Re: [PATCH v2 0/7] MODULE_LICENSE removals, first tranche

Bjorn Helgaas
2023-02-16T17:43:40Z

[+cc PCI folks, who got the patches but not this cover letter, and
participants from the v1 posting]

On Thu, Feb 16, 2023 at 03:24:03PM +0000, Nick Alcock wrote:
> This series, based on current modules-next, is part of a treewide cleanup
> suggested by Luis Chamberlain, to remove the LICENSE_MODULE usage from
> files/objects that are not tristate. Due to recent changes to kbuild, these
> uses are now problematic. See the commit logs for more details.
>
> (The commit log prefixes and Cc lists are automatically determined using
> the script mentioned below. I've eyeballed them, and they seem reasonable:
> my apologies if they are not.)
>
> This is a small initial tranche to see if the general approach is valid:
> larger tranches can follow if desired and if these patches seem OK.
> I'll be sending a second 24-patch tranche in a few hours if this
> one meets with general approval.
>
> (In total, there are 121 patches in this series.)
>
>
> Differences from v1:
> - just remove MODULE_LICENSE, don't comment it out
> - Cc: paid maintainers as well as unpaid ones
> - improvements to the prefix determination code (notable in
> PCI: versatile in particular)
>
> The series at a whole can be found here:
> https://github.com/nickalcock/linux module-license
>
> The patch splitter (not for upstreaming!) used to prepare these
> commits can be found here:
> https://github.com/nickalcock/linux mass-split
>
> Cc: Luis Chamberlain <mcgrof@kernel.org>
> Cc: linux-modules@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
>
> Nick Alcock (7):
> kbuild, PCI: versatile: remove MODULE_LICENSE in non-modules
> kbuild, PCI: mobiveil: remove MODULE_LICENSE in non-modules
> kbuild, PCI: tegra: remove MODULE_LICENSE in non-modules
> kbuild, PCI: endpoint: remove MODULE_LICENSE in non-modules
> kbuild, PCI: hip: remove MODULE_LICENSE in non-modules
> kbuild, shpchp: remove MODULE_LICENSE in non-modules
> kbuild, PCI: dwc: remove MODULE_LICENSE in non-modules
>
> drivers/pci/controller/dwc/pcie-histb.c | 1 -
> drivers/pci/controller/mobiveil/pcie-mobiveil-plat.c | 1 -
> drivers/pci/controller/pci-tegra.c | 1 -
> drivers/pci/controller/pci-versatile.c | 1 -
> drivers/pci/controller/pcie-hisi-error.c | 1 -
> drivers/pci/endpoint/pci-ep-cfs.c | 1 -
> drivers/pci/endpoint/pci-epc-core.c | 1 -
> drivers/pci/endpoint/pci-epc-mem.c | 1 -
> drivers/pci/endpoint/pci-epf-core.c | 1 -
> drivers/pci/hotplug/shpchp_core.c | 1 -
> 10 files changed, 10 deletions(-)

I squashed these and applied to pci/kbuild for v6.3, thanks!

I added examples from the v1 posting to the commit log; let me know if
I got anything wrong:

commit 84cee45bafcb ("PCI: Remove MODULE_LICENSE so boolean drivers don't look like modules")
Author: Nick Alcock <nick.alcock@oracle.com>
Date: Thu Feb 16 15:24:04 2023 +0000

PCI: Remove MODULE_LICENSE so boolean drivers don't look like modules

Since 8b41fc4454e3 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations are
used to identify modules. As a consequence, MODULE_LICENSE in non-modules
causes modprobe to misidentify the object file as a module when it is not,
and modprobe might succeed rather than failing with a suitable error
message.

For tristate modules that can be either built-in or loaded at runtime,
modprobe succeeds in both cases:

# modprobe ext4
[exit status zero if CONFIG_EXT4_FS=y or =m]

For boolean modules like the Standard Hot Plug Controller driver (shpchp)
that cannot be loaded at runtime, modprobe should always fail like this:

# modprobe shpchp
modprobe: FATAL: Module shpchp not found in directory /lib/modules/...
[exit status non-zero regardless of CONFIG_HOTPLUG_PCI_SHPC]

but prior to this commit, shpchp_core.c contained MODULE_LICENSE, so
"modprobe shpchp" silently succeeded when it should have failed.

Remove MODULE_LICENSE in files that cannot be built as modules.

[bhelgaas: commit log, squash]
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20230216152410.4312-1-nick.alcock@oracle.com/
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>

diff --git a/drivers/pci/controller/dwc/pcie-histb.c b/drivers/pci/controller/dwc/pcie-histb.c
index 43c27812dd6d..927ae05dc920 100644
--- a/drivers/pci/controller/dwc/pcie-histb.c
+++ b/drivers/pci/controller/dwc/pcie-histb.c
@@ -450,4 +450,3 @@ static struct platform_driver histb_pcie_platform_driver = {
module_platform_driver(histb_pcie_platform_driver);

MODULE_DESCRIPTION("HiSilicon STB PCIe host controller driver");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/controller/mobiveil/pcie-mobiveil-plat.c b/drivers/pci/controller/mobiveil/pcie-mobiveil-plat.c
index f6fcd95c2bf5..c5bb87ff6d9a 100644
--- a/drivers/pci/controller/mobiveil/pcie-mobiveil-plat.c
+++ b/drivers/pci/controller/mobiveil/pcie-mobiveil-plat.c
@@ -56,6 +56,5 @@ static struct platform_driver mobiveil_pcie_driver = {

builtin_platform_driver(mobiveil_pcie_driver);

-MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Mobiveil PCIe host controller driver");
MODULE_AUTHOR("Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>");
diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c
index 929f9363e94b..5bb05564d6f8 100644
--- a/drivers/pci/controller/pci-tegra.c
+++ b/drivers/pci/controller/pci-tegra.c
@@ -2814,4 +2814,3 @@ static struct platform_driver tegra_pcie_driver = {
.remove = tegra_pcie_remove,
};
module_platform_driver(tegra_pcie_driver);
-MODULE_LICENSE("GPL");
diff --git a/drivers/pci/controller/pci-versatile.c b/drivers/pci/controller/pci-versatile.c
index 7991d334e0f1..e9a6758fe2c1 100644
--- a/drivers/pci/controller/pci-versatile.c
+++ b/drivers/pci/controller/pci-versatile.c
@@ -169,4 +169,3 @@ static struct platform_driver versatile_pci_driver = {
module_platform_driver(versatile_pci_driver);

MODULE_DESCRIPTION("Versatile PCI driver");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/controller/pcie-hisi-error.c b/drivers/pci/controller/pcie-hisi-error.c
index 7959c9c8d2bc..7d88eb696b06 100644
--- a/drivers/pci/controller/pcie-hisi-error.c
+++ b/drivers/pci/controller/pcie-hisi-error.c
@@ -324,4 +324,3 @@ static struct platform_driver hisi_pcie_error_handler_driver = {
module_platform_driver(hisi_pcie_error_handler_driver);

MODULE_DESCRIPTION("HiSilicon HIP PCIe controller error handling driver");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
index d4850bdd837f..4b8ac0ac84d5 100644
--- a/drivers/pci/endpoint/pci-ep-cfs.c
+++ b/drivers/pci/endpoint/pci-ep-cfs.c
@@ -728,4 +728,3 @@ module_exit(pci_ep_cfs_exit);

MODULE_DESCRIPTION("PCI EP CONFIGFS");
MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index 2542196e8c3d..dd750ad29485 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -861,4 +861,3 @@ module_exit(pci_epc_exit);

MODULE_DESCRIPTION("PCI EPC Library");
MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c
index a97b56a6d2db..7dcf6f480b82 100644
--- a/drivers/pci/endpoint/pci-epc-mem.c
+++ b/drivers/pci/endpoint/pci-epc-mem.c
@@ -260,4 +260,3 @@ EXPORT_SYMBOL_GPL(pci_epc_mem_free_addr);

MODULE_DESCRIPTION("PCI EPC Address Space Management");
MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
index 9ed556936f48..2036e38be093 100644
--- a/drivers/pci/endpoint/pci-epf-core.c
+++ b/drivers/pci/endpoint/pci-epf-core.c
@@ -568,4 +568,3 @@ module_exit(pci_epf_exit);

MODULE_DESCRIPTION("PCI EPF Library");
MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/hotplug/shpchp_core.c b/drivers/pci/hotplug/shpchp_core.c
index 53692b048301..56c7795ed890 100644
--- a/drivers/pci/hotplug/shpchp_core.c
+++ b/drivers/pci/hotplug/shpchp_core.c
@@ -32,7 +32,6 @@ int shpchp_poll_time;

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
-MODULE_LICENSE("GPL");

module_param(shpchp_debug, bool, 0644);
module_param(shpchp_poll_mode, bool, 0644);