On Thu, Mar 25, 2021 at 4:25 PM Christoph Hellwig [off-list ref] wrote:

On Mon, Mar 15, 2021 at 05:46:43PM +0800, Yongji Xie wrote:

quoted

On Mon, Mar 15, 2021 at 5:08 PM Christoph Hellwig [off-list ref] wrote:

quoted

On Mon, Mar 15, 2021 at 01:37:11PM +0800, Xie Yongji wrote:

quoted

Export __receive_fd() so that some modules can use
it to pass file descriptor between processes.

I really don't think any non-core code should do that, especilly not
modular mere driver code.

Do you see any issue? Now I think we're able to do that with the help
of get_unused_fd_flags() and fd_install() in modules. But we may miss
some security stuff in this way. So I try to export __receive_fd() and
use it instead.

The real problem is now what helper to use, but rather that random
drivers should not just mess with the FD table like that.

I see. I will use receive_fd() instead that only receives and installs
an fd. This is indeed needed in our cases.

Thanks,
Yongji