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Subject: Re: [PATCH] watchdog: iTCO_wdt: Fix detection of SMI-off case
From:   Jan Kiszka <jan.kiszka@siemens.com>
To:     Wim Van Sebroeck <wim@linux-watchdog.org>,
        Guenter Roeck <linux@roeck-us.net>
Cc:     linux-watchdog@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Christian Storm <christian.storm@siemens.com>,
        Andy Shevchenko <andy.shevchenko@gmail.com>,
        =?UTF-8?Q?Mantas_Mikul=c4=97nas?= <grawity@gmail.com>
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Message-ID: <1444efd5-b778-949b-34e8-99d2541350e9@siemens.com>
Date:   Fri, 20 Aug 2021 15:45:06 +0200
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On 26.07.21 13:46, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@siemens.com>
> 
> Obviously, the test needs to run against the register content, not its
> address.
> 
> Fixes: cb011044e34c ("watchdog: iTCO_wdt: Account for rebooting on second timeout")
> Reported-by: Mantas Mikulėnas <grawity@gmail.com>
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>  drivers/watchdog/iTCO_wdt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
> index b3f604669e2c..643c6c2d0b72 100644
> --- a/drivers/watchdog/iTCO_wdt.c
> +++ b/drivers/watchdog/iTCO_wdt.c
> @@ -362,7 +362,7 @@ static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
>  	 * Otherwise, the BIOS generally reboots when the SMI triggers.
>  	 */
>  	if (p->smi_res &&
> -	    (SMI_EN(p) & (TCO_EN | GBL_SMI_EN)) != (TCO_EN | GBL_SMI_EN))
> +	    (inl(SMI_EN(p)) & (TCO_EN | GBL_SMI_EN)) != (TCO_EN | GBL_SMI_EN))
>  		tmrval /= 2;
>  
>  	/* from the specs: */
> 

Ping, this is still missing in master. Stable kernels had the revert,
but 5.14 will need this.

Jan

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