linux-kernel - Re: [PATCH 2/3] KVM: selftests: Add TDP unmap helpers

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Message-ID: <aXFRaQs5nGpTN53Y@google.com>
Date: Wed, 21 Jan 2026 14:21:29 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Kevin Cheng <chengkev@...gle.com>
Cc: pbonzini@...hat.com, kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	yosry.ahmed@...ux.dev
Subject: Re: [PATCH 2/3] KVM: selftests: Add TDP unmap helpers

On Wed, Jan 21, 2026, Kevin Cheng wrote:
> Add __virt_pg_unmap(), __tdp_unmap(), and tdp_unmap() as counterparts
> to the existing __virt_pg_map(), __tdp_map(), and tdp_map() functions.
> These helpers allow tests to selectively unmap pages from the TDP/NPT,
> enabling testing of NPT faults for unmapped pages.

This is both overkill and insufficient, just do:

	*tdp_get_pte(vm, <addr>) &= ~PTE_PRESENT_MASK(&vm->stage2_mmu);

Then when a test wants to validate more than just !PRESENT we don't need to add
another API.