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Tue, 21 Apr 2026 06:50:32 -0700 (PDT) Message-ID: <842a9dff-b12c-4cec-bc8d-8c1adb3ba280@kernel.dk> Date: Tue, 21 Apr 2026 07:50:32 -0600 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] io_uring: take page references for NOMMU pbuf_ring mmaps To: Greg Kroah-Hartman , io-uring@vger.kernel.org References: <2026042115-body-attention-d15b@gregkh> Content-Language: en-US From: Jens Axboe In-Reply-To: <2026042115-body-attention-d15b@gregkh> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 4/21/26 7:46 AM, Greg Kroah-Hartman wrote: > Note, I have no way of testing this, I'm only forwarding this on because > I got the bug report and was able to generate something that "seems" AI bug report I presume? Because I can't imagine anyone ever attempted to run this. > correct, but it might be a total load of crap here, my knowledge of the > vm layer is very low so take this for where it is coming from (i.e. a > non-deterministic pattern matching system.) > > I do have another patch that just disables io_uring for !MMU systems, if > you want that instead? Or is this feature something that !MMU devices > actually care about? I mean, who really cares about !MMU in the first place, we should just kill that off with a passion. Let me take a closer look at this and bounce it past some vm people, my nommu knowledge is close to zero as it's never been relevant in my professional life time. Which is saying something... -- Jens Axboe