Re: [PATCH 4.19 21/57] proc: dont allow async path resolution of /proc/self components

On 3/2/21 1:40 AM, Yang Yingliang wrote:

Hi,

On 2020/12/1 16:53, Greg Kroah-Hartman wrote:

...

From: Jens Axboe axboe@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.