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dkim=pass header.d=ellerman.id.au header.s=201909 header.b="Dj5/0PZN"; dmarc=none; spf=pass (imf02.hostedemail.com: domain of mpe@ellerman.id.au designates 150.107.74.76 as permitted sender) smtp.mailfrom=mpe@ellerman.id.au X-Rspamd-Server: rspam04 X-Rspam-User: X-HE-Tag: 1660908158-345768 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000404, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Mike Kravetz writes: > On 08/16/22 22:43, Andrew Morton wrote: >> On Wed, 17 Aug 2022 03:31:37 +0000 "Wang, Haiyue" wrote: >> >> > > > } >> > > >> > > I would be better to fix this for real at those three client code sites? >> > >> > Then 5.19 will break for a while to wait for the final BIG patch ? >> >> If that's the proposal then your [1/2] should have had a cc:stable and >> changelog words describing the plan for 6.0. >> >> But before we do that I'd like to see at least a prototype of the final >> fixes to s390 and hugetlb, so we can assess those as preferable for >> backporting. I don't think they'll be terribly intrusive or risky? > > I will start on adding follow_huge_pgd() support. Although, I may need > some help with verification from the powerpc folks, as that is the only > architecture which supports hugetlb pages at that level. > > mpe any suggestions? I'm happy to test. I have a system where I can allocate 1GB huge pages. I'm not sure how to actually test this path though. I hacked up the vm/migration.c test to allocate 1GB hugepages, but I can't see it going through follow_huge_pgd() (using ftrace). Maybe I hacked it up badly, I'll have a closer look on Monday. But if you have any tips on how to trigger that path let me know :) cheers