Subject: Re: [RFC PATCH] powerpc: Wire up three syscalls

From: Pranith Kumar <[email-masked]>
Date: Sun, 31 Aug 2014 13:51:12 -0400

On 08/31/2014 10:34 AM, David Herrmann wrote:
> The only arch-dependent code for memfd_test.c is the syscall invocation:
>     memfd_create(const char *name, unsigned int flags);
> via glibc as:
>     syscall(__NR_memfd_create, name, flags);
>
> Can you debug your test-run (maybe via simple printk() in mm/shmem.c
> memfd_create()) and see what's going wrong there?
>
Hi David,

I figured out the problem. I am on a 32-bit system and using u64 for flags in fcntl() is the cause of the problem. Will you accept a patch making the test work on 32-bit systems as below?

Thanks!
--
Pranith

From: Pranith Kumar <[email-masked]>
Date: Sun, 31 Aug 2014 13:38:07 -0400
Subject: [PATCH] memfd_test: Make it work on 32-bit systems

This test currently fails on 32-bit systems since we use u64 type to pass the
flags to fcntl.

This commit changes this to use u32 type for flags to fcntl making it work on
32-bit systems.

Signed-off-by: Pranith Kumar <[email-masked]>
---
 tools/testing/selftests/memfd/memfd_test.c | 32 +++++++++++++++---------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/tools/testing/selftests/memfd/memfd_test.c b/tools/testing/selftests/memfd/memfd_test.c
index 3634c90..77e56ff 100644
--- a/tools/testing/selftests/memfd/memfd_test.c
+++ b/tools/testing/selftests/memfd/memfd_test.c
@@ -59,9 +59,9 @@ static void mfd_fail_new(const char *name, unsigned int flags)
     }
 }
 
-static __u64 mfd_assert_get_seals(int fd)
+static __u32 mfd_assert_get_seals(int fd)
 {
-    long r;
+    int r;
 
     r = fcntl(fd, F_GET_SEALS);
     if (r < 0) {
@@ -72,36 +72,36 @@ static __u64 mfd_assert_get_seals(int fd)
     return r;
 }
 
-static void mfd_assert_has_seals(int fd, __u64 seals)
+static void mfd_assert_has_seals(int fd, __u32 seals)
 {
-    __u64 s;
+    __u32 s;
 
     s = mfd_assert_get_seals(fd);
     if (s != seals) {
-        printf("%llu != %llu = GET_SEALS(%d)\n",
-               (unsigned long long)seals, (unsigned long long)s, fd);
+        printf("%lu != %lu = GET_SEALS(%d)\n",
+               (unsigned long)seals, (unsigned long)s, fd);
         abort();
     }
 }
 
-static void mfd_assert_add_seals(int fd, __u64 seals)
+static void mfd_assert_add_seals(int fd, __u32 seals)
 {
-    long r;
-    __u64 s;
+    int r;
+    __u32 s;
 
     s = mfd_assert_get_seals(fd);
     r = fcntl(fd, F_ADD_SEALS, seals);
     if (r < 0) {
-        printf("ADD_SEALS(%d, %llu -> %llu) failed: %m\n",
-               fd, (unsigned long long)s, (unsigned long long)seals);
+        printf("ADD_SEALS(%d, %lu -> %lu) failed: %m\n",
+               fd, (unsigned long)s, (unsigned long)seals);
         abort();
     }
 }
 
-static void mfd_fail_add_seals(int fd, __u64 seals)
+static void mfd_fail_add_seals(int fd, __u32 seals)
 {
-    long r;
-    __u64 s;
+    int r;
+    __u32 s;
 
     r = fcntl(fd, F_GET_SEALS);
     if (r < 0)
@@ -111,8 +111,8 @@ static void mfd_fail_add_seals(int fd, __u64 seals)
 
     r = fcntl(fd, F_ADD_SEALS, seals);
     if (r >= 0) {
-        printf("ADD_SEALS(%d, %llu -> %llu) didn't fail as expected\n",
-               fd, (unsigned long long)s, (unsigned long long)seals);
+        printf("ADD_SEALS(%d, %lu -> %lu) didn't fail as expected\n",
+               fd, (unsigned long)s, (unsigned long)seals);
         abort();
     }
 }
-- 
2.1.0