Re: [PATCH 1/1] ACPI/nfit: correct the badrange to be reported in nfit_handle_mce()

Dan Williams
2020-11-19T02:07:03Z

On Wed, Nov 18, 2020 at 5:53 PM Leizhen (ThunderTown)
<thunder.leizhen@huawei.com> wrote:
>
>
>
> On 2020/11/19 3:16, Dan Williams wrote:
> > On Wed, Nov 18, 2020 at 12:55 AM Leizhen (ThunderTown)
> > <thunder.leizhen@huawei.com> wrote:
> >>
> >>
> >>
> >> On 2020/11/18 16:41, Zhen Lei wrote:
> >>> The badrange to be reported should always cover mce->addr.
> >> Maybe I should change this description to:
> >> Make sure the badrange to be reported can always cover mce->addr.
> >
> > Yes, I like that better. Can you also say a bit more about how you
> > found this bug? As far as I can see this looks like -stable material.
>
> I found it when I was learning the code. I'm looking at it carefully.

Ok, good eye.

The impact of this one is somewhat mitigated by the fact that errors
are expanded to 512 byte blast radius, and error consumption maps 4k
around errors. I suspect few are trying to use the badblock list to do
fine grained recovery so this bug went unnoticed.