linux-kernel - [RFC PATCH v1 08/37] KVM: guest_memfd: Don't set FGP

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Message-ID: <dc5f58f5d3427b6291486a24061b6301761dda3d.1760731772.git.ackerleytng@google.com>
Date: Fri, 17 Oct 2025 13:11:49 -0700
From: Ackerley Tng <ackerleytng@...gle.com>
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Subject: [RFC PATCH v1 08/37] KVM: guest_memfd: Don't set FGP_ACCESSED when
 getting folios

guest_memfd folios don't care about accessed flags since the memory is
unevictable and there is no storage to write back to, hence, cleanup the
allocation path by not setting FGP_ACCESSED.

Signed-off-by: Ackerley Tng <ackerleytng@...gle.com>
[sean: split to separate patch, write changelog]
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 virt/kvm/guest_memfd.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
index 855e682041311..2a9e9220a48aa 100644
--- a/virt/kvm/guest_memfd.c
+++ b/virt/kvm/guest_memfd.c
@@ -167,14 +167,13 @@ static struct folio *kvm_gmem_get_folio(struct inode *inode, pgoff_t index)
 	 * Fast-path: See if folio is already present in mapping to avoid
 	 * policy_lookup.
 	 */
-	folio = __filemap_get_folio(inode->i_mapping, index,
-				    FGP_LOCK | FGP_ACCESSED, 0);
+	folio = filemap_lock_folio(inode->i_mapping, index);
 	if (!IS_ERR(folio))
 		return folio;
 
 	policy = kvm_gmem_get_folio_policy(GMEM_I(inode), index);
 	folio = __filemap_get_folio_mpol(inode->i_mapping, index,
-					 FGP_LOCK | FGP_ACCESSED | FGP_CREAT,
+					 FGP_LOCK | FGP_CREAT,
 					 mapping_gfp_mask(inode->i_mapping), policy);
 	mpol_cond_put(policy);
 
-- 
2.51.0.858.gf9c4a03a3a-goog