From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 0332D4F4028; Thu, 17 Sep 2026 16:40:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789663221; cv=none; b=llRM3bSGiMMfnRIn2XZOIg+SarMQvBTONiwcwJiryu+iUzOPSYQt8Z/+2miWRCP0FAKoWJ69aiF6lN8h2/K9iqXib3POCKitC3r3Ept9VZJmiOj7fmVsP6kfkKWrj6t5QU1iRN9JT7E1aM2qXnUqs55u4idgEwt0y/dGdl4Lpos= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789663221; c=relaxed/simple; bh=1OwkRdoitzoVVZDSD0YPk80a3FTuq1Ny90B/+LuQWSI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=N30YWvpZp6KC1FvCMxSSjbiC97gfiHCTmNf/IQTt67eg+WlzDKaL9VeFVrRUJx3rbTftwYMHw2IGG/vGyB9v9Fji7CwUYhpVQknPLxMiSQjLiA4OmZOi2Mz9v1WgcmPq5qEauP5RPb+rnCJEqMsDn/F9UPhvblCxDAXRk91H7yg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=f8kNHfB7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="f8kNHfB7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90C0B1F0089B; Thu, 17 Sep 2026 16:39:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789663217; bh=Hp87iN4yJBRpbFa4LvlnOFRxzQZ2BOeIpx732OhJfQ8=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=f8kNHfB7/+/M+q0XJgm0qd6G2Me9Ea4weq+5GKSRz+Py6tJq9A9pxQ04HxTQ4T0qD dYfvHynIc5oWq4j6pEQdpxDBbFiXPZury1hbeOGK7+waMOgKyaVJlV3r2ujmFpSmxk 0+IszqUIS1npntiQCclR0MP6BqoTgXW6qIq3zVOQU0pTIvWpcfE0v2gWCgV3oLPLvy SiU3+zfDjJjURjF7KURJjnu12eHOfBTMwdgJeLUYV5DbDl3NAZfcJnDULTGrTBbV0T Cp0nIzX4u9CEhTqjdYpTgSs/tCh7wULt4Ud/PeGDPXjPafaMApYzatpa0ggtFetAtM 8T/yLzQagVSWw== From: "Lorenzo Stoakes (ARM)" Date: Thu, 17 Sep 2026 17:22:43 +0100 Subject: [PATCH v3 34/40] mm: eliminate VMA_SPECIAL_FLAGS usage when hugetlb explicitly tested Precedence: bulk X-Mailing-List: linux-fbdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260917-b4-mmap-prepare-vma-flag-sanify-v3-34-4583d8a23bca@kernel.org> References: <20260917-b4-mmap-prepare-vma-flag-sanify-v3-0-4583d8a23bca@kernel.org> In-Reply-To: <20260917-b4-mmap-prepare-vma-flag-sanify-v3-0-4583d8a23bca@kernel.org> To: Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , David Hildenbrand , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonathan Corbet , Greg Kroah-Hartman , Dennis Dalessandro , Jason Gunthorpe , Leon Romanovsky , Paul Moore , Stephen Smalley , Jaroslav Kysela , Takashi Iwai , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Doug Gilbert , "James E.J. Bottomley" , "Martin K. Petersen" , Jaya Kumar , Simona Vetter , Helge Deller , Sebastian Reichel , John Hubbard , Peter Xu , Masami Hiramatsu , Oleg Nesterov , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Rik van Riel , Harry Yoo , Juri Lelli , Vincent Guittot , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Arnd Bergmann , Muchun Song , Oscar Salvador , "Matthew Wilcox (Oracle)" , Jan Kara , Marc Zyngier , Oliver Upton , Catalin Marinas , Madhavan Srinivasan , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , "David S. Miller" , Andreas Larsson , Alexander Viro , Christian Brauner , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Youngjun Park , Johannes Weiner , Qi Zheng , Shakeel Butt , Axel Rasmussen , Yuanchu Xie , Wei Xu , Chengming Zhou , Michal Hocko , Miklos Szeredi , Xu Xin Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-usb@vger.kernel.org, linux-rdma@vger.kernel.org, selinux@vger.kernel.org, linux-sound@vger.kernel.org, bpf@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, fuse-devel@lists.linux.dev, "Lorenzo Stoakes (ARM)" X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=2543; i=ljs@kernel.org; h=from:subject:message-id; bh=1OwkRdoitzoVVZDSD0YPk80a3FTuq1Ny90B/+LuQWSI=; b=owGbwMvMwCV2fu7ZrsZH9SKMp9WSGLLWCB/5dYQz2lDzYVH6h4zYraVX05oT89csutLPH8yWk OLL0ufVUcrCIMbFICumyPL8i/j+IJGweZ0X/N1g5rAygQxh4OIUgIkYszEyXBJz3bX41vo9pa98 eT52f2b+62Hh8vH5ob8Pyv4khFvKGTAy/DJ6m3dxzp3ibTMnzLlRueX8uVNOltybZuwXrz+fUrO dgQEA X-Developer-Key: i=ljs@kernel.org; a=openpgp; fpr=E7F417BF5214569E89D04F46CF9DCD8A81E27F14 It is now an invariant that VMA_IO_BIT is not set except by kernel-owned mappings, so each existing VMA_SPECIAL_FLAGS test need only test for VMA_DONTEXPAND_BIT, VMA_PFNMAP_BIT and VMA_MIXEDMAP_BIT. This is precisely a test for a kernel-owned or fixed mapping. Update a number of callsites which already explicitly handle hugetlb mappings. vma_supports_mlock() and ksm_compatible() also explicitly bail on droppable mappings - detecting kernel-owned, fixed or droppable mappings is handled by vma_is_persistent(), so in these cases use this predicate. should_skip_vma() tests for locked, kernel-owned or fixed memory (having already excluded hugetlb mappings) so simply test for those there. No functional change intended. Signed-off-by: Lorenzo Stoakes (ARM) --- mm/internal.h | 4 +--- mm/ksm.c | 4 +--- mm/vmscan.c | 3 ++- 3 files changed, 4 insertions(+), 7 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index 69a6e9850960..a673fa73df03 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1113,9 +1113,7 @@ static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, static inline bool vma_supports_mlock(const struct vm_area_struct *vma) { - if (vma_test_any_mask(vma, VMA_SPECIAL_FLAGS)) - return false; - if (vma_test_single_mask(vma, VMA_DROPPABLE)) + if (!vma_is_persistent(vma)) return false; if (vma_is_dax(vma) || vma_is_hugetlb(vma)) return false; diff --git a/mm/ksm.c b/mm/ksm.c index 624f37975e12..f80372bfd4b2 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -747,9 +747,7 @@ static bool ksm_compatible(const struct file *file, vma_flags_t vma_flags) if (vma_flags_test_any(&vma_flags, VMA_SHARED_BIT, VMA_MAYSHARE_BIT, VMA_HUGETLB_BIT)) return false; - if (vma_flags_test_single_mask(&vma_flags, VMA_DROPPABLE)) - return false; - if (vma_flags_test_any_mask(&vma_flags, VMA_SPECIAL_FLAGS)) + if (!vma_flags_is_persistent(&vma_flags)) return false; if (file_is_dax(file)) return false; diff --git a/mm/vmscan.c b/mm/vmscan.c index 12ed3388ee41..09ff20c3df5b 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3477,7 +3477,8 @@ static int should_skip_vma(unsigned long start, unsigned long end, struct mm_wal if (!vma_has_recency(vma)) return true; - if (vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) + if (vma_test(vma, VMA_LOCKED_BIT) || vma_is_kernel_owned(vma) || + vma_is_fixed_mapping(vma)) return true; if (vma == get_gate_vma(vma->vm_mm)) -- 2.55.0