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Howlett" , Jann Horn , Pedro Falcato , Mike Rapoport , Suren Baghdasaryan , Kees Cook , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Vineet Gupta , Russell King , Catalin Marinas , Will Deacon , Brian Cain , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , Dinh Nguyen , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Richard Weinberger , Anton Ivanov , Johannes Berg , Alexander Viro , Christian Brauner , Jan Kara , Xu Xin , Chengming Zhou , Michal Hocko , Paul Moore , Stephen Smalley , Ondrej Mosnacek , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-hexagon@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-um@lists.infradead.org, linux-fsdevel@vger.kernel.org, selinux@vger.kernel.org References: <51afbb2b8c3681003cc7926647e37335d793836e.1774034900.git.ljs@kernel.org> From: "Vlastimil Babka (SUSE)" Content-Language: en-US In-Reply-To: <51afbb2b8c3681003cc7926647e37335d793836e.1774034900.git.ljs@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: DDD5D1C0019 X-Stat-Signature: pinknyt5gjysknh5nhsn7n9mmc5zodue X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1774280867-867315 X-HE-Meta: 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 k0Kk9IaE w3bE79l6lsBtWtovT+tY/MJ7waQ7xpIPmqwQZ8RaK817bSkVcsomsBZNqgsHa18ugfVGwmp47wxE9kY14bp8W2X/P1bmmsVXTO9SimqEuHS5UEERXvZ4ITkcRG6OMYV1BeQ7fPiewg03Z7IlcCrt2KXMSiRV2oHdEKmOvp32+D3SXrRu+tyPebJLM5P3/2PJJasb/y/hlKh1CLXlQNYHvNCEGVWNkZQJq+w1syhzX/BBEfQvi5TlgNF2mg4FhiwSniJTSapGRcvxOdzPlWsWjv6dp0ElFghlXT7FgTMXcqmGDcAgBXJGmt/s1cb2g90lHzHOzKC7OSM/2/zPGsauHZQodgi89Kf/B8y10nntBMSrMKPLGTkiOYAsvWOWShuo+jbBTgAtoxQRcFAQnzte9C7pYgw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/20/26 8:38 PM, Lorenzo Stoakes (Oracle) wrote: > Update the vma_modify_flags() and vma_modify_flags_uffd() functions to > accept a vma_flags_t parameter rather than a vm_flags_t one, and propagate > the changes as needed to implement this change. > > Also add vma_flags_reset_once() in replacement of vm_flags_reset_once(). We > still need to be careful here because we need to avoid tearing, so maintain > the assumption that the first system word set of flags are the only ones > that require protection from tearing, and retain this functionality. > > We can copy the remainder of VMA flags above 64 bits normally. But > hopefully by the time that happens, we will have replaced the logic that > requires these WRITE_ONCE()'s with something else. > > We also replace instances of vm_flags_reset() with a simple write of VMA > flags. We are no longer perform a number of checks, most notable of all the > VMA flags asserts becase: > > 1. We might be operating on a VMA that is not yet added to the tree. > > 2. We might be operating on a VMA that is now detached. > > 3. Really in all but core code, you should be using vma_desc_xxx(). > > 4. Other VMA fields are manipulated with no such checks. > > 5. It'd be egregious to have to add variants of flag functions just to > account for cases such as the above, especially when we don't do so for > other VMA fields. Drivers are the problematic cases and why it was > especially important (and also for debug as VMA locks were introduced), > the mmap_prepare work is solving this generally. > > Additionally, we can fairly safely assume by this point the soft dirty > flags are being set correctly, so it's reasonable to drop this also. > > Finally, update the VMA tests to reflect this. > > Signed-off-by: Lorenzo Stoakes (Oracle) Acked-by: Vlastimil Babka (SUSE)