From nobody Sun Feb 8 09:27:29 2026 Received: from pdx-out-006.esa.us-west-2.outbound.mail-perimeter.amazon.com (pdx-out-006.esa.us-west-2.outbound.mail-perimeter.amazon.com [52.26.1.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6B2AD255F24; Wed, 8 Oct 2025 12:54:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=52.26.1.71 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759928087; cv=none; b=I/MJZ7c+R4fRxb8aLyKnszMEok3QXdjlc3O08nKO7c4Q0+hNhL41d+7KRJ1xuZcVzgdlXCb/Muj9EP8GV8Hfx93SGlkUzt5vtGyWcqgIRbBb6gq0AP6Gh1LDQj/eUbJdHTiZZdleniKx9BbdQRzOvVZjCzlQRG2HxDwkKxmLGLg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759928087; c=relaxed/simple; bh=W6Su0zvUbKBAp5gS50zGnBYp1oJrGt5PJf150nAFsZA=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=O9khK1GTGKfwbnx92ifCNjgFNCjoVu2Iu27wY8dulBSIyfLJtxvXBe/ruI4Tf7YxdnHh0U4EDpjP1ETU/j0tJU56e7Kx9VUbAqF/MXEefdtdbP6tJK8d463TsPl8tsk4qMF4c2Nrest6GMgjdFS0J8XdtC2Lep9bmkmA/8jM8EM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.de; spf=pass smtp.mailfrom=amazon.de; dkim=pass (2048-bit key) header.d=amazon.de header.i=@amazon.de header.b=DnnZ3dTE; arc=none smtp.client-ip=52.26.1.71 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amazon.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=amazon.de header.i=@amazon.de header.b="DnnZ3dTE" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.de; i=@amazon.de; q=dns/txt; s=amazoncorp2; t=1759928085; x=1791464085; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ZRDeMLmMEK6yn6l4ewtwCCdRu9Khsl3Xp6VISO2xrwE=; b=DnnZ3dTEGpdhw0VpHnsQ6pznJoFd4kb+WzApsNXLaVYSBiwlamsffoif +3v1OS3jUuh9toJMAOFqwZjOjysqr58m8YRXOw2b01DsvzVn9Bvrr3z5o ELeS9mP1wIYqIrO/vlNlfL5k01hgVjxA8/hq8Qe8NgR6hWw4TKbwWrE1k YR43BoyuZDddc+9zcNhXLPQZeJ5zzBeLuLaftgeCCIZ5rvcLHi2E0V/AY DVWUfsPzrN1KFGQj+vn7Xk91GlV+bjPjNrkbHwFOzesFEgXTzX5k0KvtX mqGShV4UUZtSNnlK0lv006yzZQ/++GptZEGYGQEZakViiH6Oh5v/BPRfs Q==; X-CSE-ConnectionGUID: mLsNYFOJRhSzPy7GhW1xEw== X-CSE-MsgGUID: Jm0hr+PXQjSTK4ngOiWpag== X-IronPort-AV: E=Sophos;i="6.18,281,1751241600"; d="scan'208";a="4518957" Received: from ip-10-5-12-219.us-west-2.compute.internal (HELO smtpout.naws.us-west-2.prod.farcaster.email.amazon.dev) ([10.5.12.219]) by internal-pdx-out-006.esa.us-west-2.outbound.mail-perimeter.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Oct 2025 12:54:43 +0000 Received: from EX19MTAUWC002.ant.amazon.com [10.0.21.151:27609] by smtpin.naws.us-west-2.prod.farcaster.email.amazon.dev [10.0.20.71:2525] with esmtp (Farcaster) id 1b53c0ac-769c-46a7-ba29-79ccaadef900; Wed, 8 Oct 2025 12:54:43 +0000 (UTC) X-Farcaster-Flow-ID: 1b53c0ac-769c-46a7-ba29-79ccaadef900 Received: from EX19D001UWA001.ant.amazon.com (10.13.138.214) by EX19MTAUWC002.ant.amazon.com (10.250.64.143) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.20; Wed, 8 Oct 2025 12:54:42 +0000 Received: from dev-dsk-acsjakub-1b-6f9934e2.eu-west-1.amazon.com (172.19.75.107) by EX19D001UWA001.ant.amazon.com (10.13.138.214) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.20; Wed, 8 Oct 2025 12:54:40 +0000 From: Jakub Acs To: , CC: , , , , , , , , , , , Subject: [PATCH] mm: use enum for vm_flags Date: Wed, 8 Oct 2025 12:54:27 +0000 Message-ID: <20251008125427.68735-1-acsjakub@amazon.de> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251007162136.1885546-1-aliceryhl@google.com> References: <20251007162136.1885546-1-aliceryhl@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: EX19D041UWB003.ant.amazon.com (10.13.139.176) To EX19D001UWA001.ant.amazon.com (10.13.138.214) Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" redefine VM_* flag constants with BIT() Make VM_* flag constant definitions consistent - unify all to use BIT() macro and define them within an enum. The bindgen tool is better able to handle BIT(_) declarations when used in an enum. Also add enum definitions for tracepoints. We have previously changed VM_MERGEABLE in a separate bugfix. This is a follow-up to make all the VM_* flag constant definitions consistent, as suggested by David in [1]. [1]: https://lore.kernel.org/all/85f852f9-8577-4230-adc7-c52e7f479454@redha= t.com/ Signed-off-by: Jakub Acs Cc: Andrew Morton Cc: David Hildenbrand Cc: Xu Xin Cc: Chengming Zhou Cc: Peter Xu Cc: Axel Rasmussen Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org --- Hi Alice, thanks for the patch, I squashed it in (should I add your signed-off-by too?) and added the TRACE_DEFINE_ENUM calls pointed out by Derrick. I have the following points to still address, though:=20 - can the fact that we're not controlling the type of the values if using enum be a problem? (likely the indirect control we have through the highest value is good enough, but I'm not sure) - where do TRACE_DEFINE_ENUM calls belong? I see them placed e.g. in include/trace/misc/nfs.h for nfs or arch/x86/kvm/mmu/mmutrace.h, but I don't see a corresponding file for mm.h - does this warrant creating a separate file for these definitions? - with the need for TRACE_DEFINE_ENUM calls, do we still deem this to be a good trade-off? - isn't fixing all of these in rust/bindings/bindings_helper.h better? @Derrick, can you point me to how to test for the issue you pointed out? Thanks, Jakub include/linux/mm.h | 142 ++++++++++++++++++++++---------- rust/bindings/bindings_helper.h | 1 - 2 files changed, 98 insertions(+), 45 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 70a2a76007d4..8b9e7a9e7042 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -36,6 +36,7 @@ #include #include #include +#include =20 struct mempolicy; struct anon_vma; @@ -273,57 +274,58 @@ extern unsigned int kobjsize(const void *objp); * vm_flags in vm_area_struct, see mm_types.h. * When changing, update also include/trace/events/mmflags.h */ -#define VM_NONE 0x00000000 +enum { + VM_NONE =3D 0, =20 -#define VM_READ 0x00000001 /* currently active flags */ -#define VM_WRITE 0x00000002 -#define VM_EXEC 0x00000004 -#define VM_SHARED 0x00000008 + VM_READ =3D BIT(0), /* currently active flags */ + VM_WRITE =3D BIT(1), + VM_EXEC =3D BIT(2), + VM_SHARED =3D BIT(3), =20 /* mprotect() hardcodes VM_MAYREAD >> 4 =3D=3D VM_READ, and so for r/w/x b= its. */ -#define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */ -#define VM_MAYWRITE 0x00000020 -#define VM_MAYEXEC 0x00000040 -#define VM_MAYSHARE 0x00000080 + VM_MAYREAD =3D BIT(4), /* limits for mprotect() etc */ + VM_MAYWRITE =3D BIT(5), + VM_MAYEXEC =3D BIT(6), + VM_MAYSHARE =3D BIT(7), =20 -#define VM_GROWSDOWN 0x00000100 /* general info on the segment */ + VM_GROWSDOWN =3D BIT(8), /* general info on the segment */ #ifdef CONFIG_MMU -#define VM_UFFD_MISSING 0x00000200 /* missing pages tracking */ + VM_UFFD_MISSING =3D BIT(9), /* missing pages tracking */ #else /* CONFIG_MMU */ -#define VM_MAYOVERLAY 0x00000200 /* nommu: R/O MAP_PRIVATE mapping that mi= ght overlay a file mapping */ + VM_MAYOVERLAY =3D BIT(9), /* nommu: R/O MAP_PRIVATE mapping that might o= verlay a file mapping */ #define VM_UFFD_MISSING 0 #endif /* CONFIG_MMU */ -#define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page",= just pure PFN */ -#define VM_UFFD_WP 0x00001000 /* wrprotect pages tracking */ - -#define VM_LOCKED 0x00002000 -#define VM_IO 0x00004000 /* Memory mapped I/O or similar */ - - /* Used by sys_madvise() */ -#define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ -#define VM_RAND_READ 0x00010000 /* App will not benefit from clustered rea= ds */ - -#define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ -#define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ -#define VM_LOCKONFAULT 0x00080000 /* Lock the pages covered when they are = faulted in */ -#define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ -#define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */ -#define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ -#define VM_SYNC 0x00800000 /* Synchronous page faults */ -#define VM_ARCH_1 0x01000000 /* Architecture-specific flag */ -#define VM_WIPEONFORK 0x02000000 /* Wipe VMA contents in child. */ -#define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */ + VM_PFNMAP =3D BIT(10), /* Page-ranges managed without "struct page", jus= t pure PFN */ + VM_UFFD_WP =3D BIT(12), /* wrprotect pages tracking */ + + VM_LOCKED =3D BIT(13), + VM_IO =3D BIT(14), /* Memory mapped I/O or similar */ + + /* Used by sys_madvise() */ + VM_SEQ_READ =3D BIT(15), /* App will access data sequentially */ + VM_RAND_READ =3D BIT(16), /* App will not benefit from clustered reads */ + + VM_DONTCOPY =3D BIT(17), /* Do not copy this vma on fork */ + VM_DONTEXPAND =3D BIT(18), /* Cannot expand with mremap() */ + VM_LOCKONFAULT =3D BIT(19), /* Lock the pages covered when they are faul= ted in */ + VM_ACCOUNT =3D BIT(20), /* Is a VM accounted object */ + VM_NORESERVE =3D BIT(21), /* should the VM suppress accounting */ + VM_HUGETLB =3D BIT(22), /* Huge TLB Page VM */ + VM_SYNC =3D BIT(23), /* Synchronous page faults */ + VM_ARCH_1 =3D BIT(24), /* Architecture-specific flag */ + VM_WIPEONFORK =3D BIT(25), /* Wipe VMA contents in child. */ + VM_DONTDUMP =3D BIT(26), /* Do not include in the core dump */ =20 #ifdef CONFIG_MEM_SOFT_DIRTY -# define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */ + VM_SOFTDIRTY =3D BIT(27), /* Not soft dirty clean area */ #else # define VM_SOFTDIRTY 0 #endif =20 -#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN p= ages */ -#define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */ -#define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */ -#define VM_MERGEABLE BIT(31) /* KSM may merge identical pages */ + VM_MIXEDMAP =3D BIT(28), /* Can contain "struct page" and pure PFN pages= */ + VM_HUGEPAGE =3D BIT(29), /* MADV_HUGEPAGE marked this vma */ + VM_NOHUGEPAGE =3D BIT(30), /* MADV_NOHUGEPAGE marked this vma */ + VM_MERGEABLE =3D BIT(31), /* KSM may merge identical pages */ =20 #ifdef CONFIG_ARCH_USES_HIGH_VMA_FLAGS #define VM_HIGH_ARCH_BIT_0 32 /* bit only usable on 64-bit architectures */ @@ -333,14 +335,66 @@ extern unsigned int kobjsize(const void *objp); #define VM_HIGH_ARCH_BIT_4 36 /* bit only usable on 64-bit architectures */ #define VM_HIGH_ARCH_BIT_5 37 /* bit only usable on 64-bit architectures */ #define VM_HIGH_ARCH_BIT_6 38 /* bit only usable on 64-bit architectures */ -#define VM_HIGH_ARCH_0 BIT(VM_HIGH_ARCH_BIT_0) -#define VM_HIGH_ARCH_1 BIT(VM_HIGH_ARCH_BIT_1) -#define VM_HIGH_ARCH_2 BIT(VM_HIGH_ARCH_BIT_2) -#define VM_HIGH_ARCH_3 BIT(VM_HIGH_ARCH_BIT_3) -#define VM_HIGH_ARCH_4 BIT(VM_HIGH_ARCH_BIT_4) -#define VM_HIGH_ARCH_5 BIT(VM_HIGH_ARCH_BIT_5) -#define VM_HIGH_ARCH_6 BIT(VM_HIGH_ARCH_BIT_6) + VM_HIGH_ARCH_0 =3D BIT(VM_HIGH_ARCH_BIT_0), + VM_HIGH_ARCH_1 =3D BIT(VM_HIGH_ARCH_BIT_1), + VM_HIGH_ARCH_2 =3D BIT(VM_HIGH_ARCH_BIT_2), + VM_HIGH_ARCH_3 =3D BIT(VM_HIGH_ARCH_BIT_3), + VM_HIGH_ARCH_4 =3D BIT(VM_HIGH_ARCH_BIT_4), + VM_HIGH_ARCH_5 =3D BIT(VM_HIGH_ARCH_BIT_5), + VM_HIGH_ARCH_6 =3D BIT(VM_HIGH_ARCH_BIT_6), #endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */ +}; + +TRACE_DEFINE_ENUM(VM_NONE); +TRACE_DEFINE_ENUM(VM_READ); +TRACE_DEFINE_ENUM(VM_WRITE); +TRACE_DEFINE_ENUM(VM_EXEC); +TRACE_DEFINE_ENUM(VM_SHARED); +TRACE_DEFINE_ENUM(VM_MAYREAD); +TRACE_DEFINE_ENUM(VM_MAYWRITE); +TRACE_DEFINE_ENUM(VM_MAYEXEC); +TRACE_DEFINE_ENUM(VM_MAYSHARE); +TRACE_DEFINE_ENUM(VM_GROWSDOWN); +TRACE_DEFINE_ENUM(VM_UFFD_MISSING); + +#ifndef CONFIG_MMU +TRACE_DEFINE_ENUM(VM_MAYOVERLAY); +#endif /* CONFIG_MMU */ + +TRACE_DEFINE_ENUM(VM_PFNMAP); +TRACE_DEFINE_ENUM(VM_UFFD_WP); +TRACE_DEFINE_ENUM(VM_LOCKED); +TRACE_DEFINE_ENUM(VM_IO); +TRACE_DEFINE_ENUM(VM_SEQ_READ); +TRACE_DEFINE_ENUM(VM_RAND_READ); +TRACE_DEFINE_ENUM(VM_DONTCOPY); +TRACE_DEFINE_ENUM(VM_DONTEXPAND); +TRACE_DEFINE_ENUM(VM_LOCKONFAULT); +TRACE_DEFINE_ENUM(VM_ACCOUNT); +TRACE_DEFINE_ENUM(VM_NORESERVE); +TRACE_DEFINE_ENUM(VM_HUGETLB); +TRACE_DEFINE_ENUM(VM_SYNC); +TRACE_DEFINE_ENUM(VM_ARCH_1); +TRACE_DEFINE_ENUM(VM_WIPEONFORK); +TRACE_DEFINE_ENUM(VM_DONTDUMP); + +TRACE_DEFINE_ENUM(VM_SOFTDIRTY); + +TRACE_DEFINE_ENUM(VM_MIXEDMAP); +TRACE_DEFINE_ENUM(VM_HUGEPAGE); +TRACE_DEFINE_ENUM(VM_NOHUGEPAGE); +TRACE_DEFINE_ENUM(VM_MERGEABLE); + +#ifdef CONFIG_ARCH_USES_HIGH_VMA_FLAGS +TRACE_DEFINE_ENUM(VM_HIGH_ARCH_0); +TRACE_DEFINE_ENUM(VM_HIGH_ARCH_1); +TRACE_DEFINE_ENUM(VM_HIGH_ARCH_2); +TRACE_DEFINE_ENUM(VM_HIGH_ARCH_3); +TRACE_DEFINE_ENUM(VM_HIGH_ARCH_4); +TRACE_DEFINE_ENUM(VM_HIGH_ARCH_5); +TRACE_DEFINE_ENUM(VM_HIGH_ARCH_6); +#endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */ + =20 #ifdef CONFIG_ARCH_HAS_PKEYS # define VM_PKEY_SHIFT VM_HIGH_ARCH_BIT_0 diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helpe= r.h index 2e43c66635a2..04b75d4d01c3 100644 --- a/rust/bindings/bindings_helper.h +++ b/rust/bindings/bindings_helper.h @@ -108,7 +108,6 @@ const xa_mark_t RUST_CONST_HELPER_XA_PRESENT =3D XA_PRE= SENT; =20 const gfp_t RUST_CONST_HELPER_XA_FLAGS_ALLOC =3D XA_FLAGS_ALLOC; const gfp_t RUST_CONST_HELPER_XA_FLAGS_ALLOC1 =3D XA_FLAGS_ALLOC1; -const vm_flags_t RUST_CONST_HELPER_VM_MERGEABLE =3D VM_MERGEABLE; =20 #if IS_ENABLED(CONFIG_ANDROID_BINDER_IPC_RUST) #include "../../drivers/android/binder/rust_binder.h" --=20 2.47.3 Amazon Web Services Development Center Germany GmbH Tamara-Danz-Str. 13 10243 Berlin Geschaeftsfuehrung: Christian Schlaeger Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B Sitz: Berlin Ust-ID: DE 365 538 597