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Mon, 01 Sep 2025 07:37:44 -0700 (PDT) From: Jens Axboe To: hch@lst.de, houtao1@huawei.com, Yu Kuai Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com In-Reply-To: <20250811065628.1829339-1-yukuai1@huaweicloud.com> References: <20250811065628.1829339-1-yukuai1@huaweicloud.com> Subject: Re: [PATCH v3] brd: use page reference to protect page lifetime Message-Id: <175673746364.13707.6940913855936222519.b4-ty@kernel.dk> Date: Mon, 01 Sep 2025 08:37:43 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Mailer: b4 0.14.3-dev-2ce6c On Mon, 11 Aug 2025 14:56:28 +0800, Yu Kuai wrote: > As discussed [1], hold rcu for copying data from/to page is too heavy, > it's better to protect page with rcu around for page lookup and then > grab a reference to prevent page to be freed by discard. > > [1] https://lore.kernel.org/all/eb41cab3-5946-4fe3-a1be-843dd6fca159@kernel.dk/ > > > [...] Applied, thanks! [1/1] brd: use page reference to protect page lifetime commit: 2a0614522885b136e9e650791c794dd49abb5b31 Best regards, -- Jens Axboe