Re: [PATCH v7 03/14] KVM: Documentation: Make note of the KVM_MEM_GUEST_MEMFD memslot flag

[Sean Christopherson <seanjc@google.com>]

On Thu, Feb 15, 2024, Anish Moorthy wrote:
>  This ioctl allows the user to create, modify or delete a guest physical
>  memory slot.  Bits 0-15 of "slot" specify the slot id and this value
> @@ -1382,12 +1383,16 @@ It is recommended that the lower 21 bits of guest_phys_addr and userspace_addr
>  be identical.  This allows large pages in the guest to be backed by large
>  pages in the host.
>  
> -The flags field supports two flags: KVM_MEM_LOG_DIRTY_PAGES and
> -KVM_MEM_READONLY.  The former can be set to instruct KVM to keep track of
> +The flags field supports three flags
> +
> +1.  KVM_MEM_LOG_DIRTY_PAGES: can be set to instruct KVM to keep track of
>  writes to memory within the slot.  See KVM_GET_DIRTY_LOG ioctl to know how to

This formatting is funky.  I suspect you are trying to avoid touching lines that
otherwise wouldn't be modified, but the end result is hard to read.  I would also
opportunistically clean up the wording in general, e.g.

1. KVM_MEM_LOG_DIRTY_PAGES: can be set to instruct KVM to keep track of writes
   to memory within the slot.  See KVM_GET_DIRTY_LOG ioctl for details.

> -use it.  The latter can be set, if KVM_CAP_READONLY_MEM capability allows it,
> +use it.
> +2.  KVM_MEM_READONLY: can be set, if KVM_CAP_READONLY_MEM capability allows it,
>  to make a new slot read-only.  In this case, writes to this memory will be
>  posted to userspace as KVM_EXIT_MMIO exits.
> +3.  KVM_MEM_GUEST_MEMFD: see KVM_SET_USER_MEMORY_REGION2. This flag is
> +incompatible with KVM_SET_USER_MEMORY_REGION.

This is now stale, as KVM_MEM_GUEST_MEMFD is also incompatible with READONLY.