diff --git a/lib/portability.c b/lib/portability.c
index 89744dd04..89ee78e91 100644
--- a/lib/portability.c
+++ b/lib/portability.c
@@ -623,42 +623,34 @@ int get_block_device_size(int fd, unsigned long long* size)
 }
 #endif
 
-static ssize_t copy_file_range_wrap(int infd, off_t *inoff, int outfd,
-    off_t *outoff, size_t len, unsigned flags)
-{
-  // glibc added this constant in git at the end of 2017, shipped in 2018-02.
-#if defined(__NR_copy_file_range)
-  return syscall(__NR_copy_file_range, infd, inoff, outfd, outoff, len, flags);
-#else
-  errno = EINVAL;
-  return -1;
-#endif
-}
-
 // Return bytes copied from in to out. If bytes <0 copy all of in to out.
 // If consumed isn't null, amount read saved there (return is written or error)
 long long sendfile_len(int in, int out, long long bytes, long long *consumed)
 {
   long long total = 0, len, ww;
-  int copy_file_range = CFG_TOYBOX_COPYFILERANGE;
+  int try_cfr = 1;
 
   if (consumed) *consumed = 0;
-  if (in<0) return 0;
-  while (bytes != total) {
+  if (in>=0) while (bytes != total) {
     ww = 0;
     len = bytes-total;
 
     errno = 0;
-    if (copy_file_range) {
+    if (try_cfr) {
       if (bytes<0 || bytes>(1<<30)) len = (1<<30);
-      len = copy_file_range_wrap(in, 0, out, 0, len, 0);
+      // glibc added this constant in git at the end of 2017, shipped 2018-02.
+#if defined (__NR_copy_file_range)
+      len = syscall(__NR_copy_file_range, in, 0, out, 0, len, 0);
+#else
+      errno = EINVAL;
+      len = -1;
+#endif
       if (len < 0 && errno == EINVAL) {
-        copy_file_range = 0;
+        try_cfr = 0;
 
         continue;
       }
-    }
-    if (!copy_file_range) {
+    } else {
       if (bytes<0 || len>sizeof(libbuf)) len = sizeof(libbuf);
       ww = len = read(in, libbuf, len);
     }
diff --git a/scripts/genconfig.sh b/scripts/genconfig.sh
index af87c6596..f2be86534 100755
--- a/scripts/genconfig.sh
+++ b/scripts/genconfig.sh
@@ -100,13 +100,6 @@ EOF
     int main(void) { char buf[100]; getrandom(buf, 100, 0); }
 EOF
 
-  # glibc requires #define GNU to get the wrapper for this Linux system call,
-  # so just use syscall().
-  probesymbol TOYBOX_COPYFILERANGE << EOF
-    #include <sys/syscall.h>
-    #include <unistd.h>
-    int main(void) { syscall(__NR_copy_file_range, 0, 0, 1, 0, 123, 0); }
-EOF
   probesymbol TOYBOX_HASTIMERS << EOF
     #include <signal.h>
     #include <time.h>