On 29/06/2021 15.18, Janosch Frank wrote:
Let's also check the PEI values to make sure our VSIE implementation
is correct.
Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
---
s390x/Makefile | 2 +
s390x/mvpg-sie.c | 151 ++++++++++++++++++++++++++++++++
s390x/snippets/c/mvpg-snippet.c | 33 +++++++
s390x/unittests.cfg | 3 +
4 files changed, 189 insertions(+)
create mode 100644 s390x/mvpg-sie.c
create mode 100644 s390x/snippets/c/mvpg-snippet.c
diff --git a/s390x/Makefile b/s390x/Makefile
index ba32f4c..07af26d 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -23,6 +23,7 @@ tests += $(TEST_DIR)/sie.elf
tests += $(TEST_DIR)/mvpg.elf
tests += $(TEST_DIR)/uv-host.elf
tests += $(TEST_DIR)/edat.elf
+tests += $(TEST_DIR)/mvpg-sie.elf
tests_binary = $(patsubst %.elf,%.bin,$(tests))
ifneq ($(HOST_KEY_DOCUMENT),)
@@ -82,6 +83,7 @@ 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
$(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o $(FLATLIBS)
$(OBJCOPY) -O binary $(patsubst %.gbin,%.o,$@) $@
diff --git a/s390x/mvpg-sie.c b/s390x/mvpg-sie.c
new file mode 100644
index 0000000..3536c6a
--- /dev/null
+++ b/s390x/mvpg-sie.c
@@ -0,0 +1,151 @@
+#include <libcflat.h>
+#include <asm/asm-offsets.h>
+#include <asm-generic/barrier.h>
+#include <asm/pgtable.h>
+#include <mmu.h>
+#include <asm/page.h>
+#include <asm/facility.h>
+#include <asm/mem.h>
+#include <alloc_page.h>
+#include <vm.h>
+#include <sclp.h>
+#include <sie.h>
+
+static u8 *guest;
+static u8 *guest_instr;
+static struct vm vm;
+
+static uint8_t *src;
+static uint8_t *dst;
+static uint8_t *cmp;
+
+extern const char _binary_s390x_snippets_c_mvpg_snippet_gbin_start[];
+extern const char _binary_s390x_snippets_c_mvpg_snippet_gbin_end[];
+int binary_size;
+
+static void sie(struct vm *vm)
+{
+ /* Reset icptcode so we don't trip over it below */
+ vm->sblk->icptcode = 0;
+
+ while (vm->sblk->icptcode == 0) {
+ sie64a(vm->sblk, &vm->save_area);
+ if (vm->sblk->icptcode == ICPT_VALIDITY)
+ assert(0);
Please replace the above two lines with:
assert(vm->sblk->icptcode != ICPT_VALIDITY);
+ }
+ vm->save_area.guest.grs[14] = vm->sblk->gg14;
+ vm->save_area.guest.grs[15] = vm->sblk->gg15;
+}
+
+static void test_mvpg_pei(void)
+{
+ uint64_t **pei_dst = (uint64_t **)((uintptr_t) vm.sblk + 0xc0);
+ uint64_t **pei_src = (uint64_t **)((uintptr_t) vm.sblk + 0xc8);
+
+ report_prefix_push("pei");
+
+ report_prefix_push("src");
+ memset(dst, 0, PAGE_SIZE);
+ protect_page(src, PAGE_ENTRY_I);
+ sie(&vm);
+ report(vm.sblk->icptcode == ICPT_PARTEXEC, "Partial execution");
+ report((uintptr_t)**pei_src == (uintptr_t)src + PAGE_ENTRY_I, "PEI_SRC correct");
+ report((uintptr_t)**pei_dst == (uintptr_t)dst, "PEI_DST correct");
+ unprotect_page(src, PAGE_ENTRY_I);
+ report(!memcmp(cmp, dst, PAGE_SIZE), "Destination intact");
+ /*
+ * We need to execute the diag44 which is used as a blocker
+ * behind the mvpg. It makes sure we fail the tests above if
+ * the mvpg wouldn't have intercepted.
+ */
+ sie(&vm);
+ /* Make sure we intercepted for the diag44 and nothing else */
+ assert(vm.sblk->icptcode == ICPT_INST &&
+ vm.sblk->ipa == 0x8300 && vm.sblk->ipb == 0x440000);
+ report_prefix_pop();
+
+ /* Clear PEI data for next check */
+ report_prefix_push("dst");
+ memset((uint64_t *)((uintptr_t) vm.sblk + 0xc0), 0, 16);
+ memset(dst, 0, PAGE_SIZE);
+ protect_page(dst, PAGE_ENTRY_I);
+ sie(&vm);
+ report(vm.sblk->icptcode == ICPT_PARTEXEC, "Partial execution");
+ report((uintptr_t)**pei_src == (uintptr_t)src, "PEI_SRC correct");
+ report((uintptr_t)**pei_dst == (uintptr_t)dst + PAGE_ENTRY_I, "PEI_DST correct");
+ /* Needed for the memcmp and general cleanup */
+ unprotect_page(dst, PAGE_ENTRY_I);
+ report(!memcmp(cmp, dst, PAGE_SIZE), "Destination intact");
+ report_prefix_pop();
+
+ report_prefix_pop();
+}
Still quite a lot of magic values in above code ... any chance to introduce
some #defines finally?
+static void test_mvpg(void)
+{
+ int binary_size = ((uintptr_t)_binary_s390x_snippets_c_mvpg_snippet_gbin_end -
+ (uintptr_t)_binary_s390x_snippets_c_mvpg_snippet_gbin_start);
+
+ memcpy(guest, _binary_s390x_snippets_c_mvpg_snippet_gbin_start, binary_size);
+ memset(src, 0x42, PAGE_SIZE);
+ memset(dst, 0x43, PAGE_SIZE);
+ sie(&vm);
+ mb();
I think you don't need the mb() here.
+ report(!memcmp(src, dst, PAGE_SIZE) && *dst == 0x42, "Page moved");
+}
Thomas
