Re: [PATCH V2] vhost: do not enable VHOST_MENU by default

[Jason Wang]

On 2020/4/17 äå2:33, Michael S. Tsirkin wrote:
> On Fri, Apr 17, 2020 at 11:12:14AM +0800, Jason Wang wrote:
> > On 2020/4/17 äå6:55, Michael S. Tsirkin wrote:
> > > On Wed, Apr 15, 2020 at 10:43:56AM +0800, Jason Wang wrote:
> > > > We try to keep the defconfig untouched after decoupling CONFIG_VHOST
> > > > out of CONFIG_VIRTUALIZATION in commit 20c384f1ea1a
> > > > ("vhost: refine vhost and vringh kconfig") by enabling VHOST_MENU by
> > > > default. Then the defconfigs can keep enabling CONFIG_VHOST_NET
> > > > without the caring of CONFIG_VHOST.
> > > >
> > > > But this will leave a "CONFIG_VHOST_MENU=y" in all defconfigs and even
> > > > for the ones that doesn't want vhost. So it actually shifts the
> > > > burdens to the maintainers of all other to add "CONFIG_VHOST_MENU is
> > > > not set". So this patch tries to enable CONFIG_VHOST explicitly in
> > > > defconfigs that enables CONFIG_VHOST_NET and CONFIG_VHOST_VSOCK.
> > > >
> > > > Acked-by: Christian Borntraeger<borntraeger@xxxxxxxxxx>  (s390)
> > > > Acked-by: Michael Ellerman<mpe@xxxxxxxxxxxxxx>  (powerpc)
> > > > Cc: Thomas Bogendoerfer<tsbogend@xxxxxxxxxxxxxxxx>
> > > > Cc: Benjamin Herrenschmidt<benh@xxxxxxxxxxxxxxxxxxx>
> > > > Cc: Paul Mackerras<paulus@xxxxxxxxx>
> > > > Cc: Michael Ellerman<mpe@xxxxxxxxxxxxxx>
> > > > Cc: Heiko Carstens<heiko.carstens@xxxxxxxxxx>
> > > > Cc: Vasily Gorbik<gor@xxxxxxxxxxxxx>
> > > > Cc: Christian Borntraeger<borntraeger@xxxxxxxxxx>
> > > > Reported-by: Geert Uytterhoeven<geert@xxxxxxxxxxxxxx>
> > > > Signed-off-by: Jason Wang<jasowang@xxxxxxxxxx>
> > > I rebased this on top of OABI fix since that
> > > seems more orgent to fix.
> > > Pushed to my vhost branch pls take a look and
> > > if possible test.
> > > Thanks!
> >
> > I test this patch by generating the defconfigs that wants vhost_net or
> > vhost_vsock. All looks fine.
> >
> > But having CONFIG_VHOST_DPN=y may end up with the similar situation that
> > this patch want to address.
> > Maybe we can let CONFIG_VHOST depends on !ARM || AEABI then add another
> > menuconfig for VHOST_RING and do something similar?
> >
> > Thanks
> Sorry I don't understand. After this patch CONFIG_VHOST_DPN is just
> an internal variable for the OABI fix. I kept it separate
> so it's easy to revert for 5.8. Yes we could squash it into
> VHOST directly but I don't see how that changes logic at all.


Sorry for being unclear.

I meant since it was enabled by default, "CONFIG_VHOST_DPN=y" will be 
left in the defconfigs. This requires the arch maintainers to add 
"CONFIG_VHOST_VDPN is not set". (Geert complains about this)

Thanks


>