[PATCH 5.18 0536/1095] net: usb: make USB_RTL8153_ECM non user configurable

Greg Kroah-Hartman
2022-08-15T21:29:41Z

From: Maciej Żenczykowski <maze@google.com>

[ Upstream commit f56530dcdb0684406661ac9f1accf48319d07600 ]

This refixes:

commit 7da17624e7948d5d9660b910f8079d26d26ce453
nt: usb: USB_RTL8153_ECM should not default to y

In general, device drivers should not be enabled by default.

which basically broke the commit it claimed to fix, ie:

commit 657bc1d10bfc23ac06d5d687ce45826c760744f9
r8153_ecm: avoid to be prior to r8152 driver

Avoid r8153_ecm is compiled as built-in, if r8152 driver is compiled
as modules. Otherwise, the r8153_ecm would be used, even though the
device is supported by r8152 driver.

this commit amounted to:

drivers/net/usb/Kconfig:

+config USB_RTL8153_ECM
+ tristate "RTL8153 ECM support"
+ depends on USB_NET_CDCETHER && (USB_RTL8152 || USB_RTL8152=n)
+ default y
+ help
+ This option supports ECM mode for RTL8153 ethernet adapter, when
+ CONFIG_USB_RTL8152 is not set, or the RTL8153 device is not
+ supported by r8152 driver.

drivers/net/usb/Makefile:

-obj-$(CONFIG_USB_NET_CDCETHER) += cdc_ether.o r8153_ecm.o
+obj-$(CONFIG_USB_NET_CDCETHER) += cdc_ether.o
+obj-$(CONFIG_USB_RTL8153_ECM) += r8153_ecm.o

And as can be seen it pulls a piece of the cdc_ether driver out into
a separate config option to be able to make this piece modular in case
cdc_ether is builtin, while r8152 is modular.

While in general, device drivers should indeed not be enabled by default:
this isn't a device driver per say, but rather this is support code for
the CDCETHER (ECM) driver, and should thus be enabled if it is enabled.

See also email thread at:
https://www.spinics.net/lists/netdev/msg767649.html

In:
https://www.spinics.net/lists/netdev/msg768284.html

Jakub wrote:
And when we say "removed" we can just hide it from what's prompted
to the user (whatever such internal options are called)? I believe
this way we don't bring back Marek's complaint.

Side note: these incorrect defaults will result in Android 13
on 5.15 GKI kernels lacking USB_RTL8153_ECM support while having
USB_NET_CDCETHER (luckily we also have USB_RTL8150 and USB_RTL8152,
so it's probably only an issue for very new RTL815x hardware with
no native 5.15 driver).

Fixes: 7da17624e7948d5d ("nt: usb: USB_RTL8153_ECM should not default to y")
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hayes Wang <hayeswang@realtek.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Link: https://lore.kernel.org/r/20220730230113.4138858-1-zenczykowski@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/usb/Kconfig | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/usb/Kconfig b/drivers/net/usb/Kconfig
index e62fc4f2aee0..76659c1c525a 100644
--- a/drivers/net/usb/Kconfig
+++ b/drivers/net/usb/Kconfig
@@ -637,8 +637,9 @@ config USB_NET_AQC111
* Aquantia AQtion USB to 5GbE

config USB_RTL8153_ECM
- tristate "RTL8153 ECM support"
+ tristate
depends on USB_NET_CDCETHER && (USB_RTL8152 || USB_RTL8152=n)
+ default y
help
This option supports ECM mode for RTL8153 ethernet adapter, when
CONFIG_USB_RTL8152 is not set, or the RTL8153 device is not
--
2.35.1