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

[Jason Wang <jasowang@redhat.com>]

On 2020/4/17 下午2:33, Michael S. Tsirkin wrote:
> On Fri, Apr 17, 2020 at 11:12:14AM +0800, Jason Wang wrote:
>> On 2020/4/17 上午6:55, 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@de.ibm.com>  (s390)
>>>> Acked-by: Michael Ellerman<mpe@ellerman.id.au>  (powerpc)
>>>> Cc: Thomas Bogendoerfer<tsbogend@alpha.franken.de>
>>>> Cc: Benjamin Herrenschmidt<benh@kernel.crashing.org>
>>>> Cc: Paul Mackerras<paulus@samba.org>
>>>> Cc: Michael Ellerman<mpe@ellerman.id.au>
>>>> Cc: Heiko Carstens<heiko.carstens@de.ibm.com>
>>>> Cc: Vasily Gorbik<gor@linux.ibm.com>
>>>> Cc: Christian Borntraeger<borntraeger@de.ibm.com>
>>>> Reported-by: Geert Uytterhoeven<geert@linux-m68k.org>
>>>> Signed-off-by: Jason Wang<jasowang@redhat.com>
>>> 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


>