Commit b638a9d0 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: selftests: Add a test for FEAT_IDST 

Add a very basic test checking that FEAT_IDST actually works for
the {GMID,SMIDR,CSSIDR2}_EL1 registers.

Link: https://patch.msgid.link/20260108173233.2911955-10-maz@kernel.org


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent 592dc2c0

tools/testing/selftests/kvm/Makefile.kvm

+1 −0
Original line number Diff line number Diff line
@@ -175,6 +175,7 @@ TEST_GEN_PROGS_arm64 += arm64/vgic_irq 
TEST_GEN_PROGS_arm64 += arm64/vgic_lpi_stress

TEST_GEN_PROGS_arm64 += arm64/vpmu_counter_access

TEST_GEN_PROGS_arm64 += arm64/no-vgic-v3

TEST_GEN_PROGS_arm64 += arm64/idreg-idst

TEST_GEN_PROGS_arm64 += arm64/kvm-uuid

TEST_GEN_PROGS_arm64 += access_tracking_perf_test

TEST_GEN_PROGS_arm64 += arch_timer

tools/testing/selftests/kvm/arm64/idreg-idst.c

0 → 100644
+117 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



/*

 * Access all FEAT_IDST-handled registers that depend on more than

 * just FEAT_AA64, and fail if we don't get an a trap with an 0x18 EC.

 */



#include <test_util.h>

#include <kvm_util.h>

#include <processor.h>



static volatile bool sys64, undef;



#define __check_sr_read(r)					\

	({							\

		uint64_t val;					\

								\

		sys64 = false;					\

		undef = false;					\

		dsb(sy);					\

		val = read_sysreg_s(SYS_ ## r);			\

		val;						\

	})



/* Fatal checks */

#define check_sr_read(r)					\

	do {							\

		__check_sr_read(r);				\

		__GUEST_ASSERT(!undef, #r " unexpected UNDEF");	\

		__GUEST_ASSERT(sys64, #r " didn't trap");	\

	} while(0)





static void guest_code(void)

{

	check_sr_read(CCSIDR2_EL1);

	check_sr_read(SMIDR_EL1);

	check_sr_read(GMID_EL1);



	GUEST_DONE();

}



static void guest_sys64_handler(struct ex_regs *regs)

{

	sys64 = true;

	undef = false;

	regs->pc += 4;

}



static void guest_undef_handler(struct ex_regs *regs)

{

	sys64 = false;

	undef = true;

	regs->pc += 4;

}



static void test_run_vcpu(struct kvm_vcpu *vcpu)

{

	struct ucall uc;



	do {

		vcpu_run(vcpu);



		switch (get_ucall(vcpu, &uc)) {

		case UCALL_ABORT:

			REPORT_GUEST_ASSERT(uc);

			break;

		case UCALL_PRINTF:

			printf("%s", uc.buffer);

			break;

		case UCALL_DONE:

			break;

		default:

			TEST_FAIL("Unknown ucall %lu", uc.cmd);

		}

	} while (uc.cmd != UCALL_DONE);

}



static void test_guest_feat_idst(void)

{

	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm;



	/* This VM has no MTE, no SME, no CCIDX */

	vm = vm_create_with_one_vcpu(&vcpu, guest_code);



	vm_init_descriptor_tables(vm);

	vcpu_init_descriptor_tables(vcpu);



	vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT,

				ESR_ELx_EC_SYS64, guest_sys64_handler);

	vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT,

				ESR_ELx_EC_UNKNOWN, guest_undef_handler);



	test_run_vcpu(vcpu);



	kvm_vm_free(vm);

}



int main(int argc, char *argv[])

{

	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm;

	uint64_t mmfr2;



	test_disable_default_vgic();



	vm = vm_create_with_one_vcpu(&vcpu, NULL);

	mmfr2 = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64MMFR2_EL1));

	__TEST_REQUIRE(FIELD_GET(ID_AA64MMFR2_EL1_IDS, mmfr2) > 0,

		       "FEAT_IDST not supported");

	kvm_vm_free(vm);



	test_guest_feat_idst();



	return 0;

}