[PATCH v2 0/5] drivers/tty: make more bool drivers explicitly non-modular

[PATCH v2 0/5] drivers/tty: make more bool drivers explicitly non-modular

[Paul Gortmaker]

[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/1437530538-5078-1-git-send-email-paul.gortmaker at windriver.com
--

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Joachim Eastwood <manabian@gmail.com>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linuxppc-dev at lists.ozlabs.org
Cc: linux-serial at vger.kernel.org

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

[PATCH 5/5] drivers/tty: make serial 8250_lpc18xx.c Kconfig a tristate

[Paul Gortmaker]

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 <manabian@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Joachim Eastwood <manabian@gmail.com>
Cc: linux-serial at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
 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

[PATCH 5/5] drivers/tty: make serial 8250_lpc18xx.c Kconfig a tristate

[Joachim Eastwood]

On 19 August 2015 at 23:48, Paul Gortmaker <paul.gortmaker@windriver.com> 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 <manabian@gmail.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.com>
> Cc: Joachim Eastwood <manabian@gmail.com>
> Cc: linux-serial at vger.kernel.org
> Cc: linux-arm-kernel at lists.infradead.org
> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

Acked-by: Joachim Eastwood <manabian@gmail.com>

Build tested as a module on lpc18xx.

Thanks for fixing it Paul.


regards,
Joachim Eastwood

[PATCH v2 0/5] drivers/tty: make more bool drivers explicitly non-modular

[Paul Gortmaker]

[[PATCH v2 0/5] drivers/tty: make more bool drivers explicitly non-modular] On 19/08/2015 (Wed 17:48) Paul Gortmaker wrote:

> [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.

Hi Greg -- wondering if this is still in your to-do queue.  I see the
patches to drivers/char that I sent about the same time made it onto
your char-testing branch but not these onto tty-testing.

The reason I ask is that I've about a 1/2 dozen more similar patches
that showed up once I started auditing non-x86 code.  I don't want to
re-spam you with these along with the new ones, if these are still in
your backlog for processing.

Thanks,
Paul.
--

> 
> 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/1437530538-5078-1-git-send-email-paul.gortmaker at windriver.com
> --
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.com>
> Cc: Joachim Eastwood <manabian@gmail.com>
> Cc: linux-arm-kernel at lists.infradead.org
> Cc: linuxppc-dev at lists.ozlabs.org
> Cc: linux-serial at vger.kernel.org
> 
> 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
> 

[PATCH v2 0/5] drivers/tty: make more bool drivers explicitly non-modular

[Greg Kroah-Hartman]

On Sat, Sep 26, 2015 at 06:53:47PM -0400, Paul Gortmaker wrote:
> [[PATCH v2 0/5] drivers/tty: make more bool drivers explicitly non-modular] On 19/08/2015 (Wed 17:48) Paul Gortmaker wrote:
> 
> > [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.
> 
> Hi Greg -- wondering if this is still in your to-do queue.  I see the
> patches to drivers/char that I sent about the same time made it onto
> your char-testing branch but not these onto tty-testing.

Yes, they are in my queue, haven't caught up with tty patches yet :(

> The reason I ask is that I've about a 1/2 dozen more similar patches
> that showed up once I started auditing non-x86 code.  I don't want to
> re-spam you with these along with the new ones, if these are still in
> your backlog for processing.

I can handle resends and other patches just fine, send away!

thanks,

greg k-h