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[173.79.60.52]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-8ffd80fe009sm47940576d6.38.2026.07.10.12.05.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Jul 2026 12:05:32 -0700 (PDT) Date: Fri, 10 Jul 2026 15:05:27 -0400 From: Gregory Price To: Lorenzo Stoakes Cc: Andrew Morton , Russell King , Dinh Nguyen , Simon Schuster , "James E . J . Bottomley" , Helge Deller , Jarkko Sakkinen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Ian Abbott , H Hartley Sweeten , Lucas Stach , David Airlie , Simona Vetter , Patrik Jakobsson , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Rob Clark , Dmitry Baryshkov , Tomi Valkeinen , Thierry Reding , Mikko Perttunen , Jonathan Hunter , Christian Koenig , Huang Rui , Ankit Agrawal , Alex Williamson , Alexander Viro , Christian Brauner , Dan Williams , Muchun Song , Oscar Salvador , David Hildenbrand , Suren Baghdasaryan , "Liam R . Howlett" , Matthew Wilcox , Marek Szyprowski , Peter Zijlstra , Arnaldo Carvalho de Melo , Namhyung Kim , Masami Hiramatsu , Oleg Nesterov , Steven Rostedt , SeongJae Park , Miaohe Lin , Hugh Dickins , Mike Rapoport , Kees Cook , Paolo Bonzini , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, linux-sgx@vger.kernel.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, linux-tegra@vger.kernel.org, kvm@vger.kernel.org, linux-fsdevel@vger.kernel.org, nvdimm@lists.linux.dev, linux-mm@kvack.org, iommu@lists.linux.dev, linux-perf-users@vger.kernel.org, linux-trace-kernel@vger.kernel.org, kasan-dev@googlegroups.com, damon@lists.linux.dev, Pedro Falcato , Rik van Riel , Harry Yoo , Jann Horn Subject: Re: [PATCH 20/30] mm/vma: introduce vma_assert_can_modify() Message-ID: References: <23c7602c58cacc23ef22618a27af9a2d54addf58.1782735110.git.ljs@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <23c7602c58cacc23ef22618a27af9a2d54addf58.1782735110.git.ljs@kernel.org> X-Stat-Signature: iegei3zbtngtn9hies4m8b93133wc9qf X-Rspamd-Queue-Id: 24297C0005 X-Rspam-User: X-Rspamd-Server: rspam07 X-HE-Tag: 1783710333-303202 X-HE-Meta: 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 dZ8siOee 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Jun 29, 2026 at 01:23:31PM +0100, Lorenzo Stoakes wrote: > vma_assert_write_locked() and vma_assert_attached() are useful for their > own purposes, however VMA code absolutely does allow the modification of > non-write locked VMAs if they are at that point detached (i.e. unreachable > from anywhere). > curiosity: I presume this happens mostly during init and/or teardown of a vma? > It's therefore useful to be able to assert that a VMA is either > detached (modification doesn't matter) or write locked (you're explicitly > locked for modification). > > Therefore introduce vma_assert_can_modify() for this purpose. > > While we're here, make vma_is_attached() available generally - if > !CONFIG_PER_VMA_LOCKS, then there's no sense in which a VMA is > detached (vma_mark_detached() is a noop), so have this default to true in > this case. > > Signed-off-by: Lorenzo Stoakes Reviewed-by: Gregory Price