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 ioCFXNaw Z5rZ6MoLYqnFFFAeOsi0F5kzVGQHRTpKZIgGmiSkXGqKRgIbHUWoLOhvbK6aAKsAscwHOEWeWuulaYbziJ3ZFMgdAkhf9J3o3Wm3HQRBidSlFh+o1pl9dstNkqHZaBsUSmRnjQYsEIIQOxAVwfwjMnOxrajQBw83kM/IasMELztqfFb+xovTE9IWgM//+4FBgj/rI4WxUpg+3fzQiQndtlBMHTLOUDGaNkmTXAXIE5LynHNNwyEFwLTUT3SGOz8k8XWoSK3pLE7Sj4cTV/i07KF0O9nq34rC18IPivhzJwicBT5rEOBc0ioMcYgGwetuazx7sGZm75wwQCyZk5UZvnAVguuo0nf2rIZkT3EIgbfS8sL03bQMypYbpwCsxfmM33W44wBT8TC2XDWOUc+MrVEhH7TyaXD6J6hyWSfaZrG8uFbcRB3W+NkWUIDmgh99v4pBQHFItc9Dm1gnEaFdekVtyk5i3PZKNx9eLj0pK6n2Fum+Uq+Dt8mAnMro7WMNR+DNdCpIpz2qzjuuOtMv/bM1BhbAm96WYYSd/vYMnoaAqBMvCPCja1BGDdS2DPw4FerqSrTyNZCZWso8D0shZGFxsR/MSmNzQ7DpgfNkMAd134Velv3hucHtgZmwCKzxK2ptiMeQ0a+35RE+dSg+ZYhd+MBPT8MjaPHTQYjaqrUzpsThUnWlJRIBOPQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Jun 10, 2025 at 03:24:16PM +0200, David Hildenbrand wrote: > On 10.06.25 14:07, Lorenzo Stoakes wrote: > > OK so I think the best solution here is to just update check_ops_valid(), which > > was kind of sucky anyway (we check everywhere but walk_page_range_mm() to > > enforce the install pte thing). > > > > Let's do something like: > > > > #define OPS_MAY_INSTALL_PTE (1<<0) > > #define OPS_MAY_AVOID_LOCK (1<<1) > > > > and update check_ops_valid() to take a flags or maybe 'capabilities' field. > > > > Then check based on this e.g.: > > > > if (ops->install_pte && !(capabilities & OPS_MAY_INSTALL_PTE)) > > return false; > > > > if (ops->walk_lock == PGWALK_NOLOCK && !(capabilities & OPS_MAY_AVOID_LOCK)) > > return false; > > > > Hm. I mean, we really only want to allow this lockless check for > walk_kernel_page_table_range(), right? > > Having a walk_kernel_page_table_range_lockeless() might (or might not) be > better, to really only special-case this specific path. Agree completely, Dev - let's definitely do this. > > So, I am wondering if we should further start splitting the > kernel-page-table walker up from the mm walker, at least on the "entry" > function for now. How do you mean? > > -- > Cheers, > > David / dhildenb >