RE: [PATCH] x86/mce: Set PG_hwpoison page flag to avoid the capture kernel panic

[Luck, Tony]

> Although I'm not sure that SGX memory or PMEM pages are expected to be
> included in kdump, but simply setting PageHWPoison does not work for them?
> (Maybe that depends on how kdump handles these types of memory.)

SGX/TDX pages can't be dumped. They are encrypted with no way for kdump to
get the key.

PMEM seems pointless (but I don't know what kdump does here).

> As for HugeTLB, kdump utility should parse the struct page and be aware of
> HugeTLB pages, so maybe setting PageHWPoison on the head page could work.

Or maybe kdump can take not of the PageHWPoison flag on the sub-page of the
huge page? It depends on whether there is any benefit to the dump to include the
not-poisoned parts of a huge page.


> I think that setting PageHWPoison outside hwpoison subsystem is OK here,
> because this is called just before calling panic() so it's expected to not
> conflict with other hwpoison-related code.

Thanks for the review.

-Tony