G+WLZ/1vSOE/QeI/ppaBpcBNTobcOzk/g+2a/fUhWadeWAN+Bf2pPc5KJQ0qu voSj4wbaCgh1sL5WZn80GZweZDDv0HyR/15Km1SmhfByZvoLY8ZUEIFopcm4HQoEA6UX4ZH t8q9lQ5IwoPbm+PPSMuTROK2wA7dH7g+p0MWNA9tXIAfcqqhXmQheuhxTN6yvNrJEXakTbJ L986E2QHyLUolLKqSvg3ID/S1QVbiu0NyS/unPrW1XC+2lWzzKtzBj7VB9+og4kdNRHJL9N 0r1UDRFNLOuXKr0uS1P4VPKZje/L5VnJ5ZrmSZ6VKBU0pQaENlncL4aoXOdcf5Itm4Og3Yz O9oTPAv7rIx2XYBpdhXS58MK7GPO3KO7MVrWKretIXL59pJhBYmGlgpTdc9kJl3aYmvUyXB X-QQ-GoodBg: 0 X-BIZMAIL-ID: 4867400409169338334 From: Zhangjin Wu To: linux@weissschuh.net Cc: akpm@linux-foundation.org, brauner@kernel.org, falcon@tinylab.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, w@lwt.eu Subject: Re: [PATCH] mm: make MEMFD_CREATE into a selectable config option Date: Fri, 30 Jun 2023 21:38:26 +0800 Message-Id: <20230630133826.245610-1-falcon@tinylab.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230630-config-memfd-v1-1-9acc3ae38b5a@weissschuh.net> References: <20230630-config-memfd-v1-1-9acc3ae38b5a@weissschuh.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:tinylab.org:qybglogicsvrgz:qybglogicsvrgz5a-1 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hi, Thomas I have manually applied your patch on v6.4, enabled MEMFD_CREATE (and disabled TMPFS and HUGETLBFS) for 3 randomly selected virtual boards: - arm/vexpress-a9 - aarch64/virt - mipsel/malta For all of the above boards, the current vfprintf test (uses memfd_create) of tools/testing/selftests/nolibc/nolibc-test.c passes without any failure: Running test 'vfprintf' 0 emptymemfd_create() without MFD_EXEC nor MFD_NOEXEC_SEAL, pid=1 'init' "" = "" [OK] 1 simple "foo" = "foo" [OK] 2 string "foo" = "foo" [OK] 3 number "1234" = "1234" [OK] 4 negnumber "-1234" = "-1234" [OK] 5 unsigned "12345" = "12345" [OK] 6 char "c" = "c" [OK] 7 hex "f" = "f" [OK] 8 pointer "0x1" = "0x1" [OK] Errors during this test: 0 If this test result is ok for you, here is my: Tested-by: Zhangjin Wu Best regards, Zhangjin > > The memfd_create() syscall, enabled by CONFIG_MEMFD_CREATE, is useful on > its own even when not required by CONFIG_TMPFS or CONFIG_HUGETLBFS. > > Split it into its own proper bool option that can be enabled by users. > > Move that option into mm/ where the code itself also lies. > Also add "select" statements to CONFIG_TMPFS and CONFIG_HUGETLBFS so > they automatically enable CONFIG_MEMFD_CREATE as before. > > Signed-off-by: Thomas Weißschuh > --- > fs/Kconfig | 5 ++--- > mm/Kconfig | 3 +++ > 2 files changed, 5 insertions(+), 3 deletions(-) > > diff --git a/fs/Kconfig b/fs/Kconfig > index 18d034ec7953..19975b104bc3 100644 > --- a/fs/Kconfig > +++ b/fs/Kconfig > @@ -169,6 +169,7 @@ source "fs/sysfs/Kconfig" > config TMPFS > bool "Tmpfs virtual memory file system support (former shm fs)" > depends on SHMEM > + select MEMFD_CREATE > help > Tmpfs is a file system which keeps all files in virtual memory. > > @@ -240,6 +241,7 @@ config HUGETLBFS > bool "HugeTLB file system support" > depends on X86 || IA64 || SPARC64 || ARCH_SUPPORTS_HUGETLBFS || BROKEN > depends on (SYSFS || SYSCTL) > + select MEMFD_CREATE > help > hugetlbfs is a filesystem backing for HugeTLB pages, based on > ramfs. For architectures that support it, say Y here and read > @@ -264,9 +266,6 @@ config HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON > enable HVO by default. It can be disabled via hugetlb_free_vmemmap=off > (boot command line) or hugetlb_optimize_vmemmap (sysctl). > > -config MEMFD_CREATE > - def_bool TMPFS || HUGETLBFS > - > config ARCH_HAS_GIGANTIC_PAGE > bool > > diff --git a/mm/Kconfig b/mm/Kconfig > index 09130434e30d..22acffd9009d 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -1144,6 +1144,9 @@ config KMAP_LOCAL_NON_LINEAR_PTE_ARRAY > config IO_MAPPING > bool > > +config MEMFD_CREATE > + bool "Enable memfd_create() system call" if EXPERT > + > config SECRETMEM > default y > bool "Enable memfd_secret() system call" if EXPERT > > --- > base-commit: e55e5df193d247a38a5e1ac65a5316a0adcc22fa > change-id: 20230629-config-memfd-be6af03b7dca > > Best regards, > -- > Thomas Weißschuh >