Re: [PATCH v3 01/11] watchdog/hpwdt: Remove legacy NMI sourcing.

From: Ingo Molnar
Date: Fri Feb 16 2018 - 02:22:59 EST



* Jerry Hoemann <jerry.hoemann@xxxxxxx> wrote:

> Gen8 and prior Proliant systems supported the "CRU" interface
> to firmware. This interfaces allows linux to "call back" into firmware
> to source the cause of an NMI. This feature isn't fully utilized
> as the actual source of the NMI isn't printed, the driver only
> indicates that the source couldn't be determined when the call
> fails.
>
> With the advent of Gen9, iCRU replaces the CRU. The call back
> feature is no longer available in firmware. To be compatible and
> not attempt to call back into firmware on system not supporting CRU,
> the SMBIOS table is consulted to determine if it is safe to
> make the call back or not.
>
> This results in about half of the driver code being devoted
> to either making CRU calls or determing if it is safe to make
> CRU calls. As noted, the driver isn't really using the results of
> the CRU calls.
>
> As the CRU sourcing of the NMI isn't required for handling the
> NMI, remove the legacy (pre Gen9) NMI sourcing and the DMI code to
> determine if the system had the CRU interface.
>
> Signed-off-by: Jerry Hoemann <jerry.hoemann@xxxxxxx>
> ---
> drivers/watchdog/hpwdt.c | 490 +----------------------------------------------
> 1 file changed, 8 insertions(+), 482 deletions(-)

Acked-by: Ingo Molnar <mingo@xxxxxxxxxx>

Thanks,

Ingo