If a driver's watchdog_device struct is part of a dynamically allocated
struct (which it often will be), merely locking the module is not enough,
even with a drivers module locked, the driver can be unbound from the device,
examples:
1) The root user can unbind it through sysfd
2) The i2c bus master driver being unloaded for an i2c watchdog
I will gladly admit that these are corner cases, but we still need to handle
them correctly.
The fix for this consists of 2 parts:
1) Add ref / unref operations, so that the driver can refcount the struct
holding the watchdog_device struct and delay freeing it until any
open filehandles referring to it are closed
2) Most driver operations will do IO on the device and the driver should not
do any IO on the device after it has been unbound. Rather then letting each
driver deal with this internally, it is better to ensure at the watchdog
core level that no operations (other then unref) will get called after
the driver has called watchdog_unregister_device(). This actually is the
bulk of this patch.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This patch fixes some potential multithreading issues, despite only
allowing one process to open the /dev/watchdog device, we can still get
called multiple times at the same time, since a program could be using thread,
or could share the fd after a fork.
This causes 2 potential problems:
1) watchdog_start / open do an unlocked test_n_set / test_n_clear,
if these 2 race, the watchdog could be stopped while the active
bit indicates it is running or visa versa.
2) Most watchdog_dev drivers probably assume that only one
watchdog-op will get called at a time, this is not necessary
true atm.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Rewrite and extend the wrapper code so that we can easily introduce
locking (this to be able to prevent potential multithreading issues).
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
While they are registered all our watchdogs now have a valid device object
so we can in turn use that to report problems nicely.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Some watchdogs merely trigger external alarms and controls. In a managed
environment this is very useful but we want drivers to be able to figure
out which is which now multiple dogs can be loaded. Thus add an ALARMONLY
feature flag.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
We keep the old /dev/watchdog interface file for the first watchdog via
miscdev. This is basically a cut and paste of the relevant interface code
from the rtc driver layer tweaked for watchdog.
Revised to fix problems noted by Hans de Goede
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
The watchdog_core include file should have been named
watchdog_core.h and not watchdog_dev.h . Correct this.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Some watchdog may need to check if watchdog is ACTIVE or not, for example in
their suspend/resume hooks.
This patch adds this routine and changes the core drivers to use it.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Include the private watchdog_dev.h header to pickup the prototypes for the
watchdog_dev_register/unregister functions.
This quiets the following sparse warnings:
warning: symbol 'watchdog_dev_register' was not declared. Should it be static?
warning: symbol 'watchdog_dev_unregister' was not declared. Should it be static?
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Pull x86 trampoline rework from H. Peter Anvin:
"This code reworks all the "trampoline"/"realmode" code (various bits
that need to live in the first megabyte of memory, most but not all of
which runs in real mode at some point) in the kernel into a single
object. The main reason for doing this is that it eliminates the last
place in the kernel where we needed pages to be mapped RWX. This code
separates all that code into proper R/RW/RX pages."
Fix up conflicts in arch/x86/kernel/Makefile (mca removed next to reboot
code), and arch/x86/kernel/reboot.c (reboot code moved around in one
branch, modified in this one), and arch/x86/tools/relocs.c (mostly same
code came in earlier due to working around the ld bugs just before the
3.4 release).
Also remove stale x86-relocs entry from scripts/.gitignore as per Peter
Anvin.
* commit '61f5446169046c217a5479517edac3a890c3bee7': (36 commits)
x86, realmode: Move end signature into header.S
x86, relocs: When printing an error, say relative or absolute
x86, relocs: More relocations which may end up as absolute
x86, relocs: Workaround for binutils 2.22.52.0.1 section bug
xen-acpi-processor: Add missing #include <xen/xen.h>
acpi, bgrd: Add missing <linux/io.h> to drivers/acpi/bgrt.c
x86, realmode: Change EFER to a single u64 field
x86, realmode: Move kernel/realmode.c to realmode/init.c
x86, realmode: Move not-common bits out of trampoline_common.S
x86, realmode: Mask out EFER.LMA when saving trampoline EFER
x86, realmode: Fix no cache bits test in reboot_32.S
x86, realmode: Make sure all generated files are listed in targets
x86, realmode: build fix: remove duplicate build
x86, realmode: read cr4 and EFER from kernel for 64-bit trampoline
x86, realmode: fixes compilation issue in tboot.c
x86, realmode: move relocs from scripts/ to arch/x86/tools
x86, realmode: header for trampoline code
x86, realmode: flattened rm hierachy
x86, realmode: don't copy real_mode_header
x86, realmode: fix 64-bit wakeup sequence
...
Pull EDAC internal API changes from Mauro Carvalho Chehab:
"This changeset is the first part of a series of patches that fixes the
EDAC sybsystem. On this set, it changes the Kernel EDAC API in order
to properly represent the Intel i3/i5/i7, Xeon 3xxx/5xxx/7xxx, and
Intel E5-xxxx memory controllers.
The EDAC core used to assume that:
- the DRAM chip select pin is directly accessed by the memory
controller
- when multiple channels are used, they're all filled with the
same type of memory.
None of the above premises is true on Intel memory controllers since
2002, when RAMBUS and FB-DIMMs were introduced, and Advanced Memory
Buffer or by some similar technologies hides the direct access to the
DRAM pins.
So, the existing drivers for those chipsets had to lie to the EDAC
core, in general telling that just one channel is filled. That
produces some hard to understand error messages like:
EDAC MC0: CE row 3, channel 0, label "DIMM1": 1 Unknown error(s): memory read error on FATAL area : cpu=0 Err=0008:00c2 (ch=2), addr = 0xad1f73480 => socket=0, Channel=0(mask=2), rank=1
The location information there (row3 channel 0) is completely bogus:
it has no physical meaning, and are just some random values that the
driver uses to talk with the EDAC core. The error actually happened
at CPU socket 0, channel 0, slot 1, but this is not reported anywhere,
as the EDAC core doesn't know anything about the memory layout. So,
only advanced users that know how the EDAC driver works and that tests
their systems to see how DIMMs are mapped can actually benefit for
such error logs.
This patch series fixes the error report logic, in order to allow the
EDAC to expose the memory architecture used by them to the EDAC core.
So, as the EDAC core now understands how the memory is organized, it
can provide an useful report:
EDAC MC0: CE memory read error on DIMM1 (channel:0 slot:1 page:0x364b1b offset:0x600 grain:32 syndrome:0x0 - count:1 area:DRAM err_code:0001:0090 socket:0 channel_mask:1 rank:4)
The location of the DIMM where the error happened is reported by "MC0"
(cpu socket #0), at "channel:0 slot:1" location, and matches the
physical location of the DIMM.
There are two remaining issues not covered by this patch series:
- The EDAC sysfs API will still report bogus values. So,
userspace tools like edac-utils will still use the bogus data;
- Add a new tracepoint-based way to get the binary information
about the errors.
Those are on a second series of patches (also at -next), but will
probably miss the train for 3.5, due to the slow review process."
Fix up trivial conflict (due to spelling correction of removed code) in
drivers/edac/edac_device.c
* git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac: (42 commits)
i7core: fix ranks information at the per-channel struct
i5000: Fix the fatal error handling
i5100_edac: Fix a warning when compiled with 32 bits
i82975x_edac: Test nr_pages earlier to save a few CPU cycles
e752x_edac: provide more info about how DIMMS/ranks are mapped
i5000_edac: Fix the logic that retrieves memory information
i5400_edac: improve debug messages to better represent the filled memory
edac: Cleanup the logs for i7core and sb edac drivers
edac: Initialize the dimm label with the known information
edac: Remove the legacy EDAC ABI
x38_edac: convert driver to use the new edac ABI
tile_edac: convert driver to use the new edac ABI
sb_edac: convert driver to use the new edac ABI
r82600_edac: convert driver to use the new edac ABI
ppc4xx_edac: convert driver to use the new edac ABI
pasemi_edac: convert driver to use the new edac ABI
mv64x60_edac: convert driver to use the new edac ABI
mpc85xx_edac: convert driver to use the new edac ABI
i82975x_edac: convert driver to use the new edac ABI
i82875p_edac: convert driver to use the new edac ABI
...
Pull MIPS updates from Ralf Baechle:
"The whole series has been sitting in -next for quite a while with no
complaints. The last change to the series was before the weekend the
removal of an SPI patch which Grant - even though previously acked by
himself - appeared to raise objections. So I removed it until the
situation is clarified. Other than that all the patches have the acks
from their respective maintainers, all MIPS and x86 defconfigs are
building fine and I'm not aware of any problems introduced by this
series.
Among the key features for this patch series is a sizable patchset for
Lantiq which among other things introduces support for Lantiq's
flagship product, the FALCON SOC. It also means that the opensource
developers behind this patchset have overtaken Lantiq's competing
inhouse development team that was working behind closed doors.
Less noteworthy the ath79 patchset which adds support for a few more
chip variants, cleanups and fixes. Finally the usual dose of tweaking
of generic code."
Fix up trivial conflicts in arch/mips/lantiq/xway/gpio_{ebu,stp}.c where
printk spelling fixes clashed with file move and eventual removal of the
printk.
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (81 commits)
MIPS: lantiq: remove orphaned code
MIPS: Remove all -Wall and almost all -Werror usage from arch/mips.
MIPS: lantiq: implement support for FALCON soc
MTD: MIPS: lantiq: verify that the NOR interface is available on falcon soc
MTD: MIPS: lantiq: implement OF support
watchdog: MIPS: lantiq: implement OF support and minor fixes
SERIAL: MIPS: lantiq: implement OF support
GPIO: MIPS: lantiq: convert gpio-stp-xway to OF
GPIO: MIPS: lantiq: convert gpio-mm-lantiq to OF and of_mm_gpio
GPIO: MIPS: lantiq: move gpio-stp and gpio-ebu to the subsystem folder
MIPS: pci: convert lantiq driver to OF
MIPS: lantiq: convert dma to platform driver
MIPS: lantiq: implement support for clkdev api
MIPS: lantiq: drop ltq_gpio_request() and gpio_to_irq()
OF: MIPS: lantiq: implement irq_domain support
OF: MIPS: lantiq: implement OF support
MIPS: lantiq: drop mips_machine support
OF: PCI: const usage needed by MIPS
MIPS: Cavium: Remove smp_reserve_lock.
MIPS: Move cache setup to setup_arch().
...
Pull arm updates from Russell King:
"This contains both some fixes found when trying to get the
Assabet+neponset setup as a replacement firewall with a 3c589 PCMCIA
card, and a bunch of changes from Al to fix up the ARM signal
handling, particularly some of the restart behaviour."
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm:
ARM: neponset: make sure neponset_ncr_frob() is exported
ARM: fix out[bwl]()
arm: don't open-code ptrace_report_syscall()
arm: bury unused _TIF_RESTORE_SIGMASK
arm: remove unused restart trampoline
arm: new way of handling ERESTART_RESTARTBLOCK
arm: if we get into work_pending while returning to kernel mode, just go away
arm: don't call try_to_freeze() from do_signal()
arm: if there's no handler we need to restore sigmask, syscall or no syscall
arm: trim _TIF_WORK_MASK, get rid of useless test and branch...
arm: missing checks of __get_user()/__put_user() return values
Merge patches through Andrew Morton:
"180 patches - err 181 - listed below:
- most of MM. I held back the (large) "memcg: add hugetlb extension"
series because a bunfight has recently broken out.
- leds. After this, Bryan Wu will be handling drivers/leds/
- backlight
- lib/
- rtc"
* emailed from Andrew Morton <akpm@linux-foundation.org>: (181 patches)
drivers/rtc/rtc-s3c.c: fix compiler warning
drivers/rtc/rtc-tegra.c: clean up probe/remove routines
drivers/rtc/rtc-pl031.c: remove RTC timer interrupt handling
drivers/rtc/rtc-lpc32xx.c: add device tree support
drivers/rtc/rtc-m41t93.c: don't let get_time() reset M41T93_FLAG_OF
rtc: ds1307: add trickle charger support
rtc: ds1307: remove superfluous initialization
rtc: rename CONFIG_RTC_MXC to CONFIG_RTC_DRV_MXC
drivers/rtc/Kconfig: place RTC_DRV_IMXDI and RTC_MXC under "on-CPU RTC drivers"
drivers/rtc/rtc-pcf8563.c: add RTC_VL_READ/RTC_VL_CLR ioctl feature
rtc: add ioctl to get/clear battery low voltage status
drivers/rtc/rtc-ep93xx.c: convert to use module_platform_driver()
rtc/spear: add Device Tree probing capability
lib/vsprintf.c: "%#o",0 becomes '0' instead of '00'
radix-tree: fix preload vector size
spinlock_debug: print kallsyms name for lock
vsprintf: fix %ps on non symbols when using kallsyms
lib/bitmap.c: fix documentation for scnprintf() functions
lib/string_helpers.c: make arrays static
lib/test-kstrtox.c: mark const init data with __initconst instead of __initdata
...
Use the devres managed resource functions in the probe routine. Also
affects the remove routine where the previously used free and release
functions are not needed.
The devm_* functions eliminate the need for manual resource releasing and
simplify error handling. Resources allocated by devm_* are freed
automatically on driver detach.
Signed-off-by: Hannu Heikkinen <ext-hannu.m.heikkinen@nokia.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hans de Goede
Alan Cox
Wim Van Sebroeck
Viresh Kumar
H Hartley Sweeten
Linus Torvalds
Arnaldo Carvalho de Melo
Sachin Kamat
Hannu Heikkinen
Rajkumar Kasirajan
Roland Stigge