Re: git: f4e35c044c89 - main - bus: Set the current VNET in device_attach()

On 10/19/24 09:04, Mark Johnston wrote:
> The branch main has been updated by markj:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=f4e35c044c8988b7452cefbdcc417f5fd723e021
> 
> commit f4e35c044c8988b7452cefbdcc417f5fd723e021
> Author:     Mark Johnston <markj@FreeBSD.org>
> AuthorDate: 2024-10-19 13:03:56 +0000
> Commit:     Mark Johnston <markj@FreeBSD.org>
> CommitDate: 2024-10-19 13:03:56 +0000
> 
>      bus: Set the current VNET in device_attach()
>      
>      Some drivers, in particular anything which creates an ifnet during
>      attach, need to have the current VNET set, as if_attach_internal() and
>      its callees access VNET-global variables.
>      
>      device_probe_and_attach() handles this, but this is not the only way to
>      arrive in DEVICE_ATTACH.  In particular, bus drivers may invoke
>      device_attach() directly, as does devctl2's DEV_ENABLE ioctl handler.
>      So, set the current VNET in device_attach() instead.
>      
>      I believe it is always safe to use vnet0, as devctl2 ioctls are not
>      permitted within a jail.
>      
>      PR:             282168
>      Reviewed by:    zlei, kevans, bz, imp, glebius
>      MFC after:      1 week
>      Differential Revision:  https://reviews.freebsd.org/D47174

Hmm, there was some other review I thought that had a completely different change.
That change removed all the vnet stuff from new-bus and instead handled it in
if.c.  Specifically, that if_attach would set a default vnet to vnet0 if there
wasn't an active vnet at the time.  See all the discussion in
https://reviews.freebsd.org/D42678 which has a patch that I think is correct
in the comments.

-- 
John Baldwin