Re: [PATCH v1] mm/hwpoison: set PageHWPoison after taking page lock in memory_failure_hugetlb()

[Andrew Morton]

On Wed,  9 Mar 2022 18:14:49 +0900 Naoya Horiguchi <naoya.horiguchi@xxxxxxxxx> wrote:

> There is a race condition between memory_failure_hugetlb() and hugetlb
> free/demotion, which causes setting PageHWPoison flag on the wrong page
> (which was a hugetlb when memory_failrue() was called, but was removed
> or demoted when memory_failure_hugetlb() is called).  This results in
> killing wrong processes.  So set PageHWPoison flag with holding page lock,

What are the runtime effects of this?  Do we think a -stable backport
is needed?

Are we missing a reported-by here?  I'm too lazy to hunt down who it was.