Re: [PATCH] watchdog: iTCO_wdt: Fix detection of SMI-off case

From: Jan Kiszka
Date: Mon Jul 26 2021 - 08:06:01 EST


On 26.07.21 14:03, Paolo Bonzini wrote:
> On 26/07/21 13:46, Jan Kiszka wrote:
>> From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
>>
>> 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@xxxxxxxxx>
>> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
>> ---
>>   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: */
>>
>
> Reviewed-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
>
> (the latter because cb011044e34c has been picked up by stable kernels
> already).
>

Thanks. Originally wanted to add stable myself, but I'm still unsure
whether this is the privilege of the subsystem maintainer or should also
be done by contributors.

Jan

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