On 6/24/2026 10:38 PM, Ackerley Tng wrote:

Binbin Wu [off-list ref] writes:

quoted

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quoted

+bool kvm_gmem_is_private(struct kvm *kvm, gfn_t gfn)
+{
+	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
+	struct inode *inode;
+
+	/*
+	 * If this gfn has no associated memslot, there's no chance of the gfn
+	 * being backed by private memory, since guest_memfd must be used for
+	 * private memory,

"guest_memfd must be used for private memory" is a bit confusing to me.

Hmm good point. Is the source of confusion that guest_memfd can be used
for both shared and private memory?

Yes.

Perhaps this can be rephrased as:

guest_memfd is the only provider of private memory and guest_memfd must
be used with a memslot, hence if there's no associated memslot, there's
no chance of this gfn being private.

LGTM.

quoted

quoted

and guest_memfd must be associated with some memslot.
+	 */
+	if (!slot)
+		return 0;
+

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