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Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Alexei Starovoitov , Daniel Borkmann , "David S . Miller" , Jakub Kicinski , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , James Bottomley , Hagen Paul Pfeifer , Pedro Falcato , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] mm/secretmem: properly account locked pages Date: Tue, 18 Aug 2026 14:20:06 +0900 Message-ID: <20260818052006.2387242-1-4ncienth@gmail.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260814-secretmem-accounting-v1-1-d2f8c677980b@kernel.org> References: <20260814-secretmem-accounting-v1-1-d2f8c677980b@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Thanks for the patch. I tested this v1 on its stated base with an x86_64 KASAN kernel. The supplied selftest passed 6/6 in three boots. Additional fork/unmap and inherited-VMA mremap tests also passed. One question: the inode stores the creator's user_struct, but the fault path uses the current task's RLIMIT_MEMLOCK. secretmem_init_inode_priv(): state->user = get_uid(current_user()); __secretmem_account_pages(): page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; With A limited to one page and B to four, A created the fd and passed it to B. B faulted four pages, after which A got SIGBUS faulting one page on a new fd: CROSS_PRINCIPAL receiver_pages=4 creator_fresh_page=0 This seems to charge A's locked_vm using B's limit. Is that intended? Thanks, Daehyeon