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dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=dR0xSXmc; spf=none (imf22.hostedemail.com: domain of peterx@redhat.com has no SPF policy when checking 216.205.24.124) smtp.mailfrom=peterx@redhat.com; dmarc=pass (policy=none) header.from=redhat.com X-Rspamd-Server: rspam06 X-HE-Tag: 1632764360-949151 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000003, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Sep 27, 2021 at 10:34:06AM -0700, Axel Rasmussen wrote: > One possibility would be to MADV_NOHUGEPAGE the regions, which at > least would fix the immediate flakiness. Then we could spend some time > adding a test case which specifically targets THP interactions? (I do > think we want test coverage of that in the end, but with the current > tests it's kind of "accidental".) If we can't reproduce it with khugepaged yet, I'd think we can also consider keep torturing thp with this patch and at the meantime look for a clean approach? Now it's only the event test failing, if we apply NOHUGEPAGE we give up thp for all. -- Peter Xu