[PATCH net] net/smc: Fix dependency of SMC on ISM

[Gerd Bayer]

When the SMC protocol is built into the kernel proper while ISM is
configured to be built as module, linking the kernel fails due to
unresolved dependencies out of net/smc/smc_ism.o to
ism_get_smcd_ops, ism_register_client, and ism_unregister_client
as reported via the linux-next test automation (see link).
This however is a bug introduced a while ago.

Correct the dependency list in ISM's and SMC's Kconfig to reflect the
dependencies that are actually inverted. With this you cannot build a
kernel with CONFIG_SMC=y and CONFIG_ISM=m. Either ISM needs to be 'y',
too - or a 'n'. That way, SMC can still be configured on non-s390
architectures that do not have (nor need) an ISM driver.

Fixes: 89e7d2ba61b7 ("net/ism: Add new API for client registration")

Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Closes: https://lore.kernel.org/linux-next/d53b5b50-d894-4df8-8969-fd39e63440ae@xxxxxxxxxxxxx/
Co-developed-by: Wenjia Zhang <wenjia@xxxxxxxxxxxxx>
Signed-off-by: Wenjia Zhang <wenjia@xxxxxxxxxxxxx>
Signed-off-by: Gerd Bayer <gbayer@xxxxxxxxxxxxx>
---
 drivers/s390/net/Kconfig | 2 +-
 net/smc/Kconfig          | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/s390/net/Kconfig b/drivers/s390/net/Kconfig
index 74760c1a163b..4902d45e929c 100644
--- a/drivers/s390/net/Kconfig
+++ b/drivers/s390/net/Kconfig
@@ -102,7 +102,7 @@ config CCWGROUP
 
 config ISM
 	tristate "Support for ISM vPCI Adapter"
-	depends on PCI && SMC
+	depends on PCI
 	default n
 	help
 	  Select this option if you want to use the Internal Shared Memory
diff --git a/net/smc/Kconfig b/net/smc/Kconfig
index 1ab3c5a2c5ad..746be3996768 100644
--- a/net/smc/Kconfig
+++ b/net/smc/Kconfig
@@ -2,6 +2,7 @@
 config SMC
 	tristate "SMC socket protocol family"
 	depends on INET && INFINIBAND
+	depends on m || ISM != m
 	help
 	  SMC-R provides a "sockets over RDMA" solution making use of
 	  RDMA over Converged Ethernet (RoCE) technology to upgrade
-- 
2.39.2