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Howlett" , David Hildenbrand , Vlastimil Babka , Mike Rapoport , Jann Horn , Michal Hocko , Shakeel Butt , Pedro Falcato , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: prevent VMA generation reuse from skipping readers Message-ID: References: <20261015143735.1630957-1-4ncienth@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261015143735.1630957-1-4ncienth@gmail.com> X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 6725A20008 X-Stat-Signature: e41pi7n19bct8sk3f98or39ie7u4db7a X-HE-Tag: 1792081687-147564 X-HE-Meta: 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 2ke4M0bU BfXepn93GATpznF9tkMxGbiRtX65l6P64RsWNdz7OsYnSK/kKvD2AYyug8RtOw0QgWLtqrxpJkSz5uTNbE/O7Al8aNQJIarDJz66R8HNktdul6+d2r9zYwyconcvMZVCMXzw8yDo8q8oKb4k/fU67D9jtwQDMwhzf1cQh90A55/F1OhH6NTR/gLFPcW9vQv+MDk9mtUjGAzfiDqmhJRGTrfgFXLUPV7yVhpRB256YgylZw6V6mKBnvqCxeQLlbDE/cniT Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: NAK. You're making VMAs a cache line bigger. Since this is the second time you've done this - stop sending patches to mm, we don't want your AI slop, thanks. (In future you'll likely be ignored.) On Thu, Oct 15, 2026 at 11:37:35PM +0900, Daehyeon Ko wrote: > Both values are 32-bit. After 2^31 complete mmap write-lock acquisitions, > an old VMA stamp can alias the live odd generation. vma_start_write() then > returns without waiting for an existing reader. This is really unclear, I guess, as before, a member of the core team (likely me) will assess this to see if there's anything actually valid here. -- Cheers, Lorenzo