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From: Kunwu Chan In-Reply-To: <87pldrtj1o.wl-maz@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Stat-Signature: hmp3sr4546y54qmxp817axcfrybqnhnp X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: E74D8140002 X-Rspam-User: X-HE-Tag: 1753271104-342852 X-HE-Meta: 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 OiztZpAo H1PD0c4jQ7BFhB+A= 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 2025/7/23 16:20, Marc Zyngier wrote: > On Tue, 22 Jul 2025 13:31:34 +0100, > Kunwu Chan wrote: >> On 2025/7/18 00:27, Fuad Tabba wrote: >>> Add arm64 architecture support for handling guest page faults on memory >>> slots backed by guest_memfd. >>> >>> This change introduces a new function, gmem_abort(), which encapsulates >>> the fault handling logic specific to guest_memfd-backed memory. The >>> kvm_handle_guest_abort() entry point is updated to dispatch to >>> gmem_abort() when a fault occurs on a guest_memfd-backed memory slot (as >>> determined by kvm_slot_has_gmem()). >>> >>> Until guest_memfd gains support for huge pages, the fault granule for >>> these memory regions is restricted to PAGE_SIZE. >> Since huge pages are not currently supported, would it be more >> friendly to define  sth like >> >> "#define GMEM_PAGE_GRANULE PAGE_SIZE" at the top (rather than >> hardcoding PAGE_SIZE) >> >>  and make it easier to switch to huge page support later? > No. PAGE_SIZE always has to be the fallback, no matter what. When (and > if) larger mappings get supported, there will be extra code for that > purpose, not just flipping a definition. > > Thanks, > > M. Got it, no questions here. Feel free to add my "Reviewed-by" tag to the patch. Reviewed-by: Tao Chan Thanks, TAO. --- “Life finds a way.”