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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250327092922.536-1-link@vivo.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-Rspamd-Server: rspam01 X-Stat-Signature: 6k3jrsy9e75rjpgi5z3mf77kgroqybrw X-Rspam-User: X-Rspamd-Queue-Id: C01EE18001B X-HE-Tag: 1743757279-294668 X-HE-Meta: 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 72JoxiGK RzMbtCKwJY7WpayrqObHfgB1XPtx21vzkrcG/PRNp55ESC/uV30C7d+oRH7gJyqyzR40RDwfoMlFpmDdYSjZH8sqwPxBX4wPIJBvoIMZryoPPePYGphYN+xLqtfVGmKPW0/ti6IDQWC7bItQ= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: After the btrfs compressed bio discussion I think the hugetlb changes that skip the tail pages are fundamentally unsafe in the current kernel. That is because the bio_vec representation assumes tail pages do exist, so as soon as you are doing direct I/O that generates a bvec starting beyond the present head page things will blow up. Other users of bio_vecs might do the same, but the way the block bio_vecs are generated are very suspect to that. So we'll first need to sort that out and a few other things before we can even think of enabling such a feature.