Commit 5130d450 authored by Fuad Tabba's avatar Fuad Tabba Committed by Marc Zyngier
Browse files

KVM: arm64: Seed pkvm_ownership_selftest vcpu memcache 



The hypercall handlers call pkvm_refill_memcache() to top up the
hyp_vcpu memcache before invoking __pkvm_host_{share,donate}_guest().
pkvm_ownership_selftest invokes those functions directly with a
static selftest_vcpu that has an empty memcache.

Seed selftest_vcpu's memcache from the prepopulated selftest
pages, leaving the remainder for selftest_vm.pool. Required by
the memcache-sufficiency pre-check added in the following
patches.

Assisted-by: Gemini:gemini-3.1-pro review-prompts
Signed-off-by: default avatarFuad Tabba <tabba@google.com>
Link: https://patch.msgid.link/20260501112149.2824881-5-tabba@google.com


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent d4d215e5

arch/arm64/kvm/hyp/nvhe/pkvm.c

+15 −1
Original line number Diff line number Diff line
@@ -752,17 +752,31 @@ static struct pkvm_hyp_vcpu selftest_vcpu = { 
struct pkvm_hyp_vcpu *init_selftest_vm(void *virt)

{

	struct hyp_page *p = hyp_virt_to_page(virt);

	unsigned long min_pages, seeded = 0;

	int i;



	selftest_vm.kvm.arch.mmu.vtcr = host_mmu.arch.mmu.vtcr;

	WARN_ON(kvm_guest_prepare_stage2(&selftest_vm, virt));



	/*

	 * Mirror pkvm_refill_memcache() for the share/donate pre-checks;

	 * the selftest invokes those functions directly and would

	 * otherwise see an empty memcache.

	 */

	min_pages = kvm_mmu_cache_min_pages(&selftest_vm.kvm.arch.mmu);



	for (i = 0; i < pkvm_selftest_pages(); i++) {

		if (p[i].refcount)

			continue;

		p[i].refcount = 1;

		if (seeded < min_pages) {

			push_hyp_memcache(&selftest_vcpu.vcpu.arch.pkvm_memcache,

					  hyp_page_to_virt(&p[i]), hyp_virt_to_phys);

			seeded++;

		} else {

			hyp_put_page(&selftest_vm.pool, hyp_page_to_virt(&p[i]));

		}

	}



	selftest_vm.kvm.arch.pkvm.handle = __pkvm_reserve_vm();

	insert_vm_table_entry(selftest_vm.kvm.arch.pkvm.handle, &selftest_vm);