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charset="utf-8" Message-Id: <20261022-gmem-alternative-providers-v2-41-5dd1dc6c660a@google.com> References: <20261022-gmem-alternative-providers-v2-0-5dd1dc6c660a@google.com> In-Reply-To: <20261022-gmem-alternative-providers-v2-0-5dd1dc6c660a@google.com> To: Alex Williamson , Alexander Graf , Alexander Viro , Alexey Kardashevskiy , Andrew Morton , "Aneesh Kumar K.V" , Ashish Kalra , Baolin Wang , Baolu Lu , Bill Wendling , Borislav Petkov , Catalin Marinas , Christian Brauner , =?utf-8?q?Christian_K=C3=B6nig?= , Connor Williamson , Dave Hansen , Dave Jiang , David Hildenbrand , David Rientjes , David Woodhouse , Erdem Aktas , Frank van der Linden , Fred Griffoul , Fred Griffoul , Gregory Price , "H. Peter Anvin" , Hugh Dickins , Ingo Molnar , Jacob Pan , James Houghton , Jan Kara , Jason Gunthorpe , Jianxiong Gao , Joerg Roedel , Joey Gouly , John Starks , Jonathan Corbet , Justin Stitt , Kevin Tian , Lorenzo Stoakes , Marc Zyngier , Michael Roth , Mike Rapoport , Nathan Chancellor , Nick Desaulniers , Nicolin Chen , Oliver Upton , Paolo Bonzini , Pratyush Yadav , Randy Dunlap , Robin Murphy , Samiullah Khawaja , Sean Christopherson , Shuah Khan , Steffen Eiden , Steven Price , Suzuki K Poulose , Tarun Sahu , Thomas Gleixner , Tom Lendacky , Tycho Andersen , Vishal Annapurve , Vlastimil Babka , Will Deacon , Xu Yilun , Yan Zhao , Zenghui Yu , x86@kernel.org, Shuah Khan , 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, llvm@lists.linux.dev, Ackerley Tng X-Mailer: b4 0.17-dev X-Developer-Signature: v=1; a=ed25519-sha256; t=1792711665; l=995; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=ywimPr8xM8W5IWC+IFHzZM+XE9Py2m+UQJgTrzAxKZc=; b=AmJho2/OmL5iB6a3wmmUlrO/oEcg3/kVVcZkPZCjkwKxtxHbWU1NfSLey8pjERpooe/o5caEO cTmpBxuPY05Cn9MXbqAN6Hlr9/+SNa1XkP1V/8eVUvxLXLs831J+mRv 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 5741ff6ab94c6..c89df77df7146 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -1068,6 +1068,11 @@ 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; -- 2.56.0.257.gf7497c7d27-goog