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From: Muchun Song In-Reply-To: <20260709112520.24857-2-lizhe.67@bytedance.com> Date: Tue, 14 Jul 2026 10:25:26 +0800 Cc: akpm@linux-foundation.org, apopple@nvidia.com, arnd@arndb.de, balbirs@nvidia.com, bp@alien8.de, dave.hansen@linux.intel.com, david@kernel.org, kees@kernel.org, mingo@redhat.com, rppt@kernel.org, tglx@kernel.org, linux-arch@vger.kernel.org, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org Content-Transfer-Encoding: 7bit Message-Id: <287F70E5-78F2-4C52-99A4-E72CA16C7635@linux.dev> References: <20260709112520.24857-1-lizhe.67@bytedance.com> <20260709112520.24857-2-lizhe.67@bytedance.com> To: Li Zhe X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: CAD6780003 X-Stat-Signature: 5op4hef8ah5hrxkx61c87ha366pzg4qg X-HE-Tag: 1783995968-277233 X-HE-Meta: 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 8SK13JMe yNXktZMSh9X22JryfqSRytB0bDo38WyunpQ5jDp5lc9edv/3+gTN4E+ej1O8h/wOW0JMoODvYcx5F+JNOicKASi6vq0dIpbooBPwAPXRCezWKSJ6Cl05xF8TKw1QjDV/owqlUHzeNevINY92Fyy1bam8YxHW/OYP1zRNAE02WAqrUNAZGUl/MO5GsCL5JyW71ld7S4/nziRqiq2s3HGSmvN7dCSukOP0Kp5ZnmjIwlo+oREHVNxjppQ9taX8kvqgP/PawTnD8qcbMagkb+SnHJ4VMcNpITFuQXyu9pIsKr16yLJ04DdBT/pvFBgVxzFl4JpZj7Wfvw5Rtg/1Pnu3boL/RDa/Bhtq/gliT Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On Jul 9, 2026, at 19:25, Li Zhe wrote: > > The comment in __init_zone_device_page() still uses the old > MEMORY_TYPE_* names and implies that FS_DAX pages regain a > refcount of 1 in the free path. That no longer matches the code. > > Update the comment to describe the current policy correctly: > MEMORY_DEVICE_GENERIC pages regain a refcount of 1 in the free path, > while the remaining ZONE_DEVICE types start from 0 here and raise the > count again when the allocator or driver hands the page out. > > No functional change intended. > > Signed-off-by: Li Zhe > Reviewed-by: David Hildenbrand (Arm) > Reviewed-by: Alistair Popple Reviewed-by: Muchun Song