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 C136E53D9FD; Thu, 17 Sep 2026 16:40:48 +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=1789663250; cv=none; b=KjnObt+WeQUkml2nTwzV310gmrVXXqXm4mZpl+wqUfdlq5fUDn+P+I/tIQF34J1HyE/9gvbD5gJdJ5OvGADKLCOLdlDu632G4xeyGB6Y0eDlWxxFAoqq8fpsiMsaaBgngzpWmerf51FGW1No1JP/bIftZULkx3gE+6gZH7byF9s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789663250; c=relaxed/simple; bh=DL5e220u7y3LwD4Eiaa74zWyGi+IuXsLh7IOYBtbckQ=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=okO5qdfypyg/+iKO1jsikB8lSbI/EsqPumRi5oiSACErJo85x58gnOz06+3SaIvvC93uadF6YzZ3ck7imf7VHSj97PeI96o/0U7v4NNk/jPelpaEV8XC0IvAvxshK5TnszanMXhIt8o5W1AHVm2dRSPZBQyDzUIlWNLHF31dkPA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Gspn9qQ7; 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="Gspn9qQ7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 213F61F000FF; Thu, 17 Sep 2026 16:40:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789663248; bh=1QRQ9WYzmW2nABpmD05iYHWtoRPkYuNGcAfZon3VB64=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=Gspn9qQ7Co3hTNTbvqHEG4UcsqEuAaXs4WpY+IWArwLJpD+5im1F/7UjZBYzBxEFP r6kNzzWv/ygP9N4CBTIF6SK4Me1N+TZ7kg6quLRtughmHxBkfXwla981QkTLotSK4V PNjnrxnE7nvQlWvnL9nNWOrPkCRYAY+FZPJilWJSHjfUPF9+dMlR6D9G7cKVnY5zew CY9et4FnP9P/JyfZel2Guas6YNCbujBjaIbwC7sV5R2ANs6rbBZryLjyMGMzIfInyM 67LHWbWvbSV5TTZ0+n/kZZXO1u8Gous31lF+kG/dEXbhUdNWe84ivAYvKYlYgwsB+w kA8OssQfVfUsg== From: "Lorenzo Stoakes (ARM)" Date: Thu, 17 Sep 2026 17:22:44 +0100 Subject: [PATCH v3 35/40] mm: eliminate VMA_SPECIAL_FLAGS check in lru_gen_look_around() 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-v3-35-4583d8a23bca@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=1176; i=ljs@kernel.org; h=from:subject:message-id; bh=DL5e220u7y3LwD4Eiaa74zWyGi+IuXsLh7IOYBtbckQ=; b=owGbwMvMwCV2fu7ZrsZH9SKMp9WSGLLWCB9hLL35ff77dPnnyjWxyxtOXnb5+35nmharbKxQy 6vMp54JHaUsDGJcDLJiiizPv4jvDxIJm9d5wd8NZg4rE8gQBi5OAZiIqy/Db9aa5weOsMxRtPrs HCqQHviv6mfnxF/xdR/y2ZT0lC4lMTL8M7Jx8PFZKXNRYHPiW8EVFv+upxuICcwLWyu1R4MnxHw zCwA= X-Developer-Key: i=ljs@kernel.org; a=openpgp; fpr=E7F417BF5214569E89D04F46CF9DCD8A81E27F14 A kernel-owned or fixed mapping is one which sets VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT or VMA_DONTEXPAND_BIT, which is precisely what VMA_SPECIAL_FLAGS tests for other than VMA_IO_BIT, which is safe to drop as only kernel-owned mappings may set it. Using these predicates rather than VMA_SPECIAL_FLAGS makes the check self-documenting and helps eliminate the confusion around 'special' flags. No functional change intended. Signed-off-by: Lorenzo Stoakes (ARM) --- mm/vmscan.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 09ff20c3df5b..001f8b760266 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4418,8 +4418,8 @@ bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw, unsigned int nr) if (spin_is_contended(pvmw->ptl)) return true; - /* exclude special VMAs containing anon pages from COW */ - if (vma->vm_flags & VM_SPECIAL) + /* exclude kernel-owned and fixed VMAs containing anon pages from COW */ + if (vma_is_kernel_owned(vma) || vma_is_fixed_mapping(vma)) return true; /* avoid taking the LRU lock under the PTL when possible */ -- 2.55.0