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From: "Pádraig Brady" <P@draigBrady.com>
To: Simon Kagstrom <simon.kagstrom@netinsight.net>
Cc: linux-kernel@vger.kernel.org, wim@iguana.be, seth.heasley@intel.com
Subject: Re: [PATCH] iTCO_wdt: Don't stop on shutdown with nowayout
Date: Tue, 23 Feb 2010 16:24:52 +0000	[thread overview]
Message-ID: <4B840154.1010501@draigBrady.com> (raw)
In-Reply-To: <20100223164019.60a6de1a@marrow.netinsight.se>

On 23/02/10 15:40, Simon Kagstrom wrote:
> Currently, the watchdog is turned off when the system shuts down or the
> module is unloaded. If nowayout has been selected, this makes no sense
> and fails to restart the system if it hangs during reboot, so make it
> conditional.
>
> Signed-off-by: Simon Kagstrom<simon.kagstrom@netinsight.net>
> ---
> We have a system which has such a hang, and therefore want the watchdog
> to be on until the bitter end.
>
>   drivers/watchdog/iTCO_wdt.c |    3 ++-
>   1 files changed, 2 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
> index 4bdb7f1..927df26 100644
> --- a/drivers/watchdog/iTCO_wdt.c
> +++ b/drivers/watchdog/iTCO_wdt.c
> @@ -839,7 +839,8 @@ static int __devexit iTCO_wdt_remove(struct platform_device *dev)
>
>   static void iTCO_wdt_shutdown(struct platform_device *dev)
>   {
> -	iTCO_wdt_stop();
> +	if (!nowayout)
> +		iTCO_wdt_stop();
>   }
>
>   #define iTCO_wdt_suspend NULL

I see the issue, however what happens if you're
rebooting into a system that doesn't then renable the watchdog.
I've seen systems where the hardware watchdog is not reset
during the reboot process, in which case you'll get a
reboot while running the other system.

If you had a readonly system, then perhaps you
can just  WDIOC_SETTIMEOUT the hardware watchdog timeout to 1s
and wait for it to reboot the system?

cheers,
Pádraig.

  reply	other threads:[~2010-02-23 16:29 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-02-23 15:40 [PATCH] iTCO_wdt: Don't stop on shutdown with nowayout Simon Kagstrom
2010-02-23 16:24 ` Pádraig Brady [this message]
2010-02-23 17:09   ` [PATCH] iTCO_wdt: Don't double the requested timeout Pádraig Brady
2010-02-24  9:16     ` Simon Kagstrom
2010-02-24 16:18       ` Pádraig Brady
2010-04-07 16:20         ` Pádraig Brady
     [not found]       ` <4B84FD15.9020803@draigBrady.com>
     [not found]         ` <20100224124730.6958b2c0@marrow.netinsight.se>
     [not found]           ` <4B8545D1.8000302@draigBrady.com>
     [not found]             ` <20100224165526.61cdd169@marrow.netinsight.se>
     [not found]               ` <4B854F58.4050907@draigBrady.com>
2010-02-25  7:45                 ` Simon Kagstrom
2010-02-24  6:25   ` [PATCH] iTCO_wdt: Don't stop on shutdown with nowayout Simon Kagstrom
2010-03-07 15:16 ` Wim Van Sebroeck
2010-03-08  7:51   ` Simon Kagstrom

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