linux-stable.git/drivers/watchdog, branch linux-3.10.y

watchdog: rc32434_wdt: fix ioctl error handling

2016-06-07T08:42:46+00:00

commit 10e7ac22cdd4d211cef99afcb9371b70cb175be6 upstream.

Calling return copy_to_user(...) in an ioctl will not do the right thing
if there's a pagefault: copy_to_user returns the number of bytes not
copied in this case.

Fix up watchdog/rc32434_wdt to do
	return copy_to_user(...)) ?  -EFAULT : 0;

instead.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck 
Signed-off-by: Willy Tarreau

watchdog: omap: assert the counter being stopped before reprogramming

2015-08-03T16:29:47+00:00

commit 530c11d432727c697629ad5f9d00ee8e2864d453 upstream.

The omap watchdog has the annoying behaviour that writes to most
registers don't have any effect when the watchdog is already running.
Quoting the AM335x reference manual:

	To modify the timer counter value (the WDT_WCRR register),
	prescaler ratio (the WDT_WCLR[4:2] PTV bit field), delay
	configuration value (the WDT_WDLY[31:0] DLY_VALUE bit field), or
	the load value (the WDT_WLDR[31:0] TIMER_LOAD bit field), the
	watchdog timer must be disabled by using the start/stop sequence
	(the WDT_WSPR register).

Currently the timer is stopped in the .probe callback but still there
are possibilities that yield to a situation where omap_wdt_start is
entered with the timer running (e.g. when /dev/watchdog is closed
without stopping and then reopened). In such a case programming the
timeout silently fails!

To circumvent this stop the timer before reprogramming.

Assuming one of the first things the watchdog user does is setting the
timeout explicitly nothing too bad should happen because this explicit
setting works fine.

Fixes: 7768a13c252a ("[PATCH] OMAP: Add Watchdog driver support")
Signed-off-by: Uwe Kleine-König 
Reviewed-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck 
Signed-off-by: Greg Kroah-Hartman

watchdog: ath79_wdt: avoid spurious restarts on AR934x

2014-07-07T01:54:14+00:00

commit 23afeb613ec0e10aecfae7838a14d485db62ac52 upstream.

On some AR934x based systems, where the frequency of
the AHB bus is relatively high, the built-in watchdog
causes a spurious restart when it gets enabled.

The possible cause of these restarts is that the timeout
value written into the TIMER register does not reaches
the hardware in time.

Add an explicit delay into the ath79_wdt_enable function
to avoid the spurious restarts.

Signed-off-by: Gabor Juhos 
Reviewed-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck 
Signed-off-by: Greg Kroah-Hartman

watchdog: sp805: Set watchdog_device->timeout from ->set_timeout()

2014-07-07T01:54:14+00:00

commit 938626d96a3ffb9eb54552bb0d3a4f2b30ffdeb0 upstream.

Implementation of ->set_timeout() is supposed to set 'timeout' field of 'struct
watchdog_device' passed to it. sp805 was rather setting this in a local
variable. Fix it.

Reported-by: Arun Ramamurthy 
Signed-off-by: Viresh Kumar 
Reviewed-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck 
Signed-off-by: Greg Kroah-Hartman

sc1200_wdt: Fix oops

2013-12-20T15:45:11+00:00

commit dace8bbfccfd9e4fcccfffcfbd82881fda3e756f upstream.

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 
Reviewed-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck 
Partially-Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=53991
Signed-off-by: Greg Kroah-Hartman

watchdog: ts72xx_wdt: locking bug in ioctl

2013-10-18T14:45:45+00:00

commit 8612ed0d97abcf1c016d34755b7cf2060de71963 upstream.

Calling the WDIOC_GETSTATUS & WDIOC_GETBOOTSTATUS and twice will cause a
interruptible deadlock.

Signed-off-by: Dan Carpenter 
Reviewed-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck 
Cc: Jonghwan Choi 
Signed-off-by: Greg Kroah-Hartman

drivers/watchdog: don't check resource with devm_ioremap_resource

2013-05-18T09:58:04+00:00

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.

Signed-off-by: Wolfram Sang

watchdog: Fix race condition in registration code

2013-05-09T06:13:41+00:00

A race condition exists when registering the first watchdog device.
Sequence of events:

- watchdog_register_device calls watchdog_dev_register
- watchdog_dev_register creates the watchdog misc device by calling
  misc_register.
  At that time, the matching character device (/dev/watchdog0) does not yet
  exist, and old_wdd is not set either.
- Userspace gets an event and opens /dev/watchdog
- watchdog_open is called and sets wdd = old_wdd, which is still NULL,
  and tries to dereference it. This causes the kernel to panic.

Seen with systemd trying to open /dev/watchdog immediately after
it was created.

Reported-by: Arkadiusz Miskiewicz 
Signed-off-by: Guenter Roeck 
Tested-by: Arkadiusz Miskiewicz 
Signed-off-by: Wim Van Sebroeck

watchdog: Convert to devm_ioremap_resource()

2013-05-09T06:12:00+00:00

Use the newly introduced devm_ioremap_resource() instead of
devm_request_and_ioremap() which provides more consistent error handling.

devm_ioremap_resource() provides its own error messages; so all explicit
error messages can be removed from the failure code paths.

Signed-off-by: Sachin Kamat 
Reviewed-by: Thierry Reding 
Cc: Gabor Juhos 
Cc: Paul Mundt 
Signed-off-by: Wim Van Sebroeck

watchdog: Revert the AT91RM9200_WATCHDOG dependency

2013-04-14T07:09:10+00:00

Compiling the at91rm9200_wdt.c driver without at91rm9200
support was leading to several errors:

drivers/built-in.o: In function `at91_wdt_close':
at91_adc.c:(.text+0xc9fe4): undefined reference to `at91_st_base'
drivers/built-in.o: In function `at91_wdt_write':
at91_adc.c:(.text+0xca004): undefined reference to `at91_st_base'
drivers/built-in.o: In function `at91wdt_shutdown':
at91_adc.c:(.text+0xca01c): undefined reference to `at91_st_base'
drivers/built-in.o: In function `at91wdt_suspend':
at91_adc.c:(.text+0xca038): undefined reference to `at91_st_base'
drivers/built-in.o: In function `at91_wdt_open':
at91_adc.c:(.text+0xca0cc): undefined reference to `at91_st_base'
drivers/built-in.o:at91_adc.c:(.text+0xca2c8): more undefined references to
`at91_st_base' follow

So, reverting the modification of the "depends" Kconfig line
introduced by patch a6a1bcd37 (watchdog: at91rm9200: add DT support)
seems to be the good solution.

Signed-off-by: Nicolas Ferre 
Acked-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck