Re: [PATCH Part2 RFC v4 09/40] x86/fault: Add support to dump RMP entry on fault

[Brijesh Singh]

On 7/8/21 11:58 AM, Dave Hansen wrote:>> Logically its going to be 
tricky to figure out which exact entry caused
> > the fault, hence I dump any non-zero entry. I understand it may dump
> > some useless.
>
> What's tricky about it?
>
> Sure, there's a possibility that more than one entry could contribute to
> a fault.  But, you always know *IF* an entry could contribute to a fault.
>
> I'm fine if you run through the logic, don't find a known reason
> (specific RMP entry) for the fault, and dump the whole table in that
> case.  But, unconditionally polluting the kernel log with noise isn't
> very nice for debugging.

The tricky part is to determine which undocumented bit to check to know 
that we should stop dump. I can go with your suggestion that first try 
with the known reasons and fallback to dump whole table for unknown 
reasons only.

thanks