On Fri, Feb 24, 2017 at 07:37:53AM -0800, Guenter Roeck wrote:

On 02/24/2017 07:11 AM, Krzysztof Kozlowski wrote:

quoted

In soft (no-reboot) mode, the driver self-pings watchdog upon expiration
of an interrupt.  However the interrupt itself was not cleared thus on
first hit, the system enters infinite interrupt handling loop.

On Odroid U3 (Exynos4412), when booted with s3c2410_wdt.soft_noboot=1
argument the console is flooded:
	# killall -9 watchdog
	[   60.523760] s3c2410-wdt 10060000.watchdog: watchdog timer expired (irq)
	[   60.536744] s3c2410-wdt 10060000.watchdog: watchdog timer expired (irq)

Fix this by writing something to the WTCLRINT register to clear the
interrupt.  The register WTCLRINT however appeared in S3C6410 so a new
watchdog quirk and flavor are needed.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

quoted

---

I was thinking about CC-ing stable, especially when I thought about
adding unconditional WTCLRINT clear.  However it appears that S3C2410
does not have the WTCLRINT register, this a new chip flavor has to be
added.  This makes the fix spread over driver and DTS changes.

Worth adding:
	Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
?

How would that be different to Cc: stable ?

I guess not much... except for the metrics that some bug was fixed.

Best regards,
Krzysztof