When the kernel is running in secure boot mode, we lock down the kernel to
prevent userspace from modifying the running kernel image. Whilst this
includes prohibiting access to things like /dev/mem, it must also prevent
access by means of configuring driver modules in such a way as to cause a
device to access or modify the kernel image.
To this end, annotate module_param* statements that refer to hardware
configuration and indicate for future reference what type of parameter they
specify. The parameter parser in the core sees this information and can
skip such parameters with an error message if the kernel is locked down.
The module initialisation then runs as normal, but just sees whatever the
default values for those parameters is.
Note that we do still need to do the module initialisation because some
drivers have viable defaults set in case parameters aren't specified and
some drivers support automatic configuration (e.g. PNP or PCI) in addition
to manually coded parameters.
This patch annotates drivers in drivers/watchdog/.
Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
cc: Wim Van Sebroeck <wim@iguana.be>
cc: Zwane Mwaikambo <zwanem@gmail.com>
cc: linux-watchdog@vger.kernel.org
If loaded with isapnp = 0 the driver explodes. This is catching
people out now and then. What should happen in the working case is
a complete mystery and the code appears terminally confused, but we
can at least make the error path work properly.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Partially-Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=53991
I just can't find any value in MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR)
and MODULE_ALIAS_MISCDEV(TEMP_MINOR) statements.
Either the device is enumerated and the driver already has a module
alias (e.g. PCI, USB etc.) that will get the right driver loaded
automatically.
Or the device is not enumerated and loading its driver will lead to
more or less intrusive hardware poking. Such hardware poking should be
limited to a bare minimum, so the user should really decide which
drivers should be tried and in what order. Trying them all in
arbitrary order can't do any good.
On top of that, loading that many drivers at once bloats the kernel
log. Also many drivers will stay loaded afterward, bloating the output
of "lsmod" and wasting memory. Some modules (cs5535_mfgpt which gets
loaded as a dependency) can't even be unloaded!
If defining char-major-10-130 is needed then it should happen in
user-space.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Cc: Jim Cromie <jim.cromie@gmail.com>
Use the current logging styles.
Make sure all output has a prefix.
Add missing newlines.
Remove now unnecessary PFX, NAME, and miscellaneous other #defines.
Coalesce formats.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This brings the watchdog drivers into line with coding style.
This patch takes cares of the indentation as described in chapter 1.
Main changes:
* Re-structure the ioctl switch call for all drivers as follows:
switch (cmd) {
case WDIOC_GETSUPPORT:
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
case WDIOC_GETTEMP:
case WDIOC_SETOPTIONS:
case WDIOC_KEEPALIVE:
case WDIOC_SETTIMEOUT:
case WDIOC_GETTIMEOUT:
case WDIOC_GETTIMELEFT:
default:
}
This to make the migration from the drivers to the uniform watchdog
device driver easier in the future.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This brings the watchdog drivers into line with coding style.
This patch takes cares of the indentation as described in chapter 1:
The preferred way to ease multiple indentation levels in a switch
statement is to align the "switch" and its subordinate "case"
labels in the same column instead of "double-indenting" the "case"
labels.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Some watchdog drivers initialize global spinlocks in module's init function
which is tolerable, but some do it in PCI probe function. So, switch to
static initialization to fix theoretical bugs and, more importantly, stop
giving people bad examples.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
David Howells