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 DC4923B841B; Tue, 13 Oct 2026 11:43:51 +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=1791891833; cv=none; b=GQEzbMzM0IMP3Iwug4fXxOfzKBJr00hXPl+5ouMnjbsMHcge+gQ7M6tgjz0eQSGCV5FnDumF1aipsYbZ6mu9hfrgG+rW1710hzVZu1KnP2aWoPb/Q38Pfpmvl02xMucpT2gH5uUnrDLIpRcXPoj3GNN8WMcOk29Ks7l4z5i8GoU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791891833; c=relaxed/simple; bh=TaJk7ZnGYmGrARoPE87abyFf7X7nIEAc2yxpu5uWHoQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=nKjphG+wx8xaBJB4oZwvtMGgcVYFBGTz9BYwkzON8tT2loZiUZMct7oZlcHJEWgo+2k+9ZQnUe/3M8FRYuJ+PXuti37WlqH2ktd9wm+jLaBVUeXP2yxuqOBdVanwa1jWs7Qhkwv6y9bs3i6keVH+jOnsYpoND2+cS8l2auQShF8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JvOEi1vy; 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="JvOEi1vy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2ACB1F000FF; Tue, 13 Oct 2026 11:43:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791891831; bh=S3kwk859qFodmpxj3OxHRi9StcyZ/IRrGX/kgBYEpD4=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=JvOEi1vyoPSPHIK+3e1cFSGk5Nq5aIKf+aPMRBqWK+jdkr+GJ34ZVhlK6KFh95ok4 LFLkrLVzES/VjnqmInEE0Ue+CxRK2fSBE6/QrhXBRNAYjd1RCgj1C7FcX3LsnkXKK/ FcPKD5CYRd5utm0PX1a/JlzYfAu81YBwmUTmdu2jSQfZJQIWOLsgxo2IqY17WGdyK/ VwX9jgqE+oS/qTJ+U+MBVqNS1wFKQ3L5PC8a3V+m0KpECoP3Lv5uQdi+xwTGUWhyVU JXNNX9WvbPCWhJAa1Kpla3Kp/XCy1sGiLGPzH2fxY+k3JRj8YHefM/4npCF3FyIv1o RUlJ/KsSCGPhA== Date: Tue, 13 Oct 2026 12:43:19 +0100 From: "Lorenzo Stoakes (ARM)" To: "David Hildenbrand (Arm)" Cc: Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , 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" , 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 , 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, Ihor Solodrai , Bert Karwatzki Subject: Re: [PATCH v5 33/38] mm: eliminate VMA_SPECIAL_FLAGS usage when hugetlb explicitly tested Message-ID: References: <20261009-b4-mmap-prepare-vma-flag-sanify-v5-0-923b70125b1e@kernel.org> <20261009-b4-mmap-prepare-vma-flag-sanify-v5-33-923b70125b1e@kernel.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Oct 12, 2026 at 08:49:11PM +0200, David Hildenbrand (Arm) wrote: > On 10/9/26 20:04, Lorenzo Stoakes (ARM) wrote: > > diff --git a/mm/ksm.c b/mm/ksm.c > > index 624f37975e12..ed66a90e0031 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_mm_backed(&vma_flags)) > > return false; > > Same here, it's hard for me to tell my brain that "permanently lazyfree pages > are not backed by core-mm". Yeah :) 'mm backed' is definitely too broad for this. Will reinstate the explicit droppable check in v6. > > Acked-by: David Hildenbrand (Arm) Thanks! -- Cheers, Lorenzo