[PATCH v3 00/11] Symbol Namespaces

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* [PATCH v3 00/11] Symbol Namespaces
       [not found] ` <20190813121733.52480-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
@ 2019-08-21 11:49   ` Matthias Maennich
       [not found]     ` <20190821114955.12788-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
  0 siblings, 1 reply; 11+ messages in thread
From: Matthias Maennich @ 2019-08-21 11:49 UTC (permalink / raw)
  To: linux-kernel-u79uwXL29TY76Z2rM5mHXA
  Cc: kstewart-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, oneukum-IBi9RG/b67k,
	linux-stm32-XDFAJ8BFU24N7RejjzZ/Li2xQDfSxrLKVpNB7YpNyf8,
	linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	usb-storage-ijkIwGHArpdIPJnuZ7Njw4oP9KaGy4wf, Toru Komatsu,
	Mauro Carvalho Chehab, David Howells,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A, Will Deacon,
	patches-yzvPICuk2AA4QjBA90+/kJqQE7yCjDx5, Michael Ellerman,
	hpa-YMNOUZJC4hwAvxtiuMwx3w, joel-QYYGw3jwrUn5owFQY34kdNi2O/JbrIOy,
	bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w,
	sam-uyr5N9Q2VtJg9hUCZPvPmw, cocci-/FJkirnvOdkvYVN+rsErww,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Benjamin Fair,
	linux-scsi-u79uwXL29TY76Z2rM5mHXA, Fabio Estevam,
	openbmc-uLR06cmDAlY/bJ5BZ2RsiQ, x86-DgEjT+Ai2ygdnm+yROfE0A,
	lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w, Nancy Yuen,
	mingo-H+wXaHxf7aLQT0dZR+AlfA, geert-Td1EMuHUCqxL1ZNQvxDV9g,
	NXP Linux Team, Johannes

As of Linux 5.3-rc5, there are 31205 [1] exported symbols in the kernel.
That is a growth of roughly 1000 symbols since 4.17 (30206 [2]).  There
seems to be some consensus amongst kernel devs that the export surface
is too large, and hard to reason about.

Generally, these symbols fall in one of these categories:
1) Symbols actually meant for drivers
2) Symbols that are only exported because functionality is split over
   multiple modules, yet they really shouldn't be used by modules outside
   of their own subsystem
3) Symbols really only meant for in-tree use

When module developers try to upstream their code, it regularly turns
out that they are using exported symbols that they really shouldn't be
using. This problem is even bigger for drivers that are currently
out-of-tree, which may be using many symbols that they shouldn't be
using, and that break when those symbols are removed or modified.

This patch allows subsystem maintainers to partition their exported
symbols into separate namespaces, and module authors to import such
namespaces only when needed.

This allows subsystem maintainers to more easily limit availability of
these namespaced symbols to other parts of the kernel. It can also be
used to partition the set of exported symbols for documentation
purposes; for example, a set of symbols that is really only used for
debugging could be in a "SUBSYSTEM_DEBUG" namespace.

I continued the work mainly done by Martijn Coenen.

Changes in v2:
- Rather than adding and evaluating separate sections __knsimport_NS,
  use modinfo tags to declare the namespaces a module introduces.
  Adjust modpost and the module loader accordingly.
- Also add support for reading multiple modinfo values for the same tag
  to allow list-like access to modinfo tags.
- The macros in export.h have been cleaned up to avoid redundancy in the
  macro parameters (ns, nspost, nspost2).
- The introduction of relative references in the ksymtab entries caused
  a rework of the macros to accommodate that configuration as well.
- Alignment of kernel_symbol in the ksymtab needed to be fixed to allow
  growing the kernel_symbol struct.
- Modpost does now also append the namespace suffix to the symbol
  entries in Module.symvers.
- The configuration option MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS allows
  relaxing the enforcement of properly declared namespace imports at
  module loading time.
- Symbols can be collectively exported into a namespace by defining
  DEFAULT_SYMBOL_NAMESPACE in the corresponding Makefile.
- The requirement for a very recent coccinelle spatch has been lifted by
  simplifying the script.
- nsdeps does now ensures MODULE_IMPORT_NS statements are sorted when
  patching the module source files.
- Some minor bugs have been addressed in nsdeps to allow it to work with
  modules that have more than one source file.
- The RFC for the usb-storage symbols has been simplified by using
  DEFAULT_SYMBOL_NAMESPACE=USB_STORAGE rather than explicitly exporting
  each and every symbol into that new namespace.

Changes in v3:
- Reword the documentation for the
  MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS option for clarification.
- Fix printed required version of spatch in coccinelle script.
- Adopt kbuild changes for modpost: .mod files are no longer generated
  in .tmp_versions. Similarely, generate the .ns_deps files in the tree
  along with the .mod files. Also, nsdeps now uses modules.order as
  source for the list modules to consider.
- Add an RFC patch to introduce the namespace WATCHDOG_CORE for symbols
  exported in watchdog_core.c.

This patch series was developed against Linus' master (15d90b242290).

[1] git grep "^EXPORT_SYMBOL\w*(" v5.3-rc5 | wc -l
[2] git grep "^EXPORT_SYMBOL\w*(" v4.17    | wc -l


Matthias Maennich (11):
  module: support reading multiple values per modinfo tag
  export: explicitly align struct kernel_symbol
  module: add support for symbol namespaces.
  modpost: add support for symbol namespaces
  module: add config option MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
  export: allow definition default namespaces in Makefiles or sources
  modpost: add support for generating namespace dependencies
  scripts: Coccinelle script for namespace dependencies.
  usb-storage: remove single-use define for debugging
  RFC: usb-storage: export symbols in USB_STORAGE namespace
  RFC: watchdog: export core symbols in WATCHDOG_CORE namespace

 .gitignore                                  |   1 +
 MAINTAINERS                                 |   5 +
 Makefile                                    |  14 +-
 arch/m68k/include/asm/export.h              |   1 -
 drivers/hwmon/ftsteutates.c                 |   1 +
 drivers/hwmon/sch56xx-common.c              |   1 +
 drivers/rtc/rtc-abx80x.c                    |   1 +
 drivers/usb/storage/Makefile                |   2 +
 drivers/usb/storage/alauda.c                |   1 +
 drivers/usb/storage/cypress_atacb.c         |   1 +
 drivers/usb/storage/datafab.c               |   1 +
 drivers/usb/storage/debug.h                 |   2 -
 drivers/usb/storage/ene_ub6250.c            |   1 +
 drivers/usb/storage/freecom.c               |   1 +
 drivers/usb/storage/isd200.c                |   1 +
 drivers/usb/storage/jumpshot.c              |   1 +
 drivers/usb/storage/karma.c                 |   1 +
 drivers/usb/storage/onetouch.c              |   1 +
 drivers/usb/storage/realtek_cr.c            |   1 +
 drivers/usb/storage/scsiglue.c              |   2 +-
 drivers/usb/storage/sddr09.c                |   1 +
 drivers/usb/storage/sddr55.c                |   1 +
 drivers/usb/storage/shuttle_usbat.c         |   1 +
 drivers/usb/storage/uas.c                   |   1 +
 drivers/watchdog/armada_37xx_wdt.c          |   1 +
 drivers/watchdog/asm9260_wdt.c              |   1 +
 drivers/watchdog/aspeed_wdt.c               |   1 +
 drivers/watchdog/at91sam9_wdt.c             |   1 +
 drivers/watchdog/atlas7_wdt.c               |   1 +
 drivers/watchdog/bcm2835_wdt.c              |   1 +
 drivers/watchdog/bcm47xx_wdt.c              |   1 +
 drivers/watchdog/bcm7038_wdt.c              |   1 +
 drivers/watchdog/bcm_kona_wdt.c             |   1 +
 drivers/watchdog/bd70528_wdt.c              |   1 +
 drivers/watchdog/cadence_wdt.c              |   1 +
 drivers/watchdog/da9052_wdt.c               |   1 +
 drivers/watchdog/da9055_wdt.c               |   1 +
 drivers/watchdog/da9062_wdt.c               |   1 +
 drivers/watchdog/da9063_wdt.c               |   1 +
 drivers/watchdog/davinci_wdt.c              |   1 +
 drivers/watchdog/digicolor_wdt.c            |   1 +
 drivers/watchdog/dw_wdt.c                   |   1 +
 drivers/watchdog/ebc-c384_wdt.c             |   1 +
 drivers/watchdog/ep93xx_wdt.c               |   1 +
 drivers/watchdog/ftwdt010_wdt.c             |   1 +
 drivers/watchdog/gpio_wdt.c                 |   1 +
 drivers/watchdog/hpwdt.c                    |   1 +
 drivers/watchdog/i6300esb.c                 |   1 +
 drivers/watchdog/iTCO_wdt.c                 |   1 +
 drivers/watchdog/ie6xx_wdt.c                |   1 +
 drivers/watchdog/imgpdc_wdt.c               |   1 +
 drivers/watchdog/imx2_wdt.c                 |   1 +
 drivers/watchdog/intel-mid_wdt.c            |   1 +
 drivers/watchdog/it87_wdt.c                 |   1 +
 drivers/watchdog/kempld_wdt.c               |   1 +
 drivers/watchdog/lpc18xx_wdt.c              |   1 +
 drivers/watchdog/max63xx_wdt.c              |   1 +
 drivers/watchdog/max77620_wdt.c             |   1 +
 drivers/watchdog/mei_wdt.c                  |   1 +
 drivers/watchdog/mena21_wdt.c               |   1 +
 drivers/watchdog/menf21bmc_wdt.c            |   1 +
 drivers/watchdog/menz69_wdt.c               |   1 +
 drivers/watchdog/meson_gxbb_wdt.c           |   1 +
 drivers/watchdog/meson_wdt.c                |   1 +
 drivers/watchdog/mlx_wdt.c                  |   1 +
 drivers/watchdog/moxart_wdt.c               |   1 +
 drivers/watchdog/mtk_wdt.c                  |   1 +
 drivers/watchdog/ni903x_wdt.c               |   1 +
 drivers/watchdog/nic7018_wdt.c              |   1 +
 drivers/watchdog/npcm_wdt.c                 |   1 +
 drivers/watchdog/of_xilinx_wdt.c            |   1 +
 drivers/watchdog/omap_wdt.c                 |   1 +
 drivers/watchdog/pm8916_wdt.c               |   1 +
 drivers/watchdog/qcom-wdt.c                 |   1 +
 drivers/watchdog/rave-sp-wdt.c              |   1 +
 drivers/watchdog/renesas_wdt.c              |   1 +
 drivers/watchdog/retu_wdt.c                 |   1 +
 drivers/watchdog/rn5t618_wdt.c              |   1 +
 drivers/watchdog/rza_wdt.c                  |   1 +
 drivers/watchdog/s3c2410_wdt.c              |   1 +
 drivers/watchdog/sama5d4_wdt.c              |   1 +
 drivers/watchdog/sirfsoc_wdt.c              |   1 +
 drivers/watchdog/softdog.c                  |   1 +
 drivers/watchdog/sp5100_tco.c               |   1 +
 drivers/watchdog/sprd_wdt.c                 |   1 +
 drivers/watchdog/st_lpc_wdt.c               |   1 +
 drivers/watchdog/stmp3xxx_rtc_wdt.c         |   1 +
 drivers/watchdog/stpmic1_wdt.c              |   1 +
 drivers/watchdog/sunxi_wdt.c                |   1 +
 drivers/watchdog/tangox_wdt.c               |   1 +
 drivers/watchdog/tegra_wdt.c                |   1 +
 drivers/watchdog/tqmx86_wdt.c               |   1 +
 drivers/watchdog/ts4800_wdt.c               |   1 +
 drivers/watchdog/ts72xx_wdt.c               |   1 +
 drivers/watchdog/twl4030_wdt.c              |   1 +
 drivers/watchdog/uniphier_wdt.c             |   1 +
 drivers/watchdog/via_wdt.c                  |   1 +
 drivers/watchdog/w83627hf_wdt.c             |   1 +
 drivers/watchdog/watchdog_core.c            |  10 +-
 drivers/watchdog/wdat_wdt.c                 |   1 +
 drivers/watchdog/wm831x_wdt.c               |   1 +
 drivers/watchdog/wm8350_wdt.c               |   1 +
 drivers/watchdog/xen_wdt.c                  |   1 +
 drivers/watchdog/ziirave_wdt.c              |   1 +
 include/asm-generic/export.h                |  14 +-
 include/linux/export.h                      |  92 +++++++++++--
 include/linux/module.h                      |   2 +
 init/Kconfig                                |  13 ++
 kernel/module.c                             |  67 +++++++++-
 scripts/Makefile.modpost                    |   4 +-
 scripts/coccinelle/misc/add_namespace.cocci |  23 ++++
 scripts/mod/modpost.c                       | 137 ++++++++++++++++++--
 scripts/mod/modpost.h                       |   9 ++
 scripts/nsdeps                              |  56 ++++++++
 114 files changed, 504 insertions(+), 46 deletions(-)
 create mode 100644 scripts/coccinelle/misc/add_namespace.cocci
 create mode 100644 scripts/nsdeps

-- 
2.23.0.rc1.153.gdeed80330f-goog

^ permalink raw reply	[flat|nested] 11+ messages in thread

[parent not found: <20190821114955.12788-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>]

* [PATCH v3 11/11] RFC: watchdog: export core symbols in WATCHDOG_CORE namespace
       [not found]     ` <20190821114955.12788-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
@ 2019-08-21 11:49       ` Matthias Maennich
       [not found]         ` <20190821114955.12788-12-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
  2019-08-21 12:46       ` [PATCH v3 00/11] Symbol Namespaces Nicolas Pitre
  2019-08-21 13:11       ` Peter Zijlstra
  2 siblings, 1 reply; 11+ messages in thread
From: Matthias Maennich @ 2019-08-21 11:49 UTC (permalink / raw)
  To: linux-kernel-u79uwXL29TY76Z2rM5mHXA
  Cc: Tomer Maimon, lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w,
	linux-stm32-XDFAJ8BFU24N7RejjzZ/Li2xQDfSxrLKVpNB7YpNyf8,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Kevin Hilman,
	Michal Simek, Ludovic Desroches, mingo-H+wXaHxf7aLQT0dZR+AlfA,
	geert-Td1EMuHUCqxL1ZNQvxDV9g, NXP Linux Team, Tomas Winkler,
	Guenter Roeck, Jean Delvare, Sascha Hauer,
	maennich-hpIqsD4AKlfQT0dZR+AlfA, tglx-hfZtesqFncYOwBW4kG4KsQ,
	michal.lkml-yyZNWGI4GtDR7s880joybQ, Scott Branden, Andrew Jeffery,
	gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r,
	linux-usb-u79uwXL29TY76Z2rM5mHXA, Pengutronix Kernel Team,
	Alexandre Belloni, linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A, Th

Modules using these symbols are required to explicitly import the
namespace. This patch was generated with the following steps and serves
as a reference to use the symbol namespace feature:

 1) Use EXPORT_SYMBOL_NS* macros instead of EXPORT_SYMBOL* for symbols
    in watchdog_core.c
 2) make  (see warnings during modpost about missing imports)
 3) make nsdeps

I used 'allmodconfig' for the above steps to ensure all occurrences are
patched.

Defining DEFAULT_SYMBOL_NAMESPACE in the Makefile is not trivial in this
case as not only watchdog_core is defined in drivers/watchdog/Makefile.
Hence this patch uses the variant of using the EXPORT_SYMBOL_NS* macros
to export into a different namespace.

An alternative to this patch would be a single definition line before
any use of EXPORT_SYMBOL*:
 #define DEFAULT_SYMBOL_NAMESPACE WATCHDOG_CORE

Signed-off-by: Matthias Maennich <maennich@google.com>
---
 drivers/hwmon/ftsteutates.c         |  1 +
 drivers/hwmon/sch56xx-common.c      |  1 +
 drivers/rtc/rtc-abx80x.c            |  1 +
 drivers/watchdog/armada_37xx_wdt.c  |  1 +
 drivers/watchdog/asm9260_wdt.c      |  1 +
 drivers/watchdog/aspeed_wdt.c       |  1 +
 drivers/watchdog/at91sam9_wdt.c     |  1 +
 drivers/watchdog/atlas7_wdt.c       |  1 +
 drivers/watchdog/bcm2835_wdt.c      |  1 +
 drivers/watchdog/bcm47xx_wdt.c      |  1 +
 drivers/watchdog/bcm7038_wdt.c      |  1 +
 drivers/watchdog/bcm_kona_wdt.c     |  1 +
 drivers/watchdog/bd70528_wdt.c      |  1 +
 drivers/watchdog/cadence_wdt.c      |  1 +
 drivers/watchdog/da9052_wdt.c       |  1 +
 drivers/watchdog/da9055_wdt.c       |  1 +
 drivers/watchdog/da9062_wdt.c       |  1 +
 drivers/watchdog/da9063_wdt.c       |  1 +
 drivers/watchdog/davinci_wdt.c      |  1 +
 drivers/watchdog/digicolor_wdt.c    |  1 +
 drivers/watchdog/dw_wdt.c           |  1 +
 drivers/watchdog/ebc-c384_wdt.c     |  1 +
 drivers/watchdog/ep93xx_wdt.c       |  1 +
 drivers/watchdog/ftwdt010_wdt.c     |  1 +
 drivers/watchdog/gpio_wdt.c         |  1 +
 drivers/watchdog/hpwdt.c            |  1 +
 drivers/watchdog/i6300esb.c         |  1 +
 drivers/watchdog/iTCO_wdt.c         |  1 +
 drivers/watchdog/ie6xx_wdt.c        |  1 +
 drivers/watchdog/imgpdc_wdt.c       |  1 +
 drivers/watchdog/imx2_wdt.c         |  1 +
 drivers/watchdog/intel-mid_wdt.c    |  1 +
 drivers/watchdog/it87_wdt.c         |  1 +
 drivers/watchdog/kempld_wdt.c       |  1 +
 drivers/watchdog/lpc18xx_wdt.c      |  1 +
 drivers/watchdog/max63xx_wdt.c      |  1 +
 drivers/watchdog/max77620_wdt.c     |  1 +
 drivers/watchdog/mei_wdt.c          |  1 +
 drivers/watchdog/mena21_wdt.c       |  1 +
 drivers/watchdog/menf21bmc_wdt.c    |  1 +
 drivers/watchdog/menz69_wdt.c       |  1 +
 drivers/watchdog/meson_gxbb_wdt.c   |  1 +
 drivers/watchdog/meson_wdt.c        |  1 +
 drivers/watchdog/mlx_wdt.c          |  1 +
 drivers/watchdog/moxart_wdt.c       |  1 +
 drivers/watchdog/mtk_wdt.c          |  1 +
 drivers/watchdog/ni903x_wdt.c       |  1 +
 drivers/watchdog/nic7018_wdt.c      |  1 +
 drivers/watchdog/npcm_wdt.c         |  1 +
 drivers/watchdog/of_xilinx_wdt.c    |  1 +
 drivers/watchdog/omap_wdt.c         |  1 +
 drivers/watchdog/pm8916_wdt.c       |  1 +
 drivers/watchdog/qcom-wdt.c         |  1 +
 drivers/watchdog/rave-sp-wdt.c      |  1 +
 drivers/watchdog/renesas_wdt.c      |  1 +
 drivers/watchdog/retu_wdt.c         |  1 +
 drivers/watchdog/rn5t618_wdt.c      |  1 +
 drivers/watchdog/rza_wdt.c          |  1 +
 drivers/watchdog/s3c2410_wdt.c      |  1 +
 drivers/watchdog/sama5d4_wdt.c      |  1 +
 drivers/watchdog/sirfsoc_wdt.c      |  1 +
 drivers/watchdog/softdog.c          |  1 +
 drivers/watchdog/sp5100_tco.c       |  1 +
 drivers/watchdog/sprd_wdt.c         |  1 +
 drivers/watchdog/st_lpc_wdt.c       |  1 +
 drivers/watchdog/stmp3xxx_rtc_wdt.c |  1 +
 drivers/watchdog/stpmic1_wdt.c      |  1 +
 drivers/watchdog/sunxi_wdt.c        |  1 +
 drivers/watchdog/tangox_wdt.c       |  1 +
 drivers/watchdog/tegra_wdt.c        |  1 +
 drivers/watchdog/tqmx86_wdt.c       |  1 +
 drivers/watchdog/ts4800_wdt.c       |  1 +
 drivers/watchdog/ts72xx_wdt.c       |  1 +
 drivers/watchdog/twl4030_wdt.c      |  1 +
 drivers/watchdog/uniphier_wdt.c     |  1 +
 drivers/watchdog/via_wdt.c          |  1 +
 drivers/watchdog/w83627hf_wdt.c     |  1 +
 drivers/watchdog/watchdog_core.c    | 10 +++++-----
 drivers/watchdog/wdat_wdt.c         |  1 +
 drivers/watchdog/wm831x_wdt.c       |  1 +
 drivers/watchdog/wm8350_wdt.c       |  1 +
 drivers/watchdog/xen_wdt.c          |  1 +
 drivers/watchdog/ziirave_wdt.c      |  1 +
 83 files changed, 87 insertions(+), 5 deletions(-)

diff --git a/drivers/hwmon/ftsteutates.c b/drivers/hwmon/ftsteutates.c
index 371ce7745f5e..fa67f7c565be 100644
--- a/drivers/hwmon/ftsteutates.c
+++ b/drivers/hwmon/ftsteutates.c
@@ -830,3 +830,4 @@ module_i2c_driver(fts_driver);
 MODULE_AUTHOR("Thilo Cestonaro <thilo.cestonaro@ts.fujitsu.com>");
 MODULE_DESCRIPTION("FTS Teutates driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/hwmon/sch56xx-common.c b/drivers/hwmon/sch56xx-common.c
index 6c84780e358e..06dd840f3bf7 100644
--- a/drivers/hwmon/sch56xx-common.c
+++ b/drivers/hwmon/sch56xx-common.c
@@ -571,6 +571,7 @@ static void __exit sch56xx_exit(void)
 MODULE_DESCRIPTION("SMSC SCH56xx Hardware Monitoring Common Code");
 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 
 module_init(sch56xx_init);
 module_exit(sch56xx_exit);
diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c
index 73830670a41f..3ff3b96d14d7 100644
--- a/drivers/rtc/rtc-abx80x.c
+++ b/drivers/rtc/rtc-abx80x.c
@@ -880,3 +880,4 @@ MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>");
 MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
 MODULE_DESCRIPTION("Abracon ABX80X RTC driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/armada_37xx_wdt.c b/drivers/watchdog/armada_37xx_wdt.c
index e5dcb26d85f0..00e153ae70eb 100644
--- a/drivers/watchdog/armada_37xx_wdt.c
+++ b/drivers/watchdog/armada_37xx_wdt.c
@@ -370,4 +370,5 @@ MODULE_AUTHOR("Marek Behun <marek.behun@nic.cz>");
 MODULE_DESCRIPTION("Armada 37xx CPU Watchdog");
 
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:armada_37xx_wdt");
diff --git a/drivers/watchdog/asm9260_wdt.c b/drivers/watchdog/asm9260_wdt.c
index 45047e514b8e..fd7289df2cb3 100644
--- a/drivers/watchdog/asm9260_wdt.c
+++ b/drivers/watchdog/asm9260_wdt.c
@@ -374,3 +374,4 @@ module_platform_driver(asm9260_wdt_driver);
 MODULE_DESCRIPTION("asm9260 WatchDog Timer Driver");
 MODULE_AUTHOR("Oleksij Rempel <linux@rempel-privat.de>");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
index cc71861e033a..2607158965d6 100644
--- a/drivers/watchdog/aspeed_wdt.c
+++ b/drivers/watchdog/aspeed_wdt.c
@@ -334,3 +334,4 @@ module_exit(aspeed_wdt_exit);
 
 MODULE_DESCRIPTION("Aspeed Watchdog Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c
index 292b5a1ca831..e7aa31fe4336 100644
--- a/drivers/watchdog/at91sam9_wdt.c
+++ b/drivers/watchdog/at91sam9_wdt.c
@@ -416,3 +416,4 @@ module_platform_driver_probe(at91wdt_driver, at91wdt_probe);
 MODULE_AUTHOR("Renaud CERRATO <r.cerrato@til-technologies.fr>");
 MODULE_DESCRIPTION("Watchdog driver for Atmel AT91SAM9x processors");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/atlas7_wdt.c b/drivers/watchdog/atlas7_wdt.c
index 9bfe650d802f..f67e6f101102 100644
--- a/drivers/watchdog/atlas7_wdt.c
+++ b/drivers/watchdog/atlas7_wdt.c
@@ -218,4 +218,5 @@ module_platform_driver(atlas7_wdt_driver);
 MODULE_DESCRIPTION("CSRatlas7 watchdog driver");
 MODULE_AUTHOR("Guo Zeng <Guo.Zeng@csr.com>");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:atlas7-wdt");
diff --git a/drivers/watchdog/bcm2835_wdt.c b/drivers/watchdog/bcm2835_wdt.c
index dec6ca019bea..2f41b8a6e2f6 100644
--- a/drivers/watchdog/bcm2835_wdt.c
+++ b/drivers/watchdog/bcm2835_wdt.c
@@ -242,3 +242,4 @@ MODULE_ALIAS("platform:bcm2835-wdt");
 MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
 MODULE_DESCRIPTION("Driver for Broadcom BCM2835 watchdog timer");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/bcm47xx_wdt.c b/drivers/watchdog/bcm47xx_wdt.c
index 05425c1dfd4c..231009f01024 100644
--- a/drivers/watchdog/bcm47xx_wdt.c
+++ b/drivers/watchdog/bcm47xx_wdt.c
@@ -241,3 +241,4 @@ MODULE_AUTHOR("Aleksandar Radovanovic");
 MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>");
 MODULE_DESCRIPTION("Watchdog driver for Broadcom BCM47xx");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/bcm7038_wdt.c b/drivers/watchdog/bcm7038_wdt.c
index 979caa18d3c8..e66184997775 100644
--- a/drivers/watchdog/bcm7038_wdt.c
+++ b/drivers/watchdog/bcm7038_wdt.c
@@ -212,5 +212,6 @@ module_param(nowayout, bool, 0);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_DESCRIPTION("Driver for Broadcom 7038 SoCs Watchdog");
 MODULE_AUTHOR("Justin Chen");
diff --git a/drivers/watchdog/bcm_kona_wdt.c b/drivers/watchdog/bcm_kona_wdt.c
index eb850a8d19df..5b5a6a76c1aa 100644
--- a/drivers/watchdog/bcm_kona_wdt.c
+++ b/drivers/watchdog/bcm_kona_wdt.c
@@ -339,3 +339,4 @@ MODULE_ALIAS("platform:" BCM_KONA_WDT_NAME);
 MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
 MODULE_DESCRIPTION("Broadcom Kona Watchdog Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/bd70528_wdt.c b/drivers/watchdog/bd70528_wdt.c
index b0152fef4fc7..790748a3a30a 100644
--- a/drivers/watchdog/bd70528_wdt.c
+++ b/drivers/watchdog/bd70528_wdt.c
@@ -288,3 +288,4 @@ module_platform_driver(bd70528_wdt);
 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
 MODULE_DESCRIPTION("BD70528 watchdog driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/cadence_wdt.c b/drivers/watchdog/cadence_wdt.c
index f8d4e91d0383..a44f3140656e 100644
--- a/drivers/watchdog/cadence_wdt.c
+++ b/drivers/watchdog/cadence_wdt.c
@@ -438,3 +438,4 @@ module_platform_driver(cdns_wdt_driver);
 MODULE_AUTHOR("Xilinx, Inc.");
 MODULE_DESCRIPTION("Watchdog driver for Cadence WDT");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/da9052_wdt.c b/drivers/watchdog/da9052_wdt.c
index d708c091bf1b..a5ceea0503bb 100644
--- a/drivers/watchdog/da9052_wdt.c
+++ b/drivers/watchdog/da9052_wdt.c
@@ -191,4 +191,5 @@ module_platform_driver(da9052_wdt_driver);
 MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");
 MODULE_DESCRIPTION("DA9052 SM Device Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:da9052-watchdog");
diff --git a/drivers/watchdog/da9055_wdt.c b/drivers/watchdog/da9055_wdt.c
index 389a4bdd208c..05b075f2ea90 100644
--- a/drivers/watchdog/da9055_wdt.c
+++ b/drivers/watchdog/da9055_wdt.c
@@ -166,4 +166,5 @@ module_platform_driver(da9055_wdt_driver);
 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 MODULE_DESCRIPTION("DA9055 watchdog");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:da9055-watchdog");
diff --git a/drivers/watchdog/da9062_wdt.c b/drivers/watchdog/da9062_wdt.c
index e149e66a6ea9..dfc2025d36ba 100644
--- a/drivers/watchdog/da9062_wdt.c
+++ b/drivers/watchdog/da9062_wdt.c
@@ -232,4 +232,5 @@ module_platform_driver(da9062_wdt_driver);
 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
 MODULE_DESCRIPTION("WDT device driver for Dialog DA9062 and DA9061");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:da9062-watchdog");
diff --git a/drivers/watchdog/da9063_wdt.c b/drivers/watchdog/da9063_wdt.c
index 3d65e92a4e3f..ae0cb7011762 100644
--- a/drivers/watchdog/da9063_wdt.c
+++ b/drivers/watchdog/da9063_wdt.c
@@ -239,4 +239,5 @@ module_platform_driver(da9063_wdt_driver);
 MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
 MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);
diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c
index 2b3f3cd382ef..4fa01dfa4edb 100644
--- a/drivers/watchdog/davinci_wdt.c
+++ b/drivers/watchdog/davinci_wdt.c
@@ -274,4 +274,5 @@ MODULE_PARM_DESC(heartbeat,
 		 __MODULE_STRING(DEFAULT_HEARTBEAT));
 
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:davinci-wdt");
diff --git a/drivers/watchdog/digicolor_wdt.c b/drivers/watchdog/digicolor_wdt.c
index 073d37867f47..ed86cf879dae 100644
--- a/drivers/watchdog/digicolor_wdt.c
+++ b/drivers/watchdog/digicolor_wdt.c
@@ -161,3 +161,4 @@ module_platform_driver(dc_wdt_driver);
 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 MODULE_DESCRIPTION("Driver for Conexant Digicolor watchdog timer");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
index fef7c61f5555..e98ccb38eb1d 100644
--- a/drivers/watchdog/dw_wdt.c
+++ b/drivers/watchdog/dw_wdt.c
@@ -340,3 +340,4 @@ module_platform_driver(dw_wdt_driver);
 MODULE_AUTHOR("Jamie Iles");
 MODULE_DESCRIPTION("Synopsys DesignWare Watchdog Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/ebc-c384_wdt.c b/drivers/watchdog/ebc-c384_wdt.c
index 8ef4b0df3855..7e4349472745 100644
--- a/drivers/watchdog/ebc-c384_wdt.c
+++ b/drivers/watchdog/ebc-c384_wdt.c
@@ -139,4 +139,5 @@ module_exit(ebc_c384_wdt_exit);
 MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
 MODULE_DESCRIPTION("WinSystems EBC-C384 watchdog timer driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("isa:" MODULE_NAME);
diff --git a/drivers/watchdog/ep93xx_wdt.c b/drivers/watchdog/ep93xx_wdt.c
index 38e26f160b9a..edfa422896d7 100644
--- a/drivers/watchdog/ep93xx_wdt.c
+++ b/drivers/watchdog/ep93xx_wdt.c
@@ -144,3 +144,4 @@ MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
 MODULE_DESCRIPTION("EP93xx Watchdog");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/ftwdt010_wdt.c b/drivers/watchdog/ftwdt010_wdt.c
index 21dcc7765688..c19186bc00b6 100644
--- a/drivers/watchdog/ftwdt010_wdt.c
+++ b/drivers/watchdog/ftwdt010_wdt.c
@@ -227,3 +227,4 @@ module_platform_driver(ftwdt010_wdt_driver);
 MODULE_AUTHOR("Linus Walleij");
 MODULE_DESCRIPTION("Watchdog driver for Faraday Technology FTWDT010");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/gpio_wdt.c b/drivers/watchdog/gpio_wdt.c
index 0923201ce874..6a90a7ecadeb 100644
--- a/drivers/watchdog/gpio_wdt.c
+++ b/drivers/watchdog/gpio_wdt.c
@@ -194,3 +194,4 @@ module_platform_driver(gpio_wdt_driver);
 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
 MODULE_DESCRIPTION("GPIO Watchdog");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c
index 7d34bcf1c45b..fb4d228a0d7e 100644
--- a/drivers/watchdog/hpwdt.c
+++ b/drivers/watchdog/hpwdt.c
@@ -386,6 +386,7 @@ static struct pci_driver hpwdt_driver = {
 MODULE_AUTHOR("Tom Mingarelli");
 MODULE_DESCRIPTION("hpe watchdog driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_VERSION(HPWDT_VERSION);
 
 module_param(soft_margin, int, 0);
diff --git a/drivers/watchdog/i6300esb.c b/drivers/watchdog/i6300esb.c
index a30835f547b3..700a8c6cae00 100644
--- a/drivers/watchdog/i6300esb.c
+++ b/drivers/watchdog/i6300esb.c
@@ -351,3 +351,4 @@ module_pci_driver(esb_driver);
 MODULE_AUTHOR("Ross Biro and David Härdeman");
 MODULE_DESCRIPTION("Watchdog driver for Intel 6300ESB chipsets");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index c559f706ae7e..454d8ff3edc1 100644
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -632,4 +632,5 @@ MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
 MODULE_DESCRIPTION("Intel TCO WatchDog Timer Driver");
 MODULE_VERSION(DRV_VERSION);
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:" DRV_NAME);
diff --git a/drivers/watchdog/ie6xx_wdt.c b/drivers/watchdog/ie6xx_wdt.c
index 8f28993fab8b..76bcff28eaf9 100644
--- a/drivers/watchdog/ie6xx_wdt.c
+++ b/drivers/watchdog/ie6xx_wdt.c
@@ -314,4 +314,5 @@ module_exit(ie6xx_wdt_exit);
 MODULE_AUTHOR("Alexander Stein <alexander.stein@systec-electronic.com>");
 MODULE_DESCRIPTION("Intel Atom E6xx Watchdog Device Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:" DRIVER_NAME);
diff --git a/drivers/watchdog/imgpdc_wdt.c b/drivers/watchdog/imgpdc_wdt.c
index b57ff3787052..6fe0fd7c0719 100644
--- a/drivers/watchdog/imgpdc_wdt.c
+++ b/drivers/watchdog/imgpdc_wdt.c
@@ -314,3 +314,4 @@ MODULE_AUTHOR("Jude Abraham <Jude.Abraham@imgtec.com>");
 MODULE_AUTHOR("Naidu Tellapati <Naidu.Tellapati@imgtec.com>");
 MODULE_DESCRIPTION("Imagination Technologies PDC Watchdog Timer Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index 32af3974e6bb..dc6d4132ec1f 100644
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -433,4 +433,5 @@ module_platform_driver_probe(imx2_wdt_driver, imx2_wdt_probe);
 MODULE_AUTHOR("Wolfram Sang");
 MODULE_DESCRIPTION("Watchdog driver for IMX2 and later");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:" DRIVER_NAME);
diff --git a/drivers/watchdog/intel-mid_wdt.c b/drivers/watchdog/intel-mid_wdt.c
index 2cdbd37c700c..b859fd6d263b 100644
--- a/drivers/watchdog/intel-mid_wdt.c
+++ b/drivers/watchdog/intel-mid_wdt.c
@@ -181,3 +181,4 @@ module_platform_driver(mid_wdt_driver);
 MODULE_AUTHOR("David Cohen <david.a.cohen@linux.intel.com>");
 MODULE_DESCRIPTION("Watchdog Driver for Intel MID platform");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/it87_wdt.c b/drivers/watchdog/it87_wdt.c
index a4b71ebc8cab..610f5cdebf72 100644
--- a/drivers/watchdog/it87_wdt.c
+++ b/drivers/watchdog/it87_wdt.c
@@ -354,3 +354,4 @@ module_exit(it87_wdt_exit);
 MODULE_AUTHOR("Oliver Schuster");
 MODULE_DESCRIPTION("Hardware Watchdog Device Driver for IT87xx EC-LPC I/O");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/kempld_wdt.c b/drivers/watchdog/kempld_wdt.c
index 40bd518ed873..20a40e221dbb 100644
--- a/drivers/watchdog/kempld_wdt.c
+++ b/drivers/watchdog/kempld_wdt.c
@@ -550,3 +550,4 @@ module_platform_driver(kempld_wdt_driver);
 MODULE_DESCRIPTION("KEM PLD Watchdog Driver");
 MODULE_AUTHOR("Michael Brunner <michael.brunner@kontron.com>");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/lpc18xx_wdt.c b/drivers/watchdog/lpc18xx_wdt.c
index 78cf11c94941..4e34a4bd0b24 100644
--- a/drivers/watchdog/lpc18xx_wdt.c
+++ b/drivers/watchdog/lpc18xx_wdt.c
@@ -316,3 +316,4 @@ module_platform_driver(lpc18xx_wdt_driver);
 MODULE_AUTHOR("Ariel D'Alessandro <ariel@vanguardiasur.com.ar>");
 MODULE_DESCRIPTION("NXP LPC18xx Watchdog Timer Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/max63xx_wdt.c b/drivers/watchdog/max63xx_wdt.c
index 3a899628a834..053c9285adac 100644
--- a/drivers/watchdog/max63xx_wdt.c
+++ b/drivers/watchdog/max63xx_wdt.c
@@ -284,3 +284,4 @@ MODULE_PARM_DESC(nodelay,
 		 "(max6373/74 only, default=0)");
 
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/max77620_wdt.c b/drivers/watchdog/max77620_wdt.c
index be6a53c30002..304817d379a7 100644
--- a/drivers/watchdog/max77620_wdt.c
+++ b/drivers/watchdog/max77620_wdt.c
@@ -209,3 +209,4 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
 
 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/mei_wdt.c b/drivers/watchdog/mei_wdt.c
index 5391bf3e6b11..5e03226cada1 100644
--- a/drivers/watchdog/mei_wdt.c
+++ b/drivers/watchdog/mei_wdt.c
@@ -662,4 +662,5 @@ module_mei_cl_driver(mei_wdt_driver);
 
 MODULE_AUTHOR("Intel Corporation");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_DESCRIPTION("Device driver for Intel MEI iAMT watchdog");
diff --git a/drivers/watchdog/mena21_wdt.c b/drivers/watchdog/mena21_wdt.c
index 99d2359d5a8a..b759c66f1446 100644
--- a/drivers/watchdog/mena21_wdt.c
+++ b/drivers/watchdog/mena21_wdt.c
@@ -225,4 +225,5 @@ module_platform_driver(a21_wdt_driver);
 MODULE_AUTHOR("MEN Mikro Elektronik");
 MODULE_DESCRIPTION("MEN A21 Watchdog");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:a21-watchdog");
diff --git a/drivers/watchdog/menf21bmc_wdt.c b/drivers/watchdog/menf21bmc_wdt.c
index 81ebdfc371f4..358881618e2f 100644
--- a/drivers/watchdog/menf21bmc_wdt.c
+++ b/drivers/watchdog/menf21bmc_wdt.c
@@ -181,4 +181,5 @@ module_platform_driver(menf21bmc_wdt);
 MODULE_DESCRIPTION("MEN 14F021P00 BMC Watchdog driver");
 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:menf21bmc_wdt");
diff --git a/drivers/watchdog/menz69_wdt.c b/drivers/watchdog/menz69_wdt.c
index ed18238c5407..d13fcfc0f59c 100644
--- a/drivers/watchdog/menz69_wdt.c
+++ b/drivers/watchdog/menz69_wdt.c
@@ -167,4 +167,5 @@ module_mcb_driver(men_z069_driver);
 
 MODULE_AUTHOR("Johannes Thumshirn <jth@kernel.org>");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("mcb:16z069");
diff --git a/drivers/watchdog/meson_gxbb_wdt.c b/drivers/watchdog/meson_gxbb_wdt.c
index d17c1a6ed723..f30f85380679 100644
--- a/drivers/watchdog/meson_gxbb_wdt.c
+++ b/drivers/watchdog/meson_gxbb_wdt.c
@@ -204,3 +204,4 @@ module_platform_driver(meson_gxbb_wdt_driver);
 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
 MODULE_DESCRIPTION("Amlogic Meson GXBB Watchdog timer driver");
 MODULE_LICENSE("Dual BSD/GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/meson_wdt.c b/drivers/watchdog/meson_wdt.c
index 459f3ae02c91..0d60bb5aa688 100644
--- a/drivers/watchdog/meson_wdt.c
+++ b/drivers/watchdog/meson_wdt.c
@@ -228,5 +228,6 @@ MODULE_PARM_DESC(nowayout,
 		 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
 MODULE_DESCRIPTION("Meson Watchdog Timer Driver");
diff --git a/drivers/watchdog/mlx_wdt.c b/drivers/watchdog/mlx_wdt.c
index 03b9ac4b99af..2df48a6ed04b 100644
--- a/drivers/watchdog/mlx_wdt.c
+++ b/drivers/watchdog/mlx_wdt.c
@@ -287,4 +287,5 @@ module_platform_driver(mlxreg_wdt_driver);
 MODULE_AUTHOR("Michael Shych <michaelsh@mellanox.com>");
 MODULE_DESCRIPTION("Mellanox watchdog driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:mlx-wdt");
diff --git a/drivers/watchdog/moxart_wdt.c b/drivers/watchdog/moxart_wdt.c
index 6340a1f5f471..02dbfe2accfa 100644
--- a/drivers/watchdog/moxart_wdt.c
+++ b/drivers/watchdog/moxart_wdt.c
@@ -164,4 +164,5 @@ MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds");
 
 MODULE_DESCRIPTION("MOXART watchdog driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");
diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
index 9c3d0033260d..074c04324738 100644
--- a/drivers/watchdog/mtk_wdt.c
+++ b/drivers/watchdog/mtk_wdt.c
@@ -247,6 +247,7 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 			__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_AUTHOR("Matthias Brugger <matthias.bgg@gmail.com>");
 MODULE_DESCRIPTION("Mediatek WatchDog Timer Driver");
 MODULE_VERSION(DRV_VERSION);
diff --git a/drivers/watchdog/ni903x_wdt.c b/drivers/watchdog/ni903x_wdt.c
index 4cebad324b20..724d47f2f325 100644
--- a/drivers/watchdog/ni903x_wdt.c
+++ b/drivers/watchdog/ni903x_wdt.c
@@ -255,3 +255,4 @@ MODULE_DESCRIPTION("NI 903x Watchdog");
 MODULE_AUTHOR("Jeff Westfahl <jeff.westfahl@ni.com>");
 MODULE_AUTHOR("Kyle Roeschley <kyle.roeschley@ni.com>");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/nic7018_wdt.c b/drivers/watchdog/nic7018_wdt.c
index 2a46cc662943..efe0f188c79a 100644
--- a/drivers/watchdog/nic7018_wdt.c
+++ b/drivers/watchdog/nic7018_wdt.c
@@ -250,3 +250,4 @@ module_platform_driver(watchdog_driver);
 MODULE_DESCRIPTION("National Instruments NIC7018 Watchdog driver");
 MODULE_AUTHOR("Hui Chun Ong <hui.chun.ong@ni.com>");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/npcm_wdt.c b/drivers/watchdog/npcm_wdt.c
index 9c773c3d6d5d..aa2022a44985 100644
--- a/drivers/watchdog/npcm_wdt.c
+++ b/drivers/watchdog/npcm_wdt.c
@@ -248,3 +248,4 @@ module_platform_driver(npcm_wdt_driver);
 MODULE_AUTHOR("Joel Stanley");
 MODULE_DESCRIPTION("Watchdog driver for NPCM");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/of_xilinx_wdt.c b/drivers/watchdog/of_xilinx_wdt.c
index 7fe4f7c3f7ce..8d93e2089c6d 100644
--- a/drivers/watchdog/of_xilinx_wdt.c
+++ b/drivers/watchdog/of_xilinx_wdt.c
@@ -308,3 +308,4 @@ module_platform_driver(xwdt_driver);
 MODULE_AUTHOR("Alejandro Cabrera <aldaya@gmail.com>");
 MODULE_DESCRIPTION("Xilinx Watchdog driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
index 9b91882fe3c4..49565608924a 100644
--- a/drivers/watchdog/omap_wdt.c
+++ b/drivers/watchdog/omap_wdt.c
@@ -375,4 +375,5 @@ module_platform_driver(omap_wdt_driver);
 
 MODULE_AUTHOR("George G. Davis");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:omap_wdt");
diff --git a/drivers/watchdog/pm8916_wdt.c b/drivers/watchdog/pm8916_wdt.c
index 2d3652004e39..f13c1c2bec07 100644
--- a/drivers/watchdog/pm8916_wdt.c
+++ b/drivers/watchdog/pm8916_wdt.c
@@ -210,3 +210,4 @@ module_platform_driver(pm8916_wdt_driver);
 MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>");
 MODULE_DESCRIPTION("Qualcomm pm8916 watchdog driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c
index 7be7f87be28f..1ae02d3b5cb2 100644
--- a/drivers/watchdog/qcom-wdt.c
+++ b/drivers/watchdog/qcom-wdt.c
@@ -272,3 +272,4 @@ module_platform_driver(qcom_watchdog_driver);
 
 MODULE_DESCRIPTION("QCOM KPSS Watchdog Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/rave-sp-wdt.c b/drivers/watchdog/rave-sp-wdt.c
index 2c95615b6354..7fac3fabfcfb 100644
--- a/drivers/watchdog/rave-sp-wdt.c
+++ b/drivers/watchdog/rave-sp-wdt.c
@@ -329,6 +329,7 @@ module_platform_driver(rave_sp_wdt_driver);
 
 MODULE_DEVICE_TABLE(of, rave_sp_wdt_of_match);
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>");
 MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>");
 MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");
diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
index 00662a8e039c..ec5b1ec6c292 100644
--- a/drivers/watchdog/renesas_wdt.c
+++ b/drivers/watchdog/renesas_wdt.c
@@ -315,4 +315,5 @@ module_platform_driver(rwdt_driver);
 
 MODULE_DESCRIPTION("Renesas WDT Watchdog Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_AUTHOR("Wolfram Sang <wsa@sang-engineering.com>");
diff --git a/drivers/watchdog/retu_wdt.c b/drivers/watchdog/retu_wdt.c
index 258dfcf9cbda..6a3e2b8e5226 100644
--- a/drivers/watchdog/retu_wdt.c
+++ b/drivers/watchdog/retu_wdt.c
@@ -168,3 +168,4 @@ MODULE_DESCRIPTION("Retu watchdog");
 MODULE_AUTHOR("Amit Kucheria");
 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/rn5t618_wdt.c b/drivers/watchdog/rn5t618_wdt.c
index 234876047431..8f7bc6b1cb64 100644
--- a/drivers/watchdog/rn5t618_wdt.c
+++ b/drivers/watchdog/rn5t618_wdt.c
@@ -191,3 +191,4 @@ module_platform_driver(rn5t618_wdt_driver);
 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
 MODULE_DESCRIPTION("RN5T618 watchdog driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/rza_wdt.c b/drivers/watchdog/rza_wdt.c
index 7b6c365f7cd3..31ff9acc9af2 100644
--- a/drivers/watchdog/rza_wdt.c
+++ b/drivers/watchdog/rza_wdt.c
@@ -245,3 +245,4 @@ module_platform_driver(rza_wdt_driver);
 MODULE_DESCRIPTION("Renesas RZ/A WDT Driver");
 MODULE_AUTHOR("Chris Brandt <chris.brandt@renesas.com>");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 2395f353e52d..5c1800d41411 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -739,3 +739,4 @@ module_platform_driver(s3c2410wdt_driver);
 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>, Dimitry Andric <dimitry.andric@tomtom.com>");
 MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
index d193a60430b2..725f68703f1e 100644
--- a/drivers/watchdog/sama5d4_wdt.c
+++ b/drivers/watchdog/sama5d4_wdt.c
@@ -321,3 +321,4 @@ module_platform_driver(sama5d4_wdt_driver);
 MODULE_AUTHOR("Atmel Corporation");
 MODULE_DESCRIPTION("Atmel SAMA5D4 Watchdog Timer driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/sirfsoc_wdt.c b/drivers/watchdog/sirfsoc_wdt.c
index 734cf2966ecb..bcb75d9978f0 100644
--- a/drivers/watchdog/sirfsoc_wdt.c
+++ b/drivers/watchdog/sirfsoc_wdt.c
@@ -213,4 +213,5 @@ module_platform_driver(sirfsoc_wdt_driver);
 MODULE_DESCRIPTION("SiRF SoC watchdog driver");
 MODULE_AUTHOR("Xianglong Du <Xianglong.Du@csr.com>");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:sirfsoc-wdt");
diff --git a/drivers/watchdog/softdog.c b/drivers/watchdog/softdog.c
index 3e4885c1545e..8d50543f7340 100644
--- a/drivers/watchdog/softdog.c
+++ b/drivers/watchdog/softdog.c
@@ -165,3 +165,4 @@ module_exit(softdog_exit);
 MODULE_AUTHOR("Alan Cox");
 MODULE_DESCRIPTION("Software Watchdog Device Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c
index 93bd302ae7c5..716b9c43baf1 100644
--- a/drivers/watchdog/sp5100_tco.c
+++ b/drivers/watchdog/sp5100_tco.c
@@ -486,3 +486,4 @@ module_exit(sp5100_tco_exit);
 MODULE_AUTHOR("Priyanka Gupta");
 MODULE_DESCRIPTION("TCO timer driver for SP5100/SB800 chipset");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/sprd_wdt.c b/drivers/watchdog/sprd_wdt.c
index edba4e278685..55e883e8dcf4 100644
--- a/drivers/watchdog/sprd_wdt.c
+++ b/drivers/watchdog/sprd_wdt.c
@@ -384,3 +384,4 @@ module_platform_driver(sprd_watchdog_driver);
 MODULE_AUTHOR("Eric Long <eric.long@spreadtrum.com>");
 MODULE_DESCRIPTION("Spreadtrum Watchdog Timer Controller Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/st_lpc_wdt.c b/drivers/watchdog/st_lpc_wdt.c
index 14ab6559c748..4a7e6b4694fa 100644
--- a/drivers/watchdog/st_lpc_wdt.c
+++ b/drivers/watchdog/st_lpc_wdt.c
@@ -305,3 +305,4 @@ module_platform_driver(st_wdog_driver);
 MODULE_AUTHOR("David Paris <david.paris@st.com>");
 MODULE_DESCRIPTION("ST LPC Watchdog Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/stmp3xxx_rtc_wdt.c b/drivers/watchdog/stmp3xxx_rtc_wdt.c
index 7caf3aa71c6a..f1dd033c2b4b 100644
--- a/drivers/watchdog/stmp3xxx_rtc_wdt.c
+++ b/drivers/watchdog/stmp3xxx_rtc_wdt.c
@@ -150,4 +150,5 @@ module_platform_driver(stmp3xxx_wdt_driver);
 
 MODULE_DESCRIPTION("STMP3XXX RTC Watchdog Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
diff --git a/drivers/watchdog/stpmic1_wdt.c b/drivers/watchdog/stpmic1_wdt.c
index 45d0c543466f..6cdbe4bf5aaa 100644
--- a/drivers/watchdog/stpmic1_wdt.c
+++ b/drivers/watchdog/stpmic1_wdt.c
@@ -138,3 +138,4 @@ module_platform_driver(stpmic1_wdt_driver);
 MODULE_DESCRIPTION("Watchdog driver for STPMIC1 device");
 MODULE_AUTHOR("Pascal Paillet <p.paillet@st.com>");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/sunxi_wdt.c b/drivers/watchdog/sunxi_wdt.c
index 5f05a45ac187..dea10c79b817 100644
--- a/drivers/watchdog/sunxi_wdt.c
+++ b/drivers/watchdog/sunxi_wdt.c
@@ -289,6 +289,7 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
 		"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>");
 MODULE_AUTHOR("Henrik Nordstrom <henrik@henriknordstrom.net>");
 MODULE_DESCRIPTION("sunxi WatchDog Timer Driver");
diff --git a/drivers/watchdog/tangox_wdt.c b/drivers/watchdog/tangox_wdt.c
index 1afb0e9d808c..bc9025d31977 100644
--- a/drivers/watchdog/tangox_wdt.c
+++ b/drivers/watchdog/tangox_wdt.c
@@ -207,3 +207,4 @@ module_platform_driver(tangox_wdt_driver);
 MODULE_AUTHOR("Mans Rullgard <mans@mansr.com>");
 MODULE_DESCRIPTION("SMP86xx/SMP87xx Watchdog driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/tegra_wdt.c b/drivers/watchdog/tegra_wdt.c
index dfe06e506cad..06acd8251928 100644
--- a/drivers/watchdog/tegra_wdt.c
+++ b/drivers/watchdog/tegra_wdt.c
@@ -276,3 +276,4 @@ module_platform_driver(tegra_wdt_driver);
 MODULE_AUTHOR("NVIDIA Corporation");
 MODULE_DESCRIPTION("Tegra Watchdog Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/tqmx86_wdt.c b/drivers/watchdog/tqmx86_wdt.c
index 72d0b0adde38..35b8bfffa34d 100644
--- a/drivers/watchdog/tqmx86_wdt.c
+++ b/drivers/watchdog/tqmx86_wdt.c
@@ -124,3 +124,4 @@ MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
 MODULE_DESCRIPTION("TQMx86 Watchdog");
 MODULE_ALIAS("platform:tqmx86-wdt");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/ts4800_wdt.c b/drivers/watchdog/ts4800_wdt.c
index c137ad2bd5c3..b07f75f9049b 100644
--- a/drivers/watchdog/ts4800_wdt.c
+++ b/drivers/watchdog/ts4800_wdt.c
@@ -200,4 +200,5 @@ module_platform_driver(ts4800_wdt_driver);
 
 MODULE_AUTHOR("Damien Riegel <damien.riegel@savoirfairelinux.com>");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:ts4800_wdt");
diff --git a/drivers/watchdog/ts72xx_wdt.c b/drivers/watchdog/ts72xx_wdt.c
index bf918f5fa131..efd74cfabbf8 100644
--- a/drivers/watchdog/ts72xx_wdt.c
+++ b/drivers/watchdog/ts72xx_wdt.c
@@ -174,4 +174,5 @@ module_platform_driver(ts72xx_wdt_driver);
 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>");
 MODULE_DESCRIPTION("TS-72xx SBC Watchdog");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:ts72xx-wdt");
diff --git a/drivers/watchdog/twl4030_wdt.c b/drivers/watchdog/twl4030_wdt.c
index 355e428c0b99..98bcebe3a0b7 100644
--- a/drivers/watchdog/twl4030_wdt.c
+++ b/drivers/watchdog/twl4030_wdt.c
@@ -123,5 +123,6 @@ module_platform_driver(twl4030_wdt_driver);
 
 MODULE_AUTHOR("Nokia Corporation");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:twl4030_wdt");
 
diff --git a/drivers/watchdog/uniphier_wdt.c b/drivers/watchdog/uniphier_wdt.c
index 8e9242c23022..3a6d2d3a8f3c 100644
--- a/drivers/watchdog/uniphier_wdt.c
+++ b/drivers/watchdog/uniphier_wdt.c
@@ -255,3 +255,4 @@ MODULE_PARM_DESC(nowayout,
 MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
 MODULE_DESCRIPTION("UniPhier Watchdog Device Driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/via_wdt.c b/drivers/watchdog/via_wdt.c
index eeb39f96e72e..899a4fe1d7b6 100644
--- a/drivers/watchdog/via_wdt.c
+++ b/drivers/watchdog/via_wdt.c
@@ -259,3 +259,4 @@ module_pci_driver(wdt_driver);
 MODULE_AUTHOR("Marc Vertes");
 MODULE_DESCRIPTION("Driver for watchdog timer on VIA chipset");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/w83627hf_wdt.c b/drivers/watchdog/w83627hf_wdt.c
index 38b31e9947aa..b66aea20a96e 100644
--- a/drivers/watchdog/w83627hf_wdt.c
+++ b/drivers/watchdog/w83627hf_wdt.c
@@ -528,5 +528,6 @@ module_init(wdt_init);
 module_exit(wdt_exit);
 
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_AUTHOR("Pádraig  Brady <P@draigBrady.com>");
 MODULE_DESCRIPTION("w83627hf/thf WDT driver");
diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c
index 21e8085b848b..9deb22af5daa 100644
--- a/drivers/watchdog/watchdog_core.c
+++ b/drivers/watchdog/watchdog_core.c
@@ -145,7 +145,7 @@ int watchdog_init_timeout(struct watchdog_device *wdd,
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(watchdog_init_timeout);
+EXPORT_SYMBOL_NS_GPL(watchdog_init_timeout, WATCHDOG_CORE);
 
 static int watchdog_restart_notifier(struct notifier_block *nb,
 				     unsigned long action, void *data)
@@ -180,7 +180,7 @@ void watchdog_set_restart_priority(struct watchdog_device *wdd, int priority)
 {
 	wdd->restart_nb.priority = priority;
 }
-EXPORT_SYMBOL_GPL(watchdog_set_restart_priority);
+EXPORT_SYMBOL_NS_GPL(watchdog_set_restart_priority, WATCHDOG_CORE);
 
 static int __watchdog_register_device(struct watchdog_device *wdd)
 {
@@ -279,7 +279,7 @@ int watchdog_register_device(struct watchdog_device *wdd)
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(watchdog_register_device);
+EXPORT_SYMBOL_NS_GPL(watchdog_register_device, WATCHDOG_CORE);
 
 static void __watchdog_unregister_device(struct watchdog_device *wdd)
 {
@@ -311,7 +311,7 @@ void watchdog_unregister_device(struct watchdog_device *wdd)
 	mutex_unlock(&wtd_deferred_reg_mutex);
 }
 
-EXPORT_SYMBOL_GPL(watchdog_unregister_device);
+EXPORT_SYMBOL_NS_GPL(watchdog_unregister_device, WATCHDOG_CORE);
 
 static void devm_watchdog_unregister_device(struct device *dev, void *res)
 {
@@ -348,7 +348,7 @@ int devm_watchdog_register_device(struct device *dev,
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(devm_watchdog_register_device);
+EXPORT_SYMBOL_NS_GPL(devm_watchdog_register_device, WATCHDOG_CORE);
 
 static int __init watchdog_deferred_registration(void)
 {
diff --git a/drivers/watchdog/wdat_wdt.c b/drivers/watchdog/wdat_wdt.c
index e7cf41aa26c3..027339a557ce 100644
--- a/drivers/watchdog/wdat_wdt.c
+++ b/drivers/watchdog/wdat_wdt.c
@@ -523,4 +523,5 @@ module_platform_driver(wdat_wdt_driver);
 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
 MODULE_DESCRIPTION("ACPI Hardware Watchdog (WDAT) driver");
 MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:wdat_wdt");
diff --git a/drivers/watchdog/wm831x_wdt.c b/drivers/watchdog/wm831x_wdt.c
index 030ce240620d..a17e2ac251a1 100644
--- a/drivers/watchdog/wm831x_wdt.c
+++ b/drivers/watchdog/wm831x_wdt.c
@@ -282,4 +282,5 @@ module_platform_driver(wm831x_wdt_driver);
 MODULE_AUTHOR("Mark Brown");
 MODULE_DESCRIPTION("WM831x Watchdog");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:wm831x-watchdog");
diff --git a/drivers/watchdog/wm8350_wdt.c b/drivers/watchdog/wm8350_wdt.c
index 33c62d51f00a..f81e661662e6 100644
--- a/drivers/watchdog/wm8350_wdt.c
+++ b/drivers/watchdog/wm8350_wdt.c
@@ -175,4 +175,5 @@ module_platform_driver(wm8350_wdt_driver);
 MODULE_AUTHOR("Mark Brown");
 MODULE_DESCRIPTION("WM8350 Watchdog");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
 MODULE_ALIAS("platform:wm8350-wdt");
diff --git a/drivers/watchdog/xen_wdt.c b/drivers/watchdog/xen_wdt.c
index b343f421dc72..8b21a4b51047 100644
--- a/drivers/watchdog/xen_wdt.c
+++ b/drivers/watchdog/xen_wdt.c
@@ -206,3 +206,4 @@ module_exit(xen_wdt_cleanup_module);
 MODULE_AUTHOR("Jan Beulich <jbeulich@novell.com>");
 MODULE_DESCRIPTION("Xen WatchDog Timer Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
diff --git a/drivers/watchdog/ziirave_wdt.c b/drivers/watchdog/ziirave_wdt.c
index dec660c509b3..2d81c7b546f2 100644
--- a/drivers/watchdog/ziirave_wdt.c
+++ b/drivers/watchdog/ziirave_wdt.c
@@ -751,3 +751,4 @@ module_i2c_driver(ziirave_wdt_driver);
 MODULE_AUTHOR("Martyn Welch <martyn.welch@collabora.co.uk");
 MODULE_DESCRIPTION("Zodiac Aerospace RAVE Switch Watchdog Processor Driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(WATCHDOG_CORE);
-- 
2.23.0.rc1.153.gdeed80330f-goog


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^ permalink raw reply related	[flat|nested] 11+ messages in thread

[parent not found: <20190821114955.12788-12-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>]

* Re: [PATCH v3 11/11] RFC: watchdog: export core symbols in WATCHDOG_CORE namespace
       [not found]         ` <20190821114955.12788-12-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
@ 2019-08-21 12:39           ` Greg KH
  2019-08-21 14:59           ` Guenter Roeck
  1 sibling, 0 replies; 11+ messages in thread
From: Greg KH @ 2019-08-21 12:39 UTC (permalink / raw)
  To: Matthias Maennich
  Cc: Tomer Maimon, lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w,
	linux-stm32-XDFAJ8BFU24N7RejjzZ/Li2xQDfSxrLKVpNB7YpNyf8,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Kevin Hilman,
	Michal Simek, Ludovic Desroches, mingo-H+wXaHxf7aLQT0dZR+AlfA,
	geert-Td1EMuHUCqxL1ZNQvxDV9g, NXP Linux Team, Tomas Winkler,
	Guenter Roeck, Jean Delvare, Sascha Hauer,
	tglx-hfZtesqFncYOwBW4kG4KsQ, michal.lkml-yyZNWGI4GtDR7s880joybQ,
	Scott Branden, Andrew Jeffery, linux-usb-u79uwXL29TY76Z2rM5mHXA,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA, Pengutronix Kernel Team,
	Alexandre Belloni, linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A,
	Thierry Reding <thier>

On Wed, Aug 21, 2019 at 12:49:26PM +0100, Matthias Maennich wrote:
> Modules using these symbols are required to explicitly import the
> namespace. This patch was generated with the following steps and serves
> as a reference to use the symbol namespace feature:
> 
>  1) Use EXPORT_SYMBOL_NS* macros instead of EXPORT_SYMBOL* for symbols
>     in watchdog_core.c
>  2) make  (see warnings during modpost about missing imports)
>  3) make nsdeps
> 
> I used 'allmodconfig' for the above steps to ensure all occurrences are
> patched.
> 
> Defining DEFAULT_SYMBOL_NAMESPACE in the Makefile is not trivial in this
> case as not only watchdog_core is defined in drivers/watchdog/Makefile.
> Hence this patch uses the variant of using the EXPORT_SYMBOL_NS* macros
> to export into a different namespace.
> 
> An alternative to this patch would be a single definition line before
> any use of EXPORT_SYMBOL*:
>  #define DEFAULT_SYMBOL_NAMESPACE WATCHDOG_CORE
> 
> Signed-off-by: Matthias Maennich <maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>

As we talked in chat, the cc: list for this patch was crazy :)

If you end up resending this (as odds are the mailing lists will trash
it for too many recipients), feel free to add:

Reviewed-by: Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>

Great work,

greg k-h

^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 11/11] RFC: watchdog: export core symbols in WATCHDOG_CORE namespace
       [not found]         ` <20190821114955.12788-12-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
  2019-08-21 12:39           ` Greg KH
@ 2019-08-21 14:59           ` Guenter Roeck
       [not found]             ` <20190821145911.GA6521-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org>
  1 sibling, 1 reply; 11+ messages in thread
From: Guenter Roeck @ 2019-08-21 14:59 UTC (permalink / raw)
  To: Matthias Maennich
  Cc: Tomer Maimon, lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w,
	linux-stm32-XDFAJ8BFU24N7RejjzZ/Li2xQDfSxrLKVpNB7YpNyf8,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Kevin Hilman,
	Michal Simek, Ludovic Desroches, mingo-H+wXaHxf7aLQT0dZR+AlfA,
	geert-Td1EMuHUCqxL1ZNQvxDV9g, NXP Linux Team, Tomas Winkler,
	Jean Delvare, Sascha Hauer, tglx-hfZtesqFncYOwBW4kG4KsQ,
	michal.lkml-yyZNWGI4GtDR7s880joybQ, Scott Branden, Andrew Jeffery,
	gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r,
	linux-usb-u79uwXL29TY76Z2rM5mHXA,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA, Pengutronix Kernel Team,
	Alexandre Belloni, linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A,
	Thierry Reding <thierry.redin>

On Wed, Aug 21, 2019 at 12:49:26PM +0100, Matthias Maennich wrote:
> Modules using these symbols are required to explicitly import the
> namespace. This patch was generated with the following steps and serves
> as a reference to use the symbol namespace feature:
> 
>  1) Use EXPORT_SYMBOL_NS* macros instead of EXPORT_SYMBOL* for symbols
>     in watchdog_core.c
>  2) make  (see warnings during modpost about missing imports)
>  3) make nsdeps
> 
> I used 'allmodconfig' for the above steps to ensure all occurrences are
> patched.
> 
> Defining DEFAULT_SYMBOL_NAMESPACE in the Makefile is not trivial in this
> case as not only watchdog_core is defined in drivers/watchdog/Makefile.
> Hence this patch uses the variant of using the EXPORT_SYMBOL_NS* macros
> to export into a different namespace.
> 
I don't have the context, and thus I am missing the point of this patch
set. Whatever it is supposed to accomplish, it seems extreme to me
to require extra code in each driver for it.

Anyway, WATCHDOG_CORE would be the default namespace (if it is what
I think it is) for watchdog drivers, even though not all watchdog drivers
use it. As such, I am missing an explanation why defining it in Makefile
is not trivial. "... as not only watchdog_core is defined in
drivers/watchdog/Makefile" does not mean anything to me and is not a real
explanation. Also, it is not immediately obvious to me why "select
WATCHDOG_CORE" in Kconfig would not automatically imply that WATCHDOG_CORE
is used by a given driver, and why it is impossible to use that
information to avoid the per-driver changes.

I am also missing an explanation why WATCHDOG_CORE is going to be a
separate namespace to start with. Maybe that discussion has happened,
but I don't recall being advised or asked or told about it. Are we also
going to have a new HWMON_CORE namespace ? And the same for each other
subsystem in the kernel ?

Since this is being added to the watchdog API, it will have to be
documented accordingly. Watchdog driver writers, both inside and outside
the watchdog subsystem, will need to know that they now have to add an
additional boilerplate declaration into their drivers.

Last but not least, combining patches affecting multiple subsystems in a
single patch will make it difficult to apply and will likely result in
conflicts. Personally I would prefer a split into one patch per affected
subsystem. Also, please keep in mind that new pending watchdog drivers
won't have the new boilerplate.

Thanks,
Guenter

^ permalink raw reply	[flat|nested] 11+ messages in thread

[parent not found: <20190821145911.GA6521-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org>]

* Re: [PATCH v3 11/11] RFC: watchdog: export core symbols in WATCHDOG_CORE namespace
       [not found]             ` <20190821145911.GA6521-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org>
@ 2019-08-21 16:28               ` Matthias Maennich
  0 siblings, 0 replies; 11+ messages in thread
From: Matthias Maennich @ 2019-08-21 16:28 UTC (permalink / raw)
  To: Guenter Roeck
  Cc: Tomer Maimon, lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w,
	linux-stm32-XDFAJ8BFU24N7RejjzZ/Li2xQDfSxrLKVpNB7YpNyf8,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Kevin Hilman,
	Michal Simek, Ludovic Desroches, mingo-H+wXaHxf7aLQT0dZR+AlfA,
	geert-Td1EMuHUCqxL1ZNQvxDV9g, NXP Linux Team, Tomas Winkler,
	Jean Delvare, Sascha Hauer, tglx-hfZtesqFncYOwBW4kG4KsQ,
	michal.lkml-yyZNWGI4GtDR7s880joybQ, Scott Branden, Andrew Jeffery,
	gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r,
	linux-usb-u79uwXL29TY76Z2rM5mHXA,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA, Pengutronix Kernel Team,
	Alexandre Belloni, linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A,
	Thierry Reding <thierry.redin>

Hi Guenter!

On Wed, 21 Aug, 07:59, Guenter Roeck wrote:
>On Wed, Aug 21, 2019 at 12:49:26PM +0100, Matthias Maennich wrote:
>> Modules using these symbols are required to explicitly import the
>> namespace. This patch was generated with the following steps and serves
>> as a reference to use the symbol namespace feature:
>>
>>  1) Use EXPORT_SYMBOL_NS* macros instead of EXPORT_SYMBOL* for symbols
>>     in watchdog_core.c
>>  2) make  (see warnings during modpost about missing imports)
>>  3) make nsdeps
>>
>> I used 'allmodconfig' for the above steps to ensure all occurrences are
>> patched.
>>
>> Defining DEFAULT_SYMBOL_NAMESPACE in the Makefile is not trivial in this
>> case as not only watchdog_core is defined in drivers/watchdog/Makefile.
>> Hence this patch uses the variant of using the EXPORT_SYMBOL_NS* macros
>> to export into a different namespace.
>>
>I don't have the context, and thus I am missing the point of this patch
>set. Whatever it is supposed to accomplish, it seems extreme to me
>to require extra code in each driver for it.
>

Unfortunately, get_maintainer.pl has helped me too much and this series
got blocked by some mailing lists due to the large amount of recipients.
Following versions will be sent to the previous audience + the
linux-watchdog list.
For context, the full series (including previous versions) can be found
on lore at
https://lore.kernel.org/lkml/20180716122125.175792-1-maco-z5hGa2qSFaRBDgjK7y7TUQ@public.gmane.org/
and the cover letter for v3 has made it to linux-amlogic
https://lore.kernel.org/linux-amlogic/20190821114955.12788-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org/

>Anyway, WATCHDOG_CORE would be the default namespace (if it is what
>I think it is) for watchdog drivers, even though not all watchdog drivers
>use it. As such, I am missing an explanation why defining it in Makefile
>is not trivial. "... as not only watchdog_core is defined in
>drivers/watchdog/Makefile" does not mean anything to me and is not a real

True, that is a bit out of context. Especially considering you did not
receive any other messages of that series.
Defining a namespace a symbol should be exported to can be done in
different ways. All of them effectively change the EXPORT_SYMBOL*
macro's behaviour. The method I am referring to is using

  ccflags-y += -DDEFAULT_SYMBOL_NAMESPACE=WATCHDOG_CORE

directly in drivers/watchdog/Makefile. Since this would also apply the
namespace to exports in non-core modules it would be incorrect. Thus I
used the method of applying the namespace directly by changing the
EXPORT_SYMBOL macro expansion.

>explanation. Also, it is not immediately obvious to me why "select
>WATCHDOG_CORE" in Kconfig would not automatically imply that WATCHDOG_CORE
>is used by a given driver, and why it is impossible to use that
>information to avoid the per-driver changes.
>

One intention of this patch series is to make exporting and using of
namespaces explicit. As such, the subsystem exporting symbols is
defining the namespace it exports to and the module using a namespace is
supposed to explicitly declare its usage via import. In case of watchdog
(and probably other cases) it might make sense to find a way to
implicitly import the namespace for in-tree drivers in the same area.

>I am also missing an explanation why WATCHDOG_CORE is going to be a
>separate namespace to start with. Maybe that discussion has happened,
>but I don't recall being advised or asked or told about it. Are we also
>going to have a new HWMON_CORE namespace ? And the same for each other
>subsystem in the kernel ?
>

This very patch is an RFC to demonstrate how Symbol Namespaces would be
used based on the current implementation (the other RFC as part of this
series is for the introduction of the namespace USB_STORAGE).
WATCHDOG_CORE serves as one of two examples. I do not think the two RFC
patches should be merged along with this series.

>Since this is being added to the watchdog API, it will have to be
>documented accordingly. Watchdog driver writers, both inside and outside
>the watchdog subsystem, will need to know that they now have to add an
>additional boilerplate declaration into their drivers.
>

Completely agree. This is just an RFC that omits these details as it
purely focuses on the introduction and consequences of such a namespace
to demonstrate how the feature works.

>Last but not least, combining patches affecting multiple subsystems in a
>single patch will make it difficult to apply and will likely result in
>conflicts. Personally I would prefer a split into one patch per affected
>subsystem. Also, please keep in mind that new pending watchdog drivers
>won't have the new boilerplate.

I understand the point. Especially as I am already now affected by the
long list of recipients when sending this patch. The problem with single
patches here is, that once a symbol is exported into a namespace, all
modules using it have to declare that import to avoid a warning at
compile time and module load time. Hence the all-in-one approach.
Luckily, the patch series also provides a way to address such a warning
(via `make nsdeps`) that creates the necessary source code fix as a
single line per module and namespace right after MODULE_LICENSE(). That
is how this patch was created in the first place.

Cheers,
Matthias

^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 00/11] Symbol Namespaces
       [not found]     ` <20190821114955.12788-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
  2019-08-21 11:49       ` [PATCH v3 11/11] RFC: watchdog: export core symbols in WATCHDOG_CORE namespace Matthias Maennich
@ 2019-08-21 12:46       ` Nicolas Pitre
       [not found]         ` <nycvar.YSQ.7.76.1908210840490.19480-fMhRO7WWcppj+hNMo8g0rg@public.gmane.org>
  2019-08-21 13:11       ` Peter Zijlstra
  2 siblings, 1 reply; 11+ messages in thread
From: Nicolas Pitre @ 2019-08-21 12:46 UTC (permalink / raw)
  To: Matthias Maennich
  Cc: kstewart-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, oneukum-IBi9RG/b67k,
	linux-stm32-XDFAJ8BFU24N7RejjzZ/Li2xQDfSxrLKVpNB7YpNyf8,
	linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	usb-storage-ijkIwGHArpdIPJnuZ7Njw4oP9KaGy4wf, Toru Komatsu,
	Mauro Carvalho Chehab, Nicolas Ferre, David Howells,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A, Will Deacon,
	patches-yzvPICuk2AA4QjBA90+/kJqQE7yCjDx5, Michael Ellerman,
	hpa-YMNOUZJC4hwAvxtiuMwx3w, joel-QYYGw3jwrUn5owFQY34kdNi2O/JbrIOy,
	bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w,
	sam-uyr5N9Q2VtJg9hUCZPvPmw, cocci-/FJkirnvOdkvYVN+rsErww,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Benjamin Fair,
	linux-scsi-u79uwXL29TY76Z2rM5mHXA, Fabio Estevam,
	openbmc-uLR06cmDAlY/bJ5BZ2RsiQ, x86-DgEjT+Ai2ygdnm+yROfE0A,
	lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w, Nancy Yuen,
	mingo-H+wXaHxf7aLQT0dZR+AlfA, geert-Td1EMuHUCqxL1ZNQvxDV9g

On Wed, 21 Aug 2019, Matthias Maennich wrote:

> As of Linux 5.3-rc5, there are 31205 [1] exported symbols in the kernel.
> That is a growth of roughly 1000 symbols since 4.17 (30206 [2]).  There
> seems to be some consensus amongst kernel devs that the export surface
> is too large, and hard to reason about.

This is good work.

One solution for drastically reducing the effective export surface is to 
have CONFIG_TRIM_UNUSED_KSYMS=y. This is more extreme than symbol 
namespace, but might be worth mentioning nevertheless.


Nicolas

^ permalink raw reply	[flat|nested] 11+ messages in thread

[parent not found: <nycvar.YSQ.7.76.1908210840490.19480-fMhRO7WWcppj+hNMo8g0rg@public.gmane.org>]

* Re: [PATCH v3 00/11] Symbol Namespaces
       [not found]         ` <nycvar.YSQ.7.76.1908210840490.19480-fMhRO7WWcppj+hNMo8g0rg@public.gmane.org>
@ 2019-08-21 13:37           ` Greg KH
       [not found]             ` <20190821133737.GB4890-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
  0 siblings, 1 reply; 11+ messages in thread
From: Greg KH @ 2019-08-21 13:37 UTC (permalink / raw)
  To: Nicolas Pitre
  Cc: kstewart-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, oneukum-IBi9RG/b67k,
	linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	usb-storage-ijkIwGHArpdIPJnuZ7Njw4oP9KaGy4wf, Toru Komatsu,
	Mauro Carvalho Chehab, Nicolas Ferre, David Howells,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A, Will Deacon,
	patches-yzvPICuk2AA4QjBA90+/kJqQE7yCjDx5, Michael Ellerman,
	hpa-YMNOUZJC4hwAvxtiuMwx3w, joel-QYYGw3jwrUn5owFQY34kdNi2O/JbrIOy,
	bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w,
	sam-uyr5N9Q2VtJg9hUCZPvPmw, cocci-/FJkirnvOdkvYVN+rsErww,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Benjamin Fair,
	linux-scsi-u79uwXL29TY76Z2rM5mHXA, Fabio Estevam,
	openbmc-uLR06cmDAlY/bJ5BZ2RsiQ, x86-DgEjT+Ai2ygdnm+yROfE0A,
	lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w, Nancy Yuen,
	mingo-H+wXaHxf7aLQT0dZR+AlfA, geert-Td1EMuHUCqxL1ZNQvxDV9g,
	NXP Linux Team, Johan

On Wed, Aug 21, 2019 at 08:46:47AM -0400, Nicolas Pitre wrote:
> On Wed, 21 Aug 2019, Matthias Maennich wrote:
> 
> > As of Linux 5.3-rc5, there are 31205 [1] exported symbols in the kernel.
> > That is a growth of roughly 1000 symbols since 4.17 (30206 [2]).  There
> > seems to be some consensus amongst kernel devs that the export surface
> > is too large, and hard to reason about.
> 
> This is good work.
> 
> One solution for drastically reducing the effective export surface is to 
> have CONFIG_TRIM_UNUSED_KSYMS=y. This is more extreme than symbol 
> namespace, but might be worth mentioning nevertheless.

Oh that's amazing, I never noticed that feature.  That is a nice thing,
thanks for pointing it out.

greg k-h

^ permalink raw reply	[flat|nested] 11+ messages in thread

[parent not found: <20190821133737.GB4890-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>]

* Re: [PATCH v3 00/11] Symbol Namespaces
       [not found]             ` <20190821133737.GB4890-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
@ 2019-08-21 20:48               ` Nicolas Pitre
  0 siblings, 0 replies; 11+ messages in thread
From: Nicolas Pitre @ 2019-08-21 20:48 UTC (permalink / raw)
  To: Greg KH
  Cc: kstewart-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, oneukum-IBi9RG/b67k,
	linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	usb-storage-ijkIwGHArpdIPJnuZ7Njw4oP9KaGy4wf, Toru Komatsu,
	Mauro Carvalho Chehab, Nicolas Ferre, David Howells,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A, Will Deacon,
	patches-yzvPICuk2AA4QjBA90+/kJqQE7yCjDx5, Michael Ellerman,
	hpa-YMNOUZJC4hwAvxtiuMwx3w, joel-QYYGw3jwrUn5owFQY34kdNi2O/JbrIOy,
	bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w,
	sam-uyr5N9Q2VtJg9hUCZPvPmw, cocci-/FJkirnvOdkvYVN+rsErww,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Benjamin Fair,
	linux-scsi-u79uwXL29TY76Z2rM5mHXA, Fabio Estevam,
	openbmc-uLR06cmDAlY/bJ5BZ2RsiQ, x86-DgEjT+Ai2ygdnm+yROfE0A,
	lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w, Nancy Yuen,
	mingo-H+wXaHxf7aLQT0dZR+AlfA, geert-Td1EMuHUCqxL1ZNQvxDV9g,
	NXP Linux Team, Johan

On Wed, 21 Aug 2019, Greg KH wrote:

> On Wed, Aug 21, 2019 at 08:46:47AM -0400, Nicolas Pitre wrote:
> 
> > One solution for drastically reducing the effective export surface is to 
> > have CONFIG_TRIM_UNUSED_KSYMS=y. This is more extreme than symbol 
> > namespace, but might be worth mentioning nevertheless.
> 
> Oh that's amazing, I never noticed that feature.  That is a nice thing,
> thanks for pointing it out.

For those interested, this feature was demonstrated with numbers here:

https://lwn.net/Articles/746780/


Nicolas

^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 00/11] Symbol Namespaces
       [not found]     ` <20190821114955.12788-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
  2019-08-21 11:49       ` [PATCH v3 11/11] RFC: watchdog: export core symbols in WATCHDOG_CORE namespace Matthias Maennich
  2019-08-21 12:46       ` [PATCH v3 00/11] Symbol Namespaces Nicolas Pitre
@ 2019-08-21 13:11       ` Peter Zijlstra
       [not found]         ` <20190821131140.GC2349-Nxj+rRp3nVydTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
  2 siblings, 1 reply; 11+ messages in thread
From: Peter Zijlstra @ 2019-08-21 13:11 UTC (permalink / raw)
  To: Matthias Maennich
  Cc: kstewart-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, oneukum-IBi9RG/b67k,
	linux-stm32-XDFAJ8BFU24N7RejjzZ/Li2xQDfSxrLKVpNB7YpNyf8,
	linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	usb-storage-ijkIwGHArpdIPJnuZ7Njw4oP9KaGy4wf, Toru Komatsu,
	Mauro Carvalho Chehab, Nicolas Ferre, David Howells,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A, Will Deacon,
	patches-yzvPICuk2AA4QjBA90+/kJqQE7yCjDx5, Michael Ellerman,
	hpa-YMNOUZJC4hwAvxtiuMwx3w, joel-QYYGw3jwrUn5owFQY34kdNi2O/JbrIOy,
	bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w,
	sam-uyr5N9Q2VtJg9hUCZPvPmw, cocci-/FJkirnvOdkvYVN+rsErww,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Benjamin Fair,
	linux-scsi-u79uwXL29TY76Z2rM5mHXA, Fabio Estevam,
	openbmc-uLR06cmDAlY/bJ5BZ2RsiQ, x86-DgEjT+Ai2ygdnm+yROfE0A,
	lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w, Nancy Yuen,
	mingo-H+wXaHxf7aLQT0dZR+AlfA, geert-Td1EMuHUCqxL1ZNQvxDV9g

On Wed, Aug 21, 2019 at 12:49:15PM +0100, Matthias Maennich wrote:
> As of Linux 5.3-rc5, there are 31205 [1] exported symbols in the kernel.
> That is a growth of roughly 1000 symbols since 4.17 (30206 [2]).  There
> seems to be some consensus amongst kernel devs that the export surface
> is too large, and hard to reason about.
> 
> Generally, these symbols fall in one of these categories:
> 1) Symbols actually meant for drivers
> 2) Symbols that are only exported because functionality is split over
>    multiple modules, yet they really shouldn't be used by modules outside
>    of their own subsystem
> 3) Symbols really only meant for in-tree use
> 
> When module developers try to upstream their code, it regularly turns
> out that they are using exported symbols that they really shouldn't be
> using. This problem is even bigger for drivers that are currently
> out-of-tree, which may be using many symbols that they shouldn't be
> using, and that break when those symbols are removed or modified.
> 
> This patch allows subsystem maintainers to partition their exported
> symbols into separate namespaces, and module authors to import such
> namespaces only when needed.
> 
> This allows subsystem maintainers to more easily limit availability of
> these namespaced symbols to other parts of the kernel. It can also be
> used to partition the set of exported symbols for documentation
> purposes; for example, a set of symbols that is really only used for
> debugging could be in a "SUBSYSTEM_DEBUG" namespace.

I'm missing how one can prohibit these random out of tree modules from
doing MODULE_IMPORT_NS().

That is; suppose I stick all the preempt_notifier symbols in a KVM
namespace, how do I enforce no out-of-tree modules ever do
MODULE_IMPORT_NS(KVM) and gain access?

(the above would basically break virtualbox, which I knows uses preempt
notifiers too, but I don't give a rats arse about that)

^ permalink raw reply	[flat|nested] 11+ messages in thread

[parent not found: <20190821131140.GC2349-Nxj+rRp3nVydTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>]

* Re: [PATCH v3 00/11] Symbol Namespaces
       [not found]         ` <20190821131140.GC2349-Nxj+rRp3nVydTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
@ 2019-08-21 13:38           ` Greg KH
       [not found]             ` <20190821133846.GC4890-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
  0 siblings, 1 reply; 11+ messages in thread
From: Greg KH @ 2019-08-21 13:38 UTC (permalink / raw)
  To: Peter Zijlstra
  Cc: kstewart-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, oneukum-IBi9RG/b67k,
	linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ,
	usb-storage-ijkIwGHArpdIPJnuZ7Njw4oP9KaGy4wf, Toru Komatsu,
	Mauro Carvalho Chehab, Nicolas Ferre, David Howells,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A, Will Deacon,
	patches-yzvPICuk2AA4QjBA90+/kJqQE7yCjDx5, Michael Ellerman,
	hpa-YMNOUZJC4hwAvxtiuMwx3w, joel-QYYGw3jwrUn5owFQY34kdNi2O/JbrIOy,
	bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w,
	sam-uyr5N9Q2VtJg9hUCZPvPmw, cocci-/FJkirnvOdkvYVN+rsErww,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Benjamin Fair,
	linux-scsi-u79uwXL29TY76Z2rM5mHXA, Fabio Estevam,
	openbmc-uLR06cmDAlY/bJ5BZ2RsiQ, x86-DgEjT+Ai2ygdnm+yROfE0A,
	lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w, Nancy Yuen,
	mingo-H+wXaHxf7aLQT0dZR+AlfA, geert-Td1EMuHUCqxL1ZNQvxDV9g,
	NXP Linux Team, Johan

On Wed, Aug 21, 2019 at 03:11:40PM +0200, Peter Zijlstra wrote:
> On Wed, Aug 21, 2019 at 12:49:15PM +0100, Matthias Maennich wrote:
> > As of Linux 5.3-rc5, there are 31205 [1] exported symbols in the kernel.
> > That is a growth of roughly 1000 symbols since 4.17 (30206 [2]).  There
> > seems to be some consensus amongst kernel devs that the export surface
> > is too large, and hard to reason about.
> > 
> > Generally, these symbols fall in one of these categories:
> > 1) Symbols actually meant for drivers
> > 2) Symbols that are only exported because functionality is split over
> >    multiple modules, yet they really shouldn't be used by modules outside
> >    of their own subsystem
> > 3) Symbols really only meant for in-tree use
> > 
> > When module developers try to upstream their code, it regularly turns
> > out that they are using exported symbols that they really shouldn't be
> > using. This problem is even bigger for drivers that are currently
> > out-of-tree, which may be using many symbols that they shouldn't be
> > using, and that break when those symbols are removed or modified.
> > 
> > This patch allows subsystem maintainers to partition their exported
> > symbols into separate namespaces, and module authors to import such
> > namespaces only when needed.
> > 
> > This allows subsystem maintainers to more easily limit availability of
> > these namespaced symbols to other parts of the kernel. It can also be
> > used to partition the set of exported symbols for documentation
> > purposes; for example, a set of symbols that is really only used for
> > debugging could be in a "SUBSYSTEM_DEBUG" namespace.
> 
> I'm missing how one can prohibit these random out of tree modules from
> doing MODULE_IMPORT_NS().

Nothing, but then they are explicitly being "bad" :)

> That is; suppose I stick all the preempt_notifier symbols in a KVM
> namespace, how do I enforce no out-of-tree modules ever do
> MODULE_IMPORT_NS(KVM) and gain access?
> 
> (the above would basically break virtualbox, which I knows uses preempt
> notifiers too, but I don't give a rats arse about that)

It's a huge red flag for anyone reviewing the code that this module is
doing something it probably really should not be doing at all.  It will
make reviewing code easier, this isn't there to try to "prevent bad
actors" at all, sorry.

thanks,

greg k-h

^ permalink raw reply	[flat|nested] 11+ messages in thread

[parent not found: <20190821133846.GC4890-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>]

* Re: [PATCH v3 00/11] Symbol Namespaces
       [not found]             ` <20190821133846.GC4890-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
@ 2019-08-21 14:03               ` Matthias Maennich
  0 siblings, 0 replies; 11+ messages in thread
From: Matthias Maennich @ 2019-08-21 14:03 UTC (permalink / raw)
  To: Greg KH
  Cc: kstewart-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, oneukum-IBi9RG/b67k,
	linux-aspeed-uLR06cmDAlY/bJ5BZ2RsiQ, Peter Zijlstra, Toru Komatsu,
	Mauro Carvalho Chehab, Nicolas Ferre, David Howells,
	yamada.masahiro-uWyLwvC0a2jby3iVrkZq2A, Will Deacon,
	patches-yzvPICuk2AA4QjBA90+/kJqQE7yCjDx5, Michael Ellerman,
	hpa-YMNOUZJC4hwAvxtiuMwx3w, joel-QYYGw3jwrUn5owFQY34kdNi2O/JbrIOy,
	bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w,
	sam-uyr5N9Q2VtJg9hUCZPvPmw, cocci-/FJkirnvOdkvYVN+rsErww,
	linux-arch-u79uwXL29TY76Z2rM5mHXA,
	linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA, Benjamin Fair,
	linux-scsi-u79uwXL29TY76Z2rM5mHXA, Nancy Yuen, Fabio Estevam,
	openbmc-uLR06cmDAlY/bJ5BZ2RsiQ, x86-DgEjT+Ai2ygdnm+yROfE0A,
	lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w,
	usb-storage-ijkIwGHArpdIPJnuZ7Njw4oP9KaGy4wf,
	mingo-H+wXaHxf7aLQT0dZR+AlfA, geert-Td1EMuHUCqxL1ZNQvxDV9g, NX

On Wed, 21 Aug, 06:38, Greg Kroah-Hartman wrote:
>On Wed, Aug 21, 2019 at 03:11:40PM +0200, Peter Zijlstra wrote:
>> On Wed, Aug 21, 2019 at 12:49:15PM +0100, Matthias Maennich wrote:
>> > As of Linux 5.3-rc5, there are 31205 [1] exported symbols in the kernel.
>> > That is a growth of roughly 1000 symbols since 4.17 (30206 [2]).  There
>> > seems to be some consensus amongst kernel devs that the export surface
>> > is too large, and hard to reason about.
>> >
>> > Generally, these symbols fall in one of these categories:
>> > 1) Symbols actually meant for drivers
>> > 2) Symbols that are only exported because functionality is split over
>> >    multiple modules, yet they really shouldn't be used by modules outside
>> >    of their own subsystem
>> > 3) Symbols really only meant for in-tree use
>> >
>> > When module developers try to upstream their code, it regularly turns
>> > out that they are using exported symbols that they really shouldn't be
>> > using. This problem is even bigger for drivers that are currently
>> > out-of-tree, which may be using many symbols that they shouldn't be
>> > using, and that break when those symbols are removed or modified.
>> >
>> > This patch allows subsystem maintainers to partition their exported
>> > symbols into separate namespaces, and module authors to import such
>> > namespaces only when needed.
>> >
>> > This allows subsystem maintainers to more easily limit availability of
>> > these namespaced symbols to other parts of the kernel. It can also be
>> > used to partition the set of exported symbols for documentation
>> > purposes; for example, a set of symbols that is really only used for
>> > debugging could be in a "SUBSYSTEM_DEBUG" namespace.
>>
>> I'm missing how one can prohibit these random out of tree modules from
>> doing MODULE_IMPORT_NS().
>
>Nothing, but then they are explicitly being "bad" :)
>

As a side effect of this implementation (namespace imports via modinfo
tags), imports are very visible for (out-of-tree) modules, e.g.

$ modinfo drivers/usb/storage/ums-usbat.ko
  filename:       drivers/usb/storage/ums-usbat.ko
  import_ns:      USB_STORAGE
  license:        GPL
  author:         ...
  ...

>> That is; suppose I stick all the preempt_notifier symbols in a KVM
>> namespace, how do I enforce no out-of-tree modules ever do
>> MODULE_IMPORT_NS(KVM) and gain access?
>>

That is actually a feature worth following up: Restricting the
namespaces that can be imported by modules. I am afraid it is not part
of this series, but should not be too hard once agreed how such a list
will be defined.

>> (the above would basically break virtualbox, which I knows uses preempt
>> notifiers too, but I don't give a rats arse about that)
>
>It's a huge red flag for anyone reviewing the code that this module is
>doing something it probably really should not be doing at all.  It will
>make reviewing code easier, this isn't there to try to "prevent bad
>actors" at all, sorry.
>

Cheers,
Matthias

^ permalink raw reply	[flat|nested] 11+ messages in thread

end of thread, other threads:[~2019-08-21 20:48 UTC | newest]

Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
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     [not found] ` <20190813121733.52480-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2019-08-21 11:49   ` [PATCH v3 00/11] Symbol Namespaces Matthias Maennich
     [not found]     ` <20190821114955.12788-1-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2019-08-21 11:49       ` [PATCH v3 11/11] RFC: watchdog: export core symbols in WATCHDOG_CORE namespace Matthias Maennich
     [not found]         ` <20190821114955.12788-12-maennich-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2019-08-21 12:39           ` Greg KH
2019-08-21 14:59           ` Guenter Roeck
     [not found]             ` <20190821145911.GA6521-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org>
2019-08-21 16:28               ` Matthias Maennich
2019-08-21 12:46       ` [PATCH v3 00/11] Symbol Namespaces Nicolas Pitre
     [not found]         ` <nycvar.YSQ.7.76.1908210840490.19480-fMhRO7WWcppj+hNMo8g0rg@public.gmane.org>
2019-08-21 13:37           ` Greg KH
     [not found]             ` <20190821133737.GB4890-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
2019-08-21 20:48               ` Nicolas Pitre
2019-08-21 13:11       ` Peter Zijlstra
     [not found]         ` <20190821131140.GC2349-Nxj+rRp3nVydTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2019-08-21 13:38           ` Greg KH
     [not found]             ` <20190821133846.GC4890-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
2019-08-21 14:03               ` Matthias Maennich

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