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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.0 MIME-Version: 1.0 In-Reply-To: <1c0d0978-0824-b896-d100-e0b7664ba81a@kernel.dk> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 22/03/2020 20:08, Jens Axboe wrote: >>> + */ >>> + if (!work) { >>> + work = wq_first_entry(&list, >>> + struct io_wq_work, >>> + list); >> >> Wouldn't it just drop a linked request? Probably works because of the >> comment above. > > Only drops if if we always override 'work', if it's already set we use > 'work' and don't grab from the list. So that should work for links. > Oh, right, the NULL check is just above. >>> + if (work) { >>> + wq_node_del(&list, &work->list); >> >> There is a bug, apparently from one of my commits, where it do >> io_assign_current_work() but then re-enqueue and reassign new work, >> though there is a gap for cancel to happen, which would screw >> everything up. >> >> I'll send a patch, so it'd be more clear. However, this is a good >> point to look after for this as well. > > Saw it, I'll apply when you have the Fixes line. I'll respin this one > after. > -- Pavel Begunkov