Re: [PATCH v7 09/42] KVM: guest_memfd: Add base support for KVM_SET_MEMORY_ATTRIBUTES2

On Fri, May 22, 2026 at 05:17:51PM -0700, Ackerley Tng via B4 Relay wrote:

From: Ackerley Tng <redacted>

Introduce base support for KVM_SET_MEMORY_ATTRIBUTES2 in guest_memfd, which
just updates attributes tracked by guest_memfd.

Validate input fields in general. Guard usage of KVM_SET_MEMORY_ATTRIBUTES2
by making sure requested attributes are supported for this instance of kvm.

A new KVM_SET_MEMORY_ATTRIBUTES2 is defined to support writes (unlike
KVM_SET_MEMORY_ATTRIBUTES) in addition to reads so it can provide error
details to userspace. This will be used in a later patch.

The two ioctls use their corresponding structs with no overlap, but
backward compatibility is baked in for future support of
KVM_SET_MEMORY_ATTRIBUTES2 and struct kvm_memory_attributes2 in the VM
ioctl.

The process of setting memory attributes is set up such that the later half
will not fail due to allocation. Any necessary checks are performed before
the point of no return.

Co-developed-by: Vishal Annapurve <redacted>
Signed-off-by: Vishal Annapurve <redacted>
Co-developed-by: Sean Christoperson <seanjc@google.com>
Signed-off-by: Sean Christoperson <seanjc@google.com>

Typo on the "person".

(Sent this earlier but looks like some of my emails never hit the
list so re-sending. Apologies if this is a dupe).

Thanks,

Mike

Reviewed-by: Fuad Tabba <redacted>
Signed-off-by: Ackerley Tng <redacted>
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