Commit 5bab0875 authored by Christoph Schlameuss's avatar Christoph Schlameuss Committed by Janosch Frank
Browse files

selftests: kvm: s390: Add VM run test case 



Add test case running code interacting with registers within a
ucontrol VM.

* Add uc_gprs test case

The test uses the same VM setup using the fixture and debug macros
introduced in earlier patches in this series.

Signed-off-by: default avatarChristoph Schlameuss <schlameuss@linux.ibm.com>
Reviewed-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20240807154512.316936-7-schlameuss@linux.ibm.com


[frankja@linux.ibm.com: Removed leftover comment line]
Signed-off-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Message-ID: <20240807154512.316936-7-schlameuss@linux.ibm.com>
parent 100932fc

tools/testing/selftests/kvm/s390x/ucontrol_test.c

+125 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
 * Authors:

 *  Christoph Schlameuss <schlameuss@linux.ibm.com>

 */

#include "debug_print.h"

#include "kselftest_harness.h"

#include "kvm_util.h"

#include "processor.h"
@@ -40,6 +41,23 @@ void require_ucontrol_admin(void) 
	TEST_REQUIRE(kvm_has_cap(KVM_CAP_S390_UCONTROL));

}



/* Test program setting some registers and looping */

extern char test_gprs_asm[];

asm("test_gprs_asm:\n"

	"xgr	%r0, %r0\n"

	"lgfi	%r1,1\n"

	"lgfi	%r2,2\n"

	"lgfi	%r3,3\n"

	"lgfi	%r4,4\n"

	"lgfi	%r5,5\n"

	"lgfi	%r6,6\n"

	"lgfi	%r7,7\n"

	"0:\n"

	"	diag	0,0,0x44\n"

	"	ahi	%r0,1\n"

	"	j	0b\n"

);



FIXTURE(uc_kvm)

{

	struct kvm_s390_sie_block *sie_block;
@@ -204,4 +222,111 @@ TEST(uc_cap_hpage) 
	close(kvm_fd);

}



/* verify SIEIC exit

 * * fail on codes not expected in the test cases

 */

static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self)

{

	struct kvm_s390_sie_block *sie_block = self->sie_block;

	struct kvm_run *run = self->run;



	/* check SIE interception code */

	pr_info("sieic: 0x%.2x 0x%.4x 0x%.4x\n",

		run->s390_sieic.icptcode,

		run->s390_sieic.ipa,

		run->s390_sieic.ipb);

	switch (run->s390_sieic.icptcode) {

	case ICPT_INST:

		/* end execution in caller on intercepted instruction */

		pr_info("sie instruction interception\n");

		return false;

	case ICPT_OPEREXC:

		/* operation exception */

		TEST_FAIL("sie exception on %.4x%.8x", sie_block->ipa, sie_block->ipb);

	default:

		TEST_FAIL("UNEXPECTED SIEIC CODE %d", run->s390_sieic.icptcode);

	}

	return true;

}



/* verify VM state on exit */

static bool uc_handle_exit(FIXTURE_DATA(uc_kvm) * self)

{

	struct kvm_run *run = self->run;



	switch (run->exit_reason) {

	case KVM_EXIT_S390_SIEIC:

		return uc_handle_sieic(self);

	default:

		pr_info("exit_reason %2d not handled\n", run->exit_reason);

	}

	return true;

}



/* run the VM until interrupted */

static int uc_run_once(FIXTURE_DATA(uc_kvm) * self)

{

	int rc;



	rc = ioctl(self->vcpu_fd, KVM_RUN, NULL);

	print_run(self->run, self->sie_block);

	print_regs(self->run);

	pr_debug("run %d / %d %s\n", rc, errno, strerror(errno));

	return rc;

}



static void uc_assert_diag44(FIXTURE_DATA(uc_kvm) * self)

{

	struct kvm_s390_sie_block *sie_block = self->sie_block;



	/* assert vm was interrupted by diag 0x0044 */

	TEST_ASSERT_EQ(KVM_EXIT_S390_SIEIC, self->run->exit_reason);

	TEST_ASSERT_EQ(ICPT_INST, sie_block->icptcode);

	TEST_ASSERT_EQ(0x8300, sie_block->ipa);

	TEST_ASSERT_EQ(0x440000, sie_block->ipb);

}



TEST_F(uc_kvm, uc_gprs)

{

	struct kvm_sync_regs *sync_regs = &self->run->s.regs;

	struct kvm_run *run = self->run;

	struct kvm_regs regs = {};



	/* Set registers to values that are different from the ones that we expect below */

	for (int i = 0; i < 8; i++)

		sync_regs->gprs[i] = 8;

	run->kvm_dirty_regs |= KVM_SYNC_GPRS;



	/* copy test_gprs_asm to code_hva / code_gpa */

	TH_LOG("copy code %p to vm mapped memory %p / %p",

	       &test_gprs_asm, (void *)self->code_hva, (void *)self->code_gpa);

	memcpy((void *)self->code_hva, &test_gprs_asm, PAGE_SIZE);



	/* DAT disabled + 64 bit mode */

	run->psw_mask = 0x0000000180000000ULL;

	run->psw_addr = self->code_gpa;



	/* run and expect interception of diag 44 */

	ASSERT_EQ(0, uc_run_once(self));

	ASSERT_EQ(false, uc_handle_exit(self));

	uc_assert_diag44(self);



	/* Retrieve and check guest register values */

	ASSERT_EQ(0, ioctl(self->vcpu_fd, KVM_GET_REGS, &regs));

	for (int i = 0; i < 8; i++) {

		ASSERT_EQ(i, regs.gprs[i]);

		ASSERT_EQ(i, sync_regs->gprs[i]);

	}



	/* run and expect interception of diag 44 again */

	ASSERT_EQ(0, uc_run_once(self));

	ASSERT_EQ(false, uc_handle_exit(self));

	uc_assert_diag44(self);



	/* check continued increment of register 0 value */

	ASSERT_EQ(0, ioctl(self->vcpu_fd, KVM_GET_REGS, &regs));

	ASSERT_EQ(1, regs.gprs[0]);

	ASSERT_EQ(1, sync_regs->gprs[0]);

}



TEST_HARNESS_MAIN