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[Qemu-devel] [PATCH v1] tests/tcg: target/s390x: Test MVC

David Hildenbrand posted 1 patch 4 years, 7 months ago
Failed in applying to current master (apply log)
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
[Qemu-devel] [PATCH v1] tests/tcg: target/s390x: Test MVC
Posted by David Hildenbrand 4 years, 7 months ago 
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
Re: [PATCH v1] tests/tcg: target/s390x: Test MVC
Posted by David Hildenbrand 4 years, 7 months ago 
On 19.09.19 11:28, David Hildenbrand wrote:
> 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;
> +}
> 

I'll send this along with the updated pull request of

"[PULL SUBSYSTEM s390x 00/29] s390x/tcg: mem_helper: Fault-safe handling"

-- 

Thanks,

David / dhildenb
Re: [PATCH v1] tests/tcg: target/s390x: Test MVC
Posted by Alex Bennée 4 years, 7 months ago 
David Hildenbrand <david@redhat.com> writes:

> On 19.09.19 11:28, David Hildenbrand wrote:
>> 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;
>> +}
>>
>
> I'll send this along with the updated pull request of
>
> "[PULL SUBSYSTEM s390x 00/29] s390x/tcg: mem_helper: Fault-safe
> handling"

Acked-by: Alex Bennée <alex.bennee@linaro.org>


--
Alex Bennée
Re: [Qemu-devel] [PATCH v1] tests/tcg: target/s390x: Test MVC
Posted by David Hildenbrand 4 years, 7 months ago 
On 19.09.19 11:28, David Hildenbrand wrote:
> 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);

If anybody cares, I can convert the obsolete valloc into a
posix_memalign(&src, 4096, ALLOC_SIZE) etc.

> +    memset(src, 0xff, ALLOC_SIZE);
> +    memset(dst, 0x0, ALLOC_SIZE);
> +


-- 

Thanks,

David / dhildenb
Re: [Qemu-devel] [PATCH v1] tests/tcg: target/s390x: Test MVC
Posted by Richard Henderson 4 years, 7 months ago 
On 9/19/19 2:41 AM, David Hildenbrand wrote:
>> +    /* prepare the buffers - two consecutive pages */
>> +    src = valloc(ALLOC_SIZE);
>> +    dst = valloc(ALLOC_SIZE);
> 
> If anybody cares, I can convert the obsolete valloc into a
> posix_memalign(&src, 4096, ALLOC_SIZE) etc.

I don't care.  It may be obsolete, but it still works.

If you were to change it to anything I would think mmap
instead of using mprotect on the heap at all...

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~
Re: [Qemu-devel] [PATCH v1] tests/tcg: target/s390x: Test MVC
Posted by David Hildenbrand 4 years, 7 months ago 
On 19.09.19 18:01, Richard Henderson wrote:
> On 9/19/19 2:41 AM, David Hildenbrand wrote:
>>> +    /* prepare the buffers - two consecutive pages */
>>> +    src = valloc(ALLOC_SIZE);
>>> +    dst = valloc(ALLOC_SIZE);
>>
>> If anybody cares, I can convert the obsolete valloc into a
>> posix_memalign(&src, 4096, ALLOC_SIZE) etc.
> 
> I don't care.  It may be obsolete, but it still works.
> 
> If you were to change it to anything I would think mmap
> instead of using mprotect on the heap at all...

Yeah, that was my other thought, but after all I own "full" pages.

I'll leave it like this than unless somebody objects :)

> 
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Thanks!

> 
> 
> r~
> 


-- 

Thanks,

David / dhildenb

Patchew 2.1-devel-0870f84

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