diff --git a/linux-user/strace.c b/linux-user/strace.c
index aad2b62ca416..669200c4a4c0 100644
--- a/linux-user/strace.c
+++ b/linux-user/strace.c
@@ -3999,6 +3999,25 @@ print_tgkill(CPUArchState *cpu_env, const struct syscallname *name,
 }
 #endif
 
+#if defined(TARGET_NR_pread64) || defined(TARGET_NR_pwrite64)
+static void
+print_pread64(CPUArchState *cpu_env, const struct syscallname *name,
+        abi_long arg0, abi_long arg1, abi_long arg2,
+        abi_long arg3, abi_long arg4, abi_long arg5)
+{
+    if (regpairs_aligned(cpu_env, TARGET_NR_pread64)) {
+        arg3 = arg4;
+        arg4 = arg5;
+    }
+    print_syscall_prologue(name);
+    print_raw_param("%d", arg0, 0);
+    print_pointer(arg1, 0);
+    print_raw_param("%d", arg2, 0);
+    print_raw_param("%" PRIu64, target_offset64(arg3, arg4), 1);
+    print_syscall_epilogue(name);
+}
+#endif
+
 #ifdef TARGET_NR_statx
 static void
 print_statx(CPUArchState *cpu_env, const struct syscallname *name,
diff --git a/linux-user/strace.list b/linux-user/strace.list
index c7808ea118f9..6655d4f26d66 100644
--- a/linux-user/strace.list
+++ b/linux-user/strace.list
@@ -1068,7 +1068,7 @@
 { TARGET_NR_prctl, "prctl" , NULL, NULL, NULL },
 #endif
 #ifdef TARGET_NR_pread64
-{ TARGET_NR_pread64, "pread64" , NULL, NULL, NULL },
+{ TARGET_NR_pread64, "pread64" , NULL, print_pread64, NULL },
 #endif
 #ifdef TARGET_NR_preadv
 { TARGET_NR_preadv, "preadv" , NULL, NULL, NULL },
@@ -1099,7 +1099,7 @@
 { TARGET_NR_putpmsg, "putpmsg" , NULL, NULL, NULL },
 #endif
 #ifdef TARGET_NR_pwrite64
-{ TARGET_NR_pwrite64, "pwrite64" , NULL, NULL, NULL },
+{ TARGET_NR_pwrite64, "pwrite64" , NULL, print_pread64, NULL },
 #endif
 #ifdef TARGET_NR_pwritev
 { TARGET_NR_pwritev, "pwritev" , NULL, NULL, NULL },
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 08162cc966e3..9b9e3bd5e374 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3440,7 +3440,17 @@ static abi_long do_accept4(int fd, abi_ulong target_addr,
     abi_long ret;
     int host_flags;
 
-    host_flags = target_to_host_bitmask(flags, fcntl_flags_tbl);
+    if (flags & ~(TARGET_SOCK_CLOEXEC | TARGET_SOCK_NONBLOCK)) {
+        return -TARGET_EINVAL;
+    }
+
+    host_flags = 0;
+    if (flags & TARGET_SOCK_NONBLOCK) {
+        host_flags |= SOCK_NONBLOCK;
+    }
+    if (flags & TARGET_SOCK_CLOEXEC) {
+        host_flags |= SOCK_CLOEXEC;
+    }
 
     if (target_addr == 0) {
         return get_errno(safe_accept4(fd, NULL, NULL, host_flags));
@@ -7132,6 +7142,10 @@ static abi_long do_fcntl(int fd, int cmd, abi_ulong arg)
         ret = get_errno(safe_fcntl(fd, host_cmd, arg));
         if (ret >= 0) {
             ret = host_to_target_bitmask(ret, fcntl_flags_tbl);
+            /* tell 32-bit guests it uses largefile on 64-bit hosts: */
+            if (O_LARGEFILE == 0 && HOST_LONG_BITS == 64) {
+                ret |= TARGET_O_LARGEFILE;
+            }
         }
         break;