Re: [PATCH] Watchdog: sp5100_tco: Lower verbosity of disabled watchdog hardware

From: Guenter Roeck
Date: Mon May 09 2022 - 21:15:48 EST


On 5/9/22 17:37, Mario Limonciello wrote:
On 5/9/22 19:33, Jerry Hoemann wrote:
On Mon, May 09, 2022 at 03:55:54PM -0700, Guenter Roeck wrote:
On 5/9/22 09:33, Mario Limonciello wrote:
If watchdog hardware has been disabled, currently the kernel driver
will show at err level during probe:

"Watchdog hardware is disabled"

This is unnecessarily verbose as there is already a -ENODEV returned.
Lower the level to debug.

Is it ? Without this message, a user may try to load the driver,
get an error message, and have no idea why the driver was not
enabled even though the hardware exists. If anything , -ENODEV
is less than perfect. Unfortunately there does not seem to be
a better error code, or at least I don't see one.

Guenter

Coincidentally, I was looking at this code on Friday.

Some HPE Proliant servers are disabling the AMD WDT in BIOS.  However,
sp5100_tco was still getting configured.  It was the lack of
"Watchdog hardware is disabled" message that helped clue us into
what was going on (Linux is enabling the WDT anyway.)

So, I liked that this message exists.

I'll send an RFC patch for this other issue as it orthogonal.
But just wanted to point out the message is useful.

I personally don't have a problem blacklisting on a system I encounter this. I take anything at "err" level as there is a firmware problem or a hardware problem that should be looked at.

As the message is genuinely useful as Jerry points out how about meeting in the middle at info or notice?


I really don't want to change it. It does point out a serious issue,
intentional or not. Anyone concerned or disturbed about the message
can easily block the module from loading, and others may rely on it.
From driver perspective it _is_ an error, and it should be treated
as such.

Guenter