Re: [PATCH] nvme-pci: add NVME_QUIRK_NO_SECONDARY_TEMP_THRESH for WD SN740

[Guenter Roeck <linux@roeck-us.net>]

On 11/2/26 23:58, Christoph Hellwig wrote:
> On Fri, Oct 30, 2026 at 12:05:13AM -0300, Robson Cassiano wrote:
>> The WD SN740 (15b7:5017) reports two secondary temperature sensors in
>> the SMART/Health log but returns the 0 and 0xffff (Kelvin) sentinels
>> for their temperature thresholds. nvme-hwmon exposes those as
>> temp2_min/max and temp3_min/max, producing -273.15 C and 65261.85 C in
>> sysfs.
>>
>> Mark the controller with NVME_QUIRK_NO_SECONDARY_TEMP_THRESH so only
>> the sensor inputs are exposed.
> 
> Given that this is an older device I suspect we're not going to
> see firmware fixes for it.  But given that we had quite a few devices
> with issues like this, I wonder why nvme-hwmon can't detect these
> obviously fake values instead and we could drop the quirk?
> 

Question is if the quirk is really needed. Personally I doubt it.
Normally the thresholds are simply not set. I see that with the NVMEs
on my system (Samsung SSD 990 PRO) as well. If I set min and max
values, they are stored and subsequently displayed correctly.
That means, no, the hwmon driver can _not_ detect if those values
are fake because it can not distinguish "not set" from "not really
supported".

I have not seen the patch, but I strongly suspect that it fixes
a non-issue, unless it can be shown that writing the values has no
effect.

Guenter