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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Subject: Re: [PATCH v7 1/6] mm:/Kconfig changes for migrate on fault for device pages Message-ID: References: <20260330043017.251808-1-mpenttil@redhat.com> <20260330043017.251808-2-mpenttil@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260330043017.251808-2-mpenttil@redhat.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: 51426160008 X-Stat-Signature: 8nad39bziyaxygnswxrce9nrn87mi4pw X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1774851645-386913 X-HE-Meta: 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 4EGqJFgL 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Mar 30, 2026 at 07:30:12AM +0300, mpenttil@redhat.com wrote: > From: Mika Penttilä > > With the unified HMM/migrate_device page table walk > migrate_device needs HMM enabled and HMM needs > MMU notifiers. Enable them explicitly to avoid > breaking random configs. You can use a lot more space in your commit logs, ending the lines so early reads a bit weird. > diff --git a/mm/Kconfig b/mm/Kconfig > index ebd8ea353687..583d92bba2e8 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -647,6 +647,7 @@ config MIGRATION > > config DEVICE_MIGRATION > def_bool MIGRATION && ZONE_DEVICE > + select HMM_MIRROR > > config ARCH_ENABLE_HUGEPAGE_MIGRATION > bool > @@ -1222,6 +1223,7 @@ config ZONE_DEVICE > config HMM_MIRROR > bool > depends on MMU > + select MMU_NOTIFIER But either way this really should go into the patch that actually adds the code dependency anyway.