On 3/2/21 1:40 AM, Yang Yingliang wrote: > Hi, > > On 2020/12/1 16:53, Greg Kroah-Hartman wrote: >> From: Jens Axboe <ax...@kernel.dk> >> >> [ Upstream commit 8d4c3e76e3be11a64df95ddee52e99092d42fc19 ] >> >> If this is attempted by a kthread, then return -EOPNOTSUPP as we don't >> currently support that. Once we can get task_pid_ptr() doing the right >> thing, then this can go away again. > > https://www.spinics.net/lists/io-uring/msg05297.html > > This patch seems used for io-wq worker which is merged in > > v5.5-rc1, why we need this in linux-4.19.y ?
While that's true, it's also a sane safeguard in general. -- Jens Axboe
