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charset="utf-8" Message-Id: <20261106-gmem-alternative-providers-v3-40-8484dde66a7e@google.com> References: <20261106-gmem-alternative-providers-v3-0-8484dde66a7e@google.com> In-Reply-To: <20261106-gmem-alternative-providers-v3-0-8484dde66a7e@google.com> To: Alexey Kardashevskiy , "Aneesh Kumar K.V" , Christian Brauner , David Hildenbrand , David Woodhouse , Fred Griffoul , Jacob Pan , Jianxiong Gao , John Starks , Michael Roth , Paolo Bonzini , Samiullah Khawaja , Sean Christopherson , Suzuki K Poulose , Tarun Sahu , Vishal Annapurve , Xu Yilun , Fuad Tabba Cc: kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Ackerley Tng X-Mailer: b4 0.17-dev X-Developer-Signature: v=1; a=ed25519-sha256; t=1794011810; l=995; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=RMoXxdr7unZnobL7R1i/MK8zqw1q/jitBNuF2OvUGw8=; b=hjk6HdU81k97DczNhIQxswAsxYsu4tIqPkDlpmZd+T6wio0f6skkcsf8gsFCP0CMvMeZH6Uiq yEe+MejhQ7bCc8jLcDgoJYyK2pebq3F6/hjkDqs/RM2tzA/djMSle1h X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com Content-Transfer-Encoding: 7bit From: Ackerley Tng Add a TODO comment noting that PFN mode does not use page-cache folios, so ->error_remove_folio() will not be called by the core memory failure infrastructure when physical memory errors occur. Signed-off-by: Ackerley Tng --- virt/kvm/guest_memfd.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index 501c3e250fc98..ffe1508985d61 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -1127,6 +1127,11 @@ static int kvm_gmem_migrate_folio(struct address_space *mapping, return -EINVAL; } +/* + * TODO: Support memory failure notification for PFN mode. In PFN mode, memory + * is not backed by page cache folios, so ->error_remove_folio() will not be + * invoked by the core memory failure handler. + */ static int kvm_gmem_error_folio(struct address_space *mapping, struct folio *folio) { struct inode *inode = mapping->host; -- 2.56.0.455.g6c5a503b38-goog