Re: [kvm-unit-tests PATCH 8/8] s390x: sie: Add PV diag test

[Claudio Imbrenda <imbrenda@linux.ibm.com>]

On Tue, 23 Nov 2021 10:39:56 +0000
Janosch Frank <frankja@linux.ibm.com> wrote:

> Let's start testing the format 4 (PV) SIE via the diagnose
> instructions since most of them are pretty simple to handle.
> 
> The tests check for the intercept values like ipa/ipb and icptcode as
> well as the values in the registers and handling of the exception
> injection.
> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

> ---
>  s390x/Makefile                             |   7 +
>  s390x/pv-diags.c                           | 240 +++++++++++++++++++++
>  s390x/snippets/asm/snippet-pv-diag-288.S   |  25 +++
>  s390x/snippets/asm/snippet-pv-diag-500.S   |  39 ++++
>  s390x/snippets/asm/snippet-pv-diag-yield.S |   7 +
>  5 files changed, 318 insertions(+)
>  create mode 100644 s390x/pv-diags.c
>  create mode 100644 s390x/snippets/asm/snippet-pv-diag-288.S
>  create mode 100644 s390x/snippets/asm/snippet-pv-diag-500.S
>  create mode 100644 s390x/snippets/asm/snippet-pv-diag-yield.S
> 
> diff --git a/s390x/Makefile b/s390x/Makefile
> index 55e6d962..4f2374a5 100644
> --- a/s390x/Makefile
> +++ b/s390x/Makefile
> @@ -26,6 +26,8 @@ tests += $(TEST_DIR)/edat.elf
>  tests += $(TEST_DIR)/mvpg-sie.elf
>  tests += $(TEST_DIR)/spec_ex-sie.elf
>  
> +pv-tests += $(TEST_DIR)/pv-diags.elf
> +
>  ifneq ($(HOST_KEY_DOCUMENT),)
>  ifneq ($(GEN_SE_HEADER),)
>  tests += $(pv-tests)
> @@ -98,6 +100,11 @@ snippet_lib = $(snippet_asmlib) lib/auxinfo.o
>  $(TEST_DIR)/mvpg-sie.elf: snippets = $(SNIPPET_DIR)/c/mvpg-snippet.gbin
>  $(TEST_DIR)/spec_ex-sie.elf: snippets = $(SNIPPET_DIR)/c/spec_ex.gbin
>  
> +$(TEST_DIR)/pv-diags.elf: pv-snippets += $(SNIPPET_DIR)/asm/snippet-pv-diag-yield.gbin
> +$(TEST_DIR)/pv-diags.elf: pv-snippets += $(SNIPPET_DIR)/asm/snippet-pv-diag-288.gbin
> +$(TEST_DIR)/pv-diags.elf: pv-snippets += $(SNIPPET_DIR)/asm/snippet-pv-diag-500.gbin
> +
> +
>  ifneq ($(GEN_SE_HEADER),)
>  snippets += $(pv-snippets)
>  tests += $(pv-tests)
> diff --git a/s390x/pv-diags.c b/s390x/pv-diags.c
> new file mode 100644
> index 00000000..82288943
> --- /dev/null
> +++ b/s390x/pv-diags.c
> @@ -0,0 +1,240 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * PV virtualization interception tests for diagnose instructions.
> + *
> + * Copyright (c) 2021 IBM Corp
> + *
> + * Authors:
> + *  Janosch Frank <frankja@linux.ibm.com>
> + */
> +#include <libcflat.h>
> +#include <asm/asm-offsets.h>
> +#include <asm-generic/barrier.h>
> +#include <asm/interrupt.h>
> +#include <asm/pgtable.h>
> +#include <mmu.h>
> +#include <asm/page.h>
> +#include <asm/facility.h>
> +#include <asm/mem.h>
> +#include <asm/sigp.h>
> +#include <smp.h>
> +#include <alloc_page.h>
> +#include <vm.h>
> +#include <vmalloc.h>
> +#include <sclp.h>
> +#include <snippet.h>
> +#include <sie.h>
> +#include <uv.h>
> +#include <asm/uv.h>
> +
> +static u8 *guest;
> +static u8 *guest_instr;
> +static struct vm vm;
> +
> +uint64_t tweak[2] = {0x42, 0x00};
> +
> +static void setup_vmem(void)
> +{
> +	uint64_t asce;
> +
> +	/* We need to have a valid primary ASCE to run guests. */
> +	setup_vm();
> +
> +	/* Set P bit in ASCE as it is required for SE guests */
> +	asce = stctg(1) | ASCE_P;
> +	lctlg(1, asce);
> +
> +	/* Copy ASCE into home space CR */
> +	lctlg(13, asce);
> +}
> +
> +
> +static void init_guest(const char *gbin, const char *hdr, uint64_t gbin_len,
> +		       uint64_t hdr_len)
> +{
> +	uv_create_guest(&vm);
> +	uv_set_se_hdr(vm.uv.vm_handle, (void *)hdr, hdr_len);
> +
> +	/* Copy test image to guest memory */
> +	memcpy(guest_instr, gbin, gbin_len);
> +
> +	uv_unpack(&vm, SNIPPET_ENTRY_ADDR, gbin_len, tweak[0]);
> +	uv_verify_load(&vm);
> +
> +	/* Manually import lowcore */
> +	uv_import(vm.uv.vm_handle, (uint64_t)guest);
> +	uv_import(vm.uv.vm_handle, (uint64_t)(guest + PAGE_SIZE));
> +}
> +
> +static void setup_guest(void)
> +{
> +	setup_vmem();
> +
> +	/* Allocate 1MB as guest memory */
> +	guest = alloc_pages(8);
> +	memset(guest, 0, HPAGE_SIZE);
> +	/* The first two pages are the lowcore */
> +	guest_instr = guest + SNIPPET_ENTRY_ADDR;
> +
> +	sie_guest_create(&vm, (uint64_t)guest, HPAGE_SIZE);
> +	/* FMT4 needs a ESCA */
> +	sie_guest_sca_create(&vm);
> +
> +	uv_init();
> +}
> +
> +static void test_diag_500(void)
> +{
> +	extern const char SNIPPET_NAME_START(asm, snippet_pv_diag_500)[];
> +	extern const char SNIPPET_NAME_END(asm, snippet_pv_diag_500)[];
> +	extern const char SNIPPET_HDR_START(asm, snippet_pv_diag_500)[];
> +	extern const char SNIPPET_HDR_END(asm, snippet_pv_diag_500)[];
> +	int size_hdr = SNIPPET_HDR_LEN(asm, snippet_pv_diag_500);
> +	int size_gbin = SNIPPET_LEN(asm, snippet_pv_diag_500);
> +
> +	report_prefix_push("diag 0x500");
> +
> +	init_guest(SNIPPET_NAME_START(asm, snippet_pv_diag_500),
> +		   SNIPPET_HDR_START(asm, snippet_pv_diag_500),
> +		   size_gbin, size_hdr);
> +
> +	sie(&vm);
> +	report(vm.sblk->icptcode == ICPT_PV_INSTR && vm.sblk->ipa == 0x8302 &&
> +	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x500,
> +	       "intercept values");
> +	report(vm.save_area.guest.grs[1] == 1 &&
> +	       vm.save_area.guest.grs[2] == 2 &&
> +	       vm.save_area.guest.grs[3] == 3 &&
> +	       vm.save_area.guest.grs[4] == 4,
> +	       "register values");
> +	/*
> +	 * Check if we can inject a PGM operand which we are always
> +	 * allowed to do after a diag500 exit.
> +	 */
> +	vm.sblk->iictl = IICTL_CODE_OPERAND;
> +	sie(&vm);
> +	report(vm.sblk->icptcode == ICPT_PV_NOTIFY && vm.sblk->ipa == 0x8302 &&
> +	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x9c
> +	       && vm.save_area.guest.grs[0] == PGM_INT_CODE_OPERAND,
> +	       "operand exception");
> +
> +	/*
> +	 * Check if we can inject a PGM specification which we are always
> +	 * allowed to do after a diag500 exit.
> +	 */
> +	sie(&vm);
> +	vm.sblk->iictl = IICTL_CODE_SPECIFICATION;
> +	/* Inject PGM, next exit should be 9c */
> +	sie(&vm);
> +	report(vm.sblk->icptcode == ICPT_PV_NOTIFY && vm.sblk->ipa == 0x8302 &&
> +	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x9c
> +	       && vm.save_area.guest.grs[0] == PGM_INT_CODE_SPECIFICATION,
> +	       "specification exception");
> +
> +	/* No need for cleanup, just tear down the VM */
> +	uv_destroy_guest(&vm);
> +
> +	report_prefix_pop();
> +}
> +
> +
> +static void test_diag_288(void)
> +{
> +	extern const char SNIPPET_NAME_START(asm, snippet_pv_diag_288)[];
> +	extern const char SNIPPET_NAME_END(asm, snippet_pv_diag_288)[];
> +	extern const char SNIPPET_HDR_START(asm, snippet_pv_diag_288)[];
> +	extern const char SNIPPET_HDR_END(asm, snippet_pv_diag_288)[];
> +	int size_hdr = SNIPPET_HDR_LEN(asm, snippet_pv_diag_288);
> +	int size_gbin = SNIPPET_LEN(asm, snippet_pv_diag_288);
> +
> +	report_prefix_push("diag 0x288");
> +
> +	init_guest(SNIPPET_NAME_START(asm, snippet_pv_diag_288),
> +		   SNIPPET_HDR_START(asm, snippet_pv_diag_288),
> +		   size_gbin, size_hdr);
> +
> +	sie(&vm);
> +	report(vm.sblk->icptcode == ICPT_PV_INSTR && vm.sblk->ipa == 0x8302 &&
> +	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x288,
> +	       "intercept values");
> +	report(vm.save_area.guest.grs[0] == 1 &&
> +	       vm.save_area.guest.grs[1] == 2 &&
> +	       vm.save_area.guest.grs[2] == 3,
> +	       "register values");
> +
> +	/*
> +	 * Check if we can inject a PGM spec which we are always
> +	 * allowed to do after a diag288 exit.
> +	 */
> +	vm.sblk->iictl = IICTL_CODE_SPECIFICATION;
> +	sie(&vm);
> +	report(vm.sblk->icptcode == ICPT_PV_NOTIFY && vm.sblk->ipa == 0x8302 &&
> +	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x9c
> +	       && vm.save_area.guest.grs[0] == PGM_INT_CODE_SPECIFICATION,
> +	       "specification exception");
> +
> +	/* No need for cleanup, just tear down the VM */
> +	uv_destroy_guest(&vm);
> +
> +	report_prefix_pop();
> +}
> +
> +static void test_diag_yield(void)
> +{
> +	extern const char SNIPPET_NAME_START(asm, snippet_pv_diag_yield)[];
> +	extern const char SNIPPET_NAME_END(asm, snippet_pv_diag_yield)[];
> +	extern const char SNIPPET_HDR_START(asm, snippet_pv_diag_yield)[];
> +	extern const char SNIPPET_HDR_END(asm, snippet_pv_diag_yield)[];
> +	int size_hdr = SNIPPET_HDR_LEN(asm, snippet_pv_diag_yield);
> +	int size_gbin = SNIPPET_LEN(asm, snippet_pv_diag_yield);
> +
> +	report_prefix_push("diag yield");
> +
> +	init_guest(SNIPPET_NAME_START(asm, snippet_pv_diag_yield),
> +		   SNIPPET_HDR_START(asm, snippet_pv_diag_yield),
> +		   size_gbin, size_hdr);
> +
> +	/* 0x44 */
> +	report_prefix_push("0x44");
> +	sie(&vm);
> +	report(vm.sblk->icptcode == ICPT_PV_NOTIFY && vm.sblk->ipa == 0x8302 &&
> +	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x44,
> +	       "intercept values");
> +	report_prefix_pop();
> +
> +	/* 0x9c */
> +	report_prefix_push("0x9c");
> +	sie(&vm);
> +	report(vm.sblk->icptcode == ICPT_PV_NOTIFY && vm.sblk->ipa == 0x8302 &&
> +	       vm.sblk->ipb == 0x50000000 && vm.save_area.guest.grs[5] == 0x9c,
> +	       "intercept values");
> +	report(vm.save_area.guest.grs[0] == 42, "r1 correct");
> +	report_prefix_pop();
> +
> +	uv_destroy_guest(&vm);
> +	report_prefix_pop();
> +}
> +
> +
> +int main(void)
> +{
> +	report_prefix_push("pv-diags");
> +	if (!test_facility(158)) {
> +		report_skip("UV Call facility unavailable");
> +		goto done;
> +	}
> +	if (!sclp_facilities.has_sief2) {
> +		report_skip("SIEF2 facility unavailable");
> +		goto done;
> +	}
> +
> +	setup_guest();
> +	test_diag_yield();
> +	test_diag_288();
> +	test_diag_500();
> +	sie_guest_destroy(&vm);
> +
> +done:
> +	report_prefix_pop();
> +	return report_summary();
> +}
> diff --git a/s390x/snippets/asm/snippet-pv-diag-288.S b/s390x/snippets/asm/snippet-pv-diag-288.S
> new file mode 100644
> index 00000000..e3e63121
> --- /dev/null
> +++ b/s390x/snippets/asm/snippet-pv-diag-288.S
> @@ -0,0 +1,25 @@
> +#include <asm/asm-offsets.h>
> +.section .text
> +
> +/* Clean and pre-load registers that are used for diag 288 */
> +xgr	%r0, %r0
> +xgr	%r1, %r1
> +xgr	%r3, %r3
> +lghi	%r0, 1
> +lghi	%r1, 2
> +lghi	%r2, 3
> +
> +/* Let's jump to the pgm exit label on a PGM */
> +larl	%r4, exit_pgm
> +stg     %r4, GEN_LC_PGM_NEW_PSW + 8
> +
> +/* Execute the diag288 */
> +diag	%r0, %r2, 0x288
> +
> +/* Force exit if we don't get a PGM */
> +diag	0, 0, 0x44
> +
> +/* Communicate the PGM code via diag9c(easiest) */
> +exit_pgm:
> +lh	%r1, GEN_LC_PGM_INT_CODE
> +diag	%r1, 0, 0x9c
> diff --git a/s390x/snippets/asm/snippet-pv-diag-500.S b/s390x/snippets/asm/snippet-pv-diag-500.S
> new file mode 100644
> index 00000000..50c06779
> --- /dev/null
> +++ b/s390x/snippets/asm/snippet-pv-diag-500.S
> @@ -0,0 +1,39 @@
> +#include <asm/asm-offsets.h>
> +.section .text
> +
> +/* Clean and pre-load registers that are used for diag 500 */
> +xgr	%r1, %r1
> +xgr	%r2, %r2
> +xgr	%r3, %r3
> +xgr	%r4, %r4
> +lghi	%r1, 1
> +lghi	%r2, 2
> +lghi	%r3, 3
> +lghi	%r4, 4
> +
> +/* Let's jump to the next label on a PGM */
> +xgr	%r5, %r5
> +stg	%r5, GEN_LC_PGM_NEW_PSW
> +larl	%r5, next
> +stg	%r5, GEN_LC_PGM_NEW_PSW + 8
> +
> +/* Execute the diag500 */
> +diag	0, 0, 0x500
> +
> +/* Should never be executed because of the PGM */
> +diag	0, 0, 0x44
> +
> +/* Execute again to test spec PGM injection*/
> +next:
> +lh	%r1, GEN_LC_PGM_INT_CODE
> +diag	%r1, 0, 0x9c
> +larl	%r5, done
> +stg	%r5, GEN_LC_PGM_NEW_PSW + 8
> +diag	0, 0, 0x500
> +
> +/* Should never be executed because of the PGM */
> +diag	0, 0, 0x44
> +
> +done:
> +lh	%r1, GEN_LC_PGM_INT_CODE
> +diag	%r1, 0, 0x9c
> diff --git a/s390x/snippets/asm/snippet-pv-diag-yield.S b/s390x/snippets/asm/snippet-pv-diag-yield.S
> new file mode 100644
> index 00000000..5795cf0f
> --- /dev/null
> +++ b/s390x/snippets/asm/snippet-pv-diag-yield.S
> @@ -0,0 +1,7 @@
> +.section .text
> +
> +xgr	%r0, %r0
> +xgr	%r1, %r1
> +diag	0,0,0x44
> +lghi	%r1, 42
> +diag	1,0,0x9c