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Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , Suren Baghdasaryan , Shakeel Butt , linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org Subject: Re: [PATCH] fs/proc/task_mmu: fix missed VMAs when reading /proc/PID/maps and friends Message-ID: References: <20261025-per_vma_maps-v1-1-c4eec45b9387@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 4FECE1C0005 X-Stat-Signature: kaz9xungkw7j3urdacjnj9upepn4diak X-Rspamd-Server: rspam06 X-Spam-Status: No, score=-6.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1793021928-783727 X-HE-Meta: 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 Mu0v5Iap 4Yy6OcNJk5nS7Ov4Afsai1IGtwfRPK3HhK6CEzmPfkPOLWcDu3GvagZjb5AQCMEUOa0/iQ7OjyYKLqjMMpfFgbnocyLUg7ZDlM+Ph/W49Mz9rn3YFiHV9oZO61ImsOTTcsQ1S/f+The1zG7s27eN4fhfSZ+KRS8aRQaQ/cToqBietNA5Qp+Nw+Qw/0fmOZnp6WNC36NyfMQindAxrdaHLWpkkHa0IyE26q4c98CVTmF/Yd3pd4xsMWCVnt6Q4Fw9MKGjrRXnBs873ksJkKIuc5Ej6/i4OCtYF6Tg02DRNVD2Q6UE= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Mon, Oct 26, 2026 at 01:35:23PM +0000, Lorenzo Stoakes (ARM) wrote: > /* Returns true if mmap write unlocked. */ > static bool reset_walk_if_mmap_lock_dropped(struct vma_iterator *vmi, > struct mm_struct *mm, unsigned long from_addr, > unsigned int *last_seq) > { > if (vma_tree_maybe_changed(mm, *last_seq)) { > /* Reset walk and re-speculate. */ > vma_iter_set(vmi, from_addr); > return mmap_lock_speculate_try_begin(mm, last_seq); > } > > return true; > } Actually, nicer as: /* Returns true if mmap write unlocked. */ static bool reset_walk_if_mmap_lock_dropped(struct vma_iterator *vmi, struct mm_struct *mm, unsigned long from_addr, unsigned int *last_seq) { if (!vma_tree_maybe_changed(mm, *last_seq)) return true; /* Reset walk and re-speculate. */ vma_iter_set(vmi, from_addr); return mmap_lock_speculate_try_begin(mm, last_seq); } -- Cheers, Lorenzo