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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 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, Ihor Solodrai , Bert Karwatzki 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> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/9/26 20:04, Lorenzo Stoakes (ARM) wrote: > It is now an invariant that VMA_IO_BIT is not set by mm-managed 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 fixed or non-mm-managed mapping. > > Update a number of callsites which already explicitly handle hugetlb > mappings. > > vma_supports_mlock() and ksm_compatible() also explicitly bail on droppable > mappings - excluding non-mm-managed, fixed or droppable mappings is exactly > what vma_is_mm_backed() tests for, so in these cases use this predicate. > > should_skip_vma() tests for locked, fixed or non-mm-managed memory (having > already excluded hugetlb mappings) so simply test for those there. > > No functional change intended. > > Reviewed-by: Zi Yan > 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 b5f7be8f65d8..e57c35e5f90b 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -1112,9 +1112,7 @@ 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_mm_backed(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..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". Acked-by: David Hildenbrand (Arm) -- Cheers, David