From: David Hildenbrand <david@redhat.com>
To: qemu-devel@nongnu.org
Cc: "Thomas Huth" <thuth@redhat.com>,
"David Hildenbrand" <david@redhat.com>,
"Cornelia Huck" <cohuck@redhat.com>,
qemu-s390x@nongnu.org, "Alex Bennée" <alex.bennee@linaro.org>,
"Richard Henderson" <rth@twiddle.net>
Subject: [Qemu-devel] [PATCH v1] tests/tcg: target/s390x: Test MVC
Date: Thu, 19 Sep 2019 11:28:29 +0200 [thread overview]
Message-ID: <20190919092829.15393-1-david@redhat.com> (raw)
Let's add a test that especially verifies that no data will be touched
in case we cross page boundaries and one page access triggers a fault.
Before the fault-safe handling fixes, the test failes with:
TEST mvc on s390x
data modified during a fault
make[2]: *** [../Makefile.target:116: run-mvc] Error 1
Cc: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
tests/tcg/s390x/Makefile.target | 1 +
tests/tcg/s390x/mvc.c | 109 ++++++++++++++++++++++++++++++++
2 files changed, 110 insertions(+)
create mode 100644 tests/tcg/s390x/mvc.c
diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
index 6a3bfa8b29..241ef28f61 100644
--- a/tests/tcg/s390x/Makefile.target
+++ b/tests/tcg/s390x/Makefile.target
@@ -7,3 +7,4 @@ TESTS+=exrl-trt
TESTS+=exrl-trtr
TESTS+=pack
TESTS+=mvo
+TESTS+=mvc
diff --git a/tests/tcg/s390x/mvc.c b/tests/tcg/s390x/mvc.c
new file mode 100644
index 0000000000..aa552d52e5
--- /dev/null
+++ b/tests/tcg/s390x/mvc.c
@@ -0,0 +1,109 @@
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <signal.h>
+#include <setjmp.h>
+
+jmp_buf jmp_env;
+
+static void handle_sigsegv(int sig)
+{
+ siglongjmp(jmp_env, 1);
+}
+
+#define ALLOC_SIZE (2 * 4096)
+
+static inline void mvc_256(const char *dst, const char *src)
+{
+ asm volatile (
+ " mvc 0(256,%[dst]),0(%[src])\n"
+ :
+ : [dst] "d" (dst),
+ [src] "d" (src)
+ : "memory");
+}
+
+int main(void)
+{
+ char *src, *dst;
+ int i;
+
+ /* register the SIGSEGV handler */
+ if (signal(SIGSEGV, handle_sigsegv) == SIG_ERR) {
+ fprintf(stderr, "SIGSEGV not registered\n");
+ return 1;
+ }
+
+ /* prepare the buffers - two consecutive pages */
+ src = valloc(ALLOC_SIZE);
+ dst = valloc(ALLOC_SIZE);
+ memset(src, 0xff, ALLOC_SIZE);
+ memset(dst, 0x0, ALLOC_SIZE);
+
+ /* protect the second pages */
+ if (mprotect(src + 4096, 4096, PROT_NONE) ||
+ mprotect(dst + 4096, 4096, PROT_NONE)) {
+ fprintf(stderr, "mprotect failed\n");
+ return 1;
+ }
+
+ /* fault on second destination page */
+ if (sigsetjmp(jmp_env, 1) == 0) {
+ mvc_256(dst + 4096 - 128, src);
+ fprintf(stderr, "fault not triggered\n");
+ return 1;
+ }
+
+ /* fault on second source page */
+ if (sigsetjmp(jmp_env, 1) == 0) {
+ mvc_256(dst, src + 4096 - 128);
+ fprintf(stderr, "fault not triggered\n");
+ return 1;
+ }
+
+ /* fault on second source and second destination page */
+ if (sigsetjmp(jmp_env, 1) == 0) {
+ mvc_256(dst + 4096 - 128, src + 4096 - 128);
+ fprintf(stderr, "fault not triggered\n");
+ return 1;
+ }
+
+ /* restore permissions */
+ if (mprotect(src + 4096, 4096, PROT_READ | PROT_WRITE) ||
+ mprotect(dst + 4096, 4096, PROT_READ | PROT_WRITE)) {
+ fprintf(stderr, "mprotect failed\n");
+ return 1;
+ }
+
+ /* no data must be touched during the faults */
+ for (i = 0; i < ALLOC_SIZE; i++) {
+ if (src[i] != 0xff || dst[i]) {
+ fprintf(stderr, "data modified during a fault\n");
+ return 1;
+ }
+ }
+
+ /* test if MVC works now correctly accross page boundaries */
+ mvc_256(dst + 4096 - 128, src + 4096 - 128);
+ for (i = 0; i < ALLOC_SIZE; i++) {
+ if (src[i] != 0xff) {
+ fprintf(stderr, "src modified\n");
+ return 1;
+ }
+ if (i < 4096 - 128 || i >= 4096 + 128) {
+ if (dst[i]) {
+ fprintf(stderr, "wrong dst modified\n");
+ return 1;
+ }
+ } else {
+ if (dst[i] != 0xff) {
+ fprintf(stderr, "wrong data moved\n");
+ return 1;
+ }
+ }
+ }
+
+ return 0;
+}
--
2.21.0
next reply other threads:[~2019-09-19 9:29 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-19 9:28 David Hildenbrand [this message]
2019-09-19 9:41 ` [Qemu-devel] [PATCH v1] tests/tcg: target/s390x: Test MVC David Hildenbrand
2019-09-19 16:01 ` Richard Henderson
2019-09-20 9:14 ` David Hildenbrand
2019-09-20 12:03 ` David Hildenbrand
2019-09-20 13:02 ` Alex Bennée
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