Re: [PATCH v4 1/2] x86/mce: Check for writes ignored in MCA_STATUS register

Borislav Petkov
2022-04-20T09:18:01Z

On Mon, Apr 18, 2022 at 08:24:35PM -0700, Smita Koralahalli wrote:
> Why are we checking this here? This flag (hw_injection_possible)
> is set to false inside prepare_msrs() called from
> smp_call_function_single().
> Should this check be done after the call to smp_call_function_single()?

Why would you do that then?

Is any of the code after

if (inj_type == SW_INJ) {
mce_log(m);
return 0;
}

worth running if hardware injection is not possible?

> Also, we already have inj_desc.err which returns error code to userspace
> when WRIG in status registers. Why is this flag needed?

To not do unnecessary work when you *know* hardware injection won't
work.

:-)

Btw, please trim your mails when you reply, just like I did.

Thx.

--
Regards/Gruss,
Boris.