On 05/10/2021 11.11, Janis Schoetterl-Glausch wrote:
Check that specification exceptions cause intercepts when
specification exception interpretation is off.
Check that specification exceptions caused by program new PSWs
cause interceptions.
We cannot assert that non program new PSW specification exceptions
are interpreted because whether interpretation occurs or not is
configuration dependent.
Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
---
s390x/Makefile | 2 +
lib/s390x/sie.h | 1 +
s390x/snippets/c/spec_ex.c | 20 +++++++++
s390x/spec_ex-sie.c | 83 ++++++++++++++++++++++++++++++++++++++
s390x/unittests.cfg | 3 ++
5 files changed, 109 insertions(+)
create mode 100644 s390x/snippets/c/spec_ex.c
create mode 100644 s390x/spec_ex-sie.c
diff --git a/s390x/Makefile b/s390x/Makefile
index ef8041a..7198882 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -24,6 +24,7 @@ tests += $(TEST_DIR)/mvpg.elf
tests += $(TEST_DIR)/uv-host.elf
tests += $(TEST_DIR)/edat.elf
tests += $(TEST_DIR)/mvpg-sie.elf
+tests += $(TEST_DIR)/spec_ex-sie.elf
tests_binary = $(patsubst %.elf,%.bin,$(tests))
ifneq ($(HOST_KEY_DOCUMENT),)
@@ -85,6 +86,7 @@ snippet_asmlib = $(SNIPPET_DIR)/c/cstart.o
# perquisites (=guests) for the snippet hosts.
# $(TEST_DIR)/<snippet-host>.elf: snippets = $(SNIPPET_DIR)/<c/asm>/<snippet>.gbin
$(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
$(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o $(FLATLIBS)
$(OBJCOPY) -O binary $(patsubst %.gbin,%.o,$@) $@
diff --git a/lib/s390x/sie.h b/lib/s390x/sie.h
index ca514ef..7ef7251 100644
--- a/lib/s390x/sie.h
+++ b/lib/s390x/sie.h
@@ -98,6 +98,7 @@ struct kvm_s390_sie_block {
uint8_t fpf; /* 0x0060 */
#define ECB_GS 0x40
#define ECB_TE 0x10
+#define ECB_SPECI 0x08
#define ECB_SRSI 0x04
#define ECB_HOSTPROTINT 0x02
uint8_t ecb; /* 0x0061 */
diff --git a/s390x/snippets/c/spec_ex.c b/s390x/snippets/c/spec_ex.c
new file mode 100644
index 0000000..bdba4f4
--- /dev/null
+++ b/s390x/snippets/c/spec_ex.c
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * © Copyright IBM Corp. 2021
+ *
+ * Snippet used by specification exception interception test.
+ */
+#include <stdint.h>
+#include <asm/arch_def.h>
+
+__attribute__((section(".text"))) int main(void)
+{
+ struct lowcore *lowcore = (struct lowcore *) 0;
+ uint64_t bad_psw = 0;
+
+ /* PSW bit 12 has no name or meaning and must be 0 */
+ lowcore->pgm_new_psw.mask = 1UL << (63 - 12);
+ lowcore->pgm_new_psw.addr = 0xdeadbeee;
+ asm volatile ("lpsw %0" :: "Q"(bad_psw));
+ return 0;
+}
diff --git a/s390x/spec_ex-sie.c b/s390x/spec_ex-sie.c
new file mode 100644
index 0000000..b7e79de
--- /dev/null
+++ b/s390x/spec_ex-sie.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * © Copyright IBM Corp. 2021
+ *
+ * Specification exception interception test.
+ * Checks that specification exception interceptions occur as expected when
+ * specification exception interpretation is off/on.
+ */
+#include <libcflat.h>
+#include <sclp.h>
+#include <asm/page.h>
+#include <asm/arch_def.h>
+#include <alloc_page.h>
+#include <vm.h>
+#include <sie.h>
+
+static struct vm vm;
+extern const char _binary_s390x_snippets_c_spec_ex_gbin_start[];
+extern const char _binary_s390x_snippets_c_spec_ex_gbin_end[];
+
+static void setup_guest(void)
+{
+ char *guest;
+ int binary_size = ((uintptr_t)_binary_s390x_snippets_c_spec_ex_gbin_end -
+ (uintptr_t)_binary_s390x_snippets_c_spec_ex_gbin_start);
+
+ setup_vm();
+ guest = alloc_pages(8);
+ memcpy(guest, _binary_s390x_snippets_c_spec_ex_gbin_start, binary_size);
+ sie_guest_create(&vm, (uint64_t) guest, HPAGE_SIZE);
+}
+
+static void reset_guest(void)
+{
+ vm.sblk->gpsw.addr = PAGE_SIZE * 4;
Could we please get a #define for this magic PAGE_SIZE * 4 value, with a
comment mentioning that the value comes from s390x/snippets/c/flat.lds ?
I know it's already like this in the mvpg-sie.c test, so this could also be
done in a follow-up patch instead, to fix mvpg-sie.c, too.
By the way, Janosch, do you remember why it s PAGE_SIZE * 4 and not
PAGE_SIZE * 2 ? Space for additional SMP lowcores?
+ vm.sblk->gpsw.mask = PSW_MASK_64;
+ vm.sblk->icptcode = 0;
+}
+
+static void test_spec_ex_sie(void)
+{
+ setup_guest();
+
+ report_prefix_push("SIE spec ex interpretation");
+ report_prefix_push("off");
+ reset_guest();
+ sie(&vm);
+ /* interpretation off -> initial exception must cause interception */
+ report(vm.sblk->icptcode == ICPT_PROGI
+ && vm.sblk->iprcc == PGM_INT_CODE_SPECIFICATION
+ && vm.sblk->gpsw.addr != 0xdeadbeee,
+ "Received specification exception intercept for initial exception");
+ report_prefix_pop();
+
+ report_prefix_push("on");
+ vm.sblk->ecb |= ECB_SPECI;
+ reset_guest();
+ sie(&vm);
+ /* interpretation on -> configuration dependent if initial exception causes
+ * interception, but invalid new program PSW must
+ */
+ report(vm.sblk->icptcode == ICPT_PROGI
+ && vm.sblk->iprcc == PGM_INT_CODE_SPECIFICATION,
+ "Received specification exception intercept");
+ if (vm.sblk->gpsw.addr == 0xdeadbeee)
+ report_info("Interpreted initial exception, intercepted invalid program new PSW exception");
+ else
+ report_info("Did not interpret initial exception");
+ report_prefix_pop();
+ report_prefix_pop();
+}
+
+int main(int argc, char **argv)
+{
+ if (!sclp_facilities.has_sief2) {
+ report_skip("SIEF2 facility unavailable");
+ goto out;
+ }
+
+ test_spec_ex_sie();
+out:
+ return report_summary();
+}
diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
index 9e1802f..3b454b7 100644
--- a/s390x/unittests.cfg
+++ b/s390x/unittests.cfg
@@ -109,3 +109,6 @@ file = edat.elf
[mvpg-sie]
file = mvpg-sie.elf
+
+[spec_ex-sie]
+file = spec_ex-sie.elf
Reviewed-by: Thomas Huth <thuth@xxxxxxxxxx>
