On 2020/4/1 下午10:39, Michael S. Tsirkin wrote:

quoted

quoted

From 9b3a5d23b8bf6b0a11e65e688335d782f8e6aa5c Mon Sep 17 00:00:00 2001

From: Jason Wang<jasowang@redhat.com>
Date: Wed, 1 Apr 2020 22:17:27 +0800
Subject: [PATCH] vhost: let CONFIG_VHOST to be selected by drivers

The defconfig on some archs enable vhost_net or vhost_vsock by
default. So instead of adding CONFIG_VHOST=m to all of those files,
simply letting CONFIG_VHOST to be selected by all of the vhost
drivers. This fixes the build on the archs with CONFIG_VHOST_NET=m in
their defconfig.

Signed-off-by: Jason Wang<jasowang@redhat.com>
---
  drivers/vhost/Kconfig | 15 +++++++++++----
  1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 2523a1d4290a..362b832f5338 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig

@@ -11,19 +11,23 @@ config VHOST_RING
  	  This option is selected by any driver which needs to access
  	  the host side of a virtio ring.
  
-menuconfig VHOST
-	tristate "Host kernel accelerator for virtio (VHOST)"
-	depends on EVENTFD
+config VHOST
+	tristate
  	select VHOST_IOTLB
  	help
  	  This option is selected by any driver which needs to access
  	  the core of vhost.
  
-if VHOST
+menuconfig VHOST_MENU
+	bool "VHOST drivers"
+	default y
+
+if VHOST_MENU

In fact this is similar to VIRTIO, and I wonder whether VIRTIO has also
been broken by
	commit 7b95fec6d2ffa53f4a8d637b0f223644d458ea4e
	Author: Vincent Legoll[off-list ref]
	Date:   Sun Jan 7 12:33:56 2018 +0100

	    virtio: make VIRTIO a menuconfig to ease disabling it all

I see lots of defconfigs set VIRTIO_PCI but not VIRTIO_MENU ...

Probably not since VIRTIO_MENU has "default y"

E.g for powerpc, I got:

# make ARCH=powerpc defconfig
*** Default configuration is based on 'ppc64_defconfig'
#
# No change to .config
#
# grep CONFIG_VIRTIO .config
CONFIG_VIRTIO_BLK=m
CONFIG_VIRTIO_NET=m
CONFIG_VIRTIO_CONSOLE=m
CONFIG_VIRTIO=m
CONFIG_VIRTIO_MENU=y
CONFIG_VIRTIO_PCI=m
CONFIG_VIRTIO_PCI_LEGACY=y
# CONFIG_VIRTIO_VDPA is not set
CONFIG_VIRTIO_BALLOON=m
# CONFIG_VIRTIO_INPUT is not set
# CONFIG_VIRTIO_MMIO is not set
# CONFIG_VIRTIO_FS is not set

Thanks