Re: [PATCH v2 2/3] iommufd/device: Make hwpt_list list_add/del symmetric

From: Nicolin Chen
Date: Sun Jan 29 2023 - 04:31:44 EST


On Sun, Jan 29, 2023 at 09:24:38AM +0000, Tian, Kevin wrote:
> External email: Use caution opening links or attachments
>
>
> > From: Nicolin Chen <nicolinc@xxxxxxxxxx>
> > Sent: Sunday, January 29, 2023 5:18 AM
> >
> > Since the list_del() of hwpt_item is done in iommufd_device_detach(), move
> > its list_add_tail() to a similar place in iommufd_device_do_attach().
>
> It's clearer to say that because list_del() is together with
> iopt_table_remove_domain() then it makes sense to have list_add_tail()
> together with iopt_table_add_domain().

OK. Will change that.

> >
> > Also move and place the mutex outside the
> > iommufd_device_auto_get_domain()
> > and iommufd_device_do_attach() calls, to serialize attach/detach routines.
> > This adds an additional locking protection so that the following patch can
> > safely remove devices_lock.
> >
> > Co-developed-by: Yi Liu <yi.l.liu@xxxxxxxxx>
> > Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
> > Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
>
> Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>

And add this too. Thanks!

Nicolin