[v2: drop dead module code removal from 8250_lpc18xx.c ; instead convert it
from bool to tristate ; also add ack to hvc_console commit.]
This second set of patches to drivers/tty steps outside of the serial
dir, and an improved auditing finds two more serial drivers pretending
to be modular that really are not.
The reasoning for doing this is the same as the first set[1] of patches
and is largely copied below:
In the previous merge window, we made changes to allow better
delineation between modular and non-modular code in commit
0fd972a7d91d6e15393c449492a04d94c0b89351 ("module: relocate module_init
from init.h to module.h"). This allows us to now ensure module code
looks modular and non-modular code does not accidentally look modular
without suffering build breakage.
Here we target code that is, by nature of their Kconfig settings, only
available to be built-in, but implicitly presenting itself as being
possibly modular by way of using modular headers, macros, and functions.
The goal here is to remove that illusion of modularity from these
drivers, but in a way that leaves the actual runtime unchanged.
In doing so, we remove code that has never been tested and adds
no value to the tree. And we begin the process of expecting a
level of consistency between the Kconfig of a driver and the code
that the driver uses.
Build tested for allyesconfig on x86_64, and ARM for lpc81xx, and powerpc
for hvc_console and mpsc, layered onto tty/tty-next as a baseline.
Paul.
[1] https://lkml.kernel.org/r/[email protected]
--
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Joachim Eastwood <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Paul Gortmaker (5):
drivers/tty: make pty.c slightly more explicitly non-modular
drivers/tty: make sysrq.c slightly more explicitly non-modular
drivers/tty: make hvc_console.c explicitly non-modular
drivers/tty: make serial/mpsc.c driver explicitly non-modular
drivers/tty: make serial 8250_lpc18xx.c Kconfig a tristate
drivers/tty/hvc/hvc_console.c | 18 +-----------------
drivers/tty/pty.c | 7 +++++--
drivers/tty/serial/8250/Kconfig | 2 +-
drivers/tty/serial/mpsc.c | 36 +++---------------------------------
drivers/tty/sysrq.c | 6 +++++-
5 files changed, 15 insertions(+), 54 deletions(-)
--
2.5.0
The Kconfig currently controlling compilation of this code is:
drivers/tty/Kconfig:config LEGACY_PTYS
drivers/tty/Kconfig: bool "Legacy (BSD) PTY support"
...and:
drivers/tty/Kconfig:config UNIX98_PTYS
drivers/tty/Kconfig: bool "Unix98 PTY support" if EXPERT
combined with this:
obj-$(CONFIG_LEGACY_PTYS) += pty.o
obj-$(CONFIG_UNIX98_PTYS) += pty.o
...meaning that it currently is not being built as a module by anyone.
Lets remove the traces of modularity we can so that when reading the
driver there is less doubt it is builtin-only.
Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.
We don't delete the module.h include since other parts of the file are
using content from there.
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>
---
drivers/tty/pty.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 4d5937c185c1..a45660f62db5 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -7,7 +7,6 @@
*/
#include <linux/module.h>
-
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
@@ -501,6 +500,10 @@ static int pty_bsd_ioctl(struct tty_struct *tty,
}
static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
+/*
+ * not really modular, but the easiest way to keep compat with existing
+ * bootargs behaviour is to continue using module_param here.
+ */
module_param(legacy_count, int, 0);
/*
@@ -877,4 +880,4 @@ static int __init pty_init(void)
unix98_pty_init();
return 0;
}
-module_init(pty_init);
+device_initcall(pty_init);
--
2.5.0
The Kconfig currently controlling compilation of this code is:
config.debug:config MAGIC_SYSRQ
bool "Magic SysRq key"
...meaning that it currently is not being built as a module by anyone.
Lets remove the traces of modularity we can so that when reading the
driver there is less doubt it is builtin-only.
Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.
We don't delete the module.h include since other parts of the file are
using content from there.
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>
---
drivers/tty/sysrq.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index b5b427888b24..dd2c435e223e 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -996,6 +996,10 @@ static const struct kernel_param_ops param_ops_sysrq_reset_seq = {
#define param_check_sysrq_reset_seq(name, p) \
__param_check(name, p, unsigned short)
+/*
+ * not really modular, but the easiest way to keep compat with existing
+ * bootargs behaviour is to continue using module_param here.
+ */
module_param_array_named(reset_seq, sysrq_reset_seq, sysrq_reset_seq,
&sysrq_reset_seq_len, 0644);
@@ -1112,4 +1116,4 @@ static int __init sysrq_init(void)
return 0;
}
-module_init(sysrq_init);
+device_initcall(sysrq_init);
--
2.5.0
The Kconfig currently controlling compilation of this code is:
drivers/tty/hvc/Kconfig:config HVC_DRIVER
drivers/tty/hvc/Kconfig: bool
...meaning that it currently is not being built as a module by anyone.
Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only, even
though someone bothered to comment that the code was not used.
Unlike other changes, this driver binds in w/o using module_init,
so we dont have init ordering concerns with this commit.
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Acked-by: Michael Ellerman <[email protected]>
Cc: [email protected]
Signed-off-by: Paul Gortmaker <[email protected]>
---
drivers/tty/hvc/hvc_console.c | 18 +-----------------
1 file changed, 1 insertion(+), 17 deletions(-)
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index 4e9c4cc9e1b5..9c30f67c802a 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -29,7 +29,7 @@
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/list.h>
-#include <linux/module.h>
+#include <linux/init.h>
#include <linux/major.h>
#include <linux/atomic.h>
#include <linux/sysrq.h>
@@ -1005,19 +1005,3 @@ put_tty:
out:
return err;
}
-
-/* This isn't particularly necessary due to this being a console driver
- * but it is nice to be thorough.
- */
-static void __exit hvc_exit(void)
-{
- if (hvc_driver) {
- kthread_stop(hvc_task);
-
- tty_unregister_driver(hvc_driver);
- /* return tty_struct instances allocated in hvc_init(). */
- put_tty_driver(hvc_driver);
- unregister_console(&hvc_console);
- }
-}
-module_exit(hvc_exit);
--
2.5.0
The Kconfig for this driver is currently:
config SERIAL_MPSC
bool "Marvell MPSC serial port support"
...meaning that it currently is not being built as a module by anyone.
Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.
Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.
We leave some tags like MODULE_AUTHOR for documentation purposes.
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: [email protected]
Signed-off-by: Paul Gortmaker <[email protected]>
---
drivers/tty/serial/mpsc.c | 36 +++---------------------------------
1 file changed, 3 insertions(+), 33 deletions(-)
diff --git a/drivers/tty/serial/mpsc.c b/drivers/tty/serial/mpsc.c
index 82bb6d1fe23b..edb32e3f1e84 100644
--- a/drivers/tty/serial/mpsc.c
+++ b/drivers/tty/serial/mpsc.c
@@ -55,8 +55,6 @@
#define SUPPORT_SYSRQ
#endif
-#include <linux/module.h>
-#include <linux/moduleparam.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/ioport.h>
@@ -2108,24 +2106,8 @@ static int mpsc_drv_probe(struct platform_device *dev)
return rc;
}
-static int mpsc_drv_remove(struct platform_device *dev)
-{
- pr_debug("mpsc_drv_exit: Removing MPSC %d\n", dev->id);
-
- if (dev->id < MPSC_NUM_CTLRS) {
- uart_remove_one_port(&mpsc_reg, &mpsc_ports[dev->id].port);
- mpsc_release_port((struct uart_port *)
- &mpsc_ports[dev->id].port);
- mpsc_drv_unmap_regs(&mpsc_ports[dev->id]);
- return 0;
- } else {
- return -ENODEV;
- }
-}
-
static struct platform_driver mpsc_driver = {
.probe = mpsc_drv_probe,
- .remove = mpsc_drv_remove,
.driver = {
.name = MPSC_CTLR_NAME,
},
@@ -2156,22 +2138,10 @@ static int __init mpsc_drv_init(void)
return rc;
}
+device_initcall(mpsc_drv_init);
-static void __exit mpsc_drv_exit(void)
-{
- platform_driver_unregister(&mpsc_driver);
- platform_driver_unregister(&mpsc_shared_driver);
- uart_unregister_driver(&mpsc_reg);
- memset(mpsc_ports, 0, sizeof(mpsc_ports));
- memset(&mpsc_shared_regs, 0, sizeof(mpsc_shared_regs));
-}
-
-module_init(mpsc_drv_init);
-module_exit(mpsc_drv_exit);
-
+/*
MODULE_AUTHOR("Mark A. Greer <[email protected]>");
MODULE_DESCRIPTION("Generic Marvell MPSC serial/UART driver");
-MODULE_VERSION(MPSC_VERSION);
MODULE_LICENSE("GPL");
-MODULE_ALIAS_CHARDEV_MAJOR(MPSC_MAJOR);
-MODULE_ALIAS("platform:" MPSC_CTLR_NAME);
+*/
--
2.5.0
The Kconfig currently controlling compilation of this code is:
8250/Kconfig:config SERIAL_8250_LPC18XX
8250/Kconfig: bool "NXP LPC18xx/43xx serial port support"
...meaning that it currently is not being built as a module by anyone.
When targetting orphaned modular code in non-modular drivers, this
came up. Joachim indicated that the driver was actually meant to
be tristate but ended up bool by accident. So here we make it
tristate instead of removing the modular code that was essentially
orphaned.
Suggested-by: Joachim Eastwood <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Joachim Eastwood <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Paul Gortmaker <[email protected]>
---
drivers/tty/serial/8250/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index e1de1181b322..f5c4b01f6f1d 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -337,7 +337,7 @@ config SERIAL_8250_FINTEK
through the PNP driver. If unsure, say N.
config SERIAL_8250_LPC18XX
- bool "NXP LPC18xx/43xx serial port support"
+ tristate "NXP LPC18xx/43xx serial port support"
depends on SERIAL_8250 && OF && (ARCH_LPC18XX || COMPILE_TEST)
default ARCH_LPC18XX
help
--
2.5.0
On 19 August 2015 at 23:48, Paul Gortmaker <[email protected]> wrote:
> The Kconfig currently controlling compilation of this code is:
>
> 8250/Kconfig:config SERIAL_8250_LPC18XX
> 8250/Kconfig: bool "NXP LPC18xx/43xx serial port support"
>
> ...meaning that it currently is not being built as a module by anyone.
>
> When targetting orphaned modular code in non-modular drivers, this
> came up. Joachim indicated that the driver was actually meant to
> be tristate but ended up bool by accident. So here we make it
> tristate instead of removing the modular code that was essentially
> orphaned.
>
> Suggested-by: Joachim Eastwood <[email protected]>
> Cc: Greg Kroah-Hartman <[email protected]>
> Cc: Jiri Slaby <[email protected]>
> Cc: Joachim Eastwood <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Paul Gortmaker <[email protected]>
Acked-by: Joachim Eastwood <[email protected]>
Build tested as a module on lpc18xx.
Thanks for fixing it Paul.
regards,
Joachim Eastwood