Re: [ANNOUNCE] kmod 30

From: Luis Chamberlain
Date: Thu Jun 30 2022 - 18:09:37 EST


On Thu, Jun 30, 2022 at 08:36:21AM -0700, Lucas De Marchi wrote:
> - modprobe learned a --wait <MSEC> option to be used together with -r
> when removing a module. This allows modprobe to keep trying the
> removal if it fails because the module is still in use. An exponential backoff
> time is used for further retries.
>
> The wait behavior provided by the kernel when not passing O_NONBLOCK
> to delete_module() was removed in v3.13 due to not be used and the
> consequences of having to support it in the kernel. However there may
> be some users, particularly on testsuites for individual susbsystems, that
> would want that. So provide a userspace implementation inside modprobe for
> such users. "rmmod" doesn't have a --wait as it remains a bare minimal over
> the API provided by the kernel. In future the --wait behavior can be added
> to libkmod for testsuites not exec'ing modprobe for module removal.

Sorry for the super late review, I was swamped. OK so the only issue
I can think of is that rmmod *used* to support the kernel wait support
with $(rmmod --wait) so wouldn't this be odd?

It is why I had gone with:

-p | --remove-patiently patiently removes the module
-t | --timeout timeout in ms to remove the module

You would know better though.

Also just curious, is it really terrible to just support waiting
forever?

Luis