1 files changed, 51 insertions, 0 deletions

diff --git a/arch/um/sys-x86/stub_32.S b/arch/um/sys-x86/stub_32.S
new file mode 100644
index 000000000000..54a36ec20cb7
--- /dev/null
+++ b/arch/um/sys-x86/stub_32.S
@@ -0,0 +1,51 @@
+#include "as-layout.h"
+
+        .globl syscall_stub
+.section .__syscall_stub, "ax"
+
+        .globl batch_syscall_stub
+batch_syscall_stub:
+        /* load pointer to first operation */
+        mov     $(STUB_DATA+8), %esp
+
+again:
+        /* load length of additional data */
+        mov     0x0(%esp), %eax
+
+        /* if(length == 0) : end of list */
+        /* write possible 0 to header */
+        mov     %eax, STUB_DATA+4
+        cmpl    $0, %eax
+        jz      done
+
+        /* save current pointer */
+        mov     %esp, STUB_DATA+4
+
+        /* skip additional data */
+        add     %eax, %esp
+
+        /* load syscall-# */
+        pop     %eax
+
+        /* load syscall params */
+        pop     %ebx
+        pop     %ecx
+        pop     %edx
+        pop     %esi
+        pop     %edi
+        pop     %ebp
+
+        /* execute syscall */
+        int     $0x80
+
+        /* check return value */
+        pop     %ebx
+        cmp     %ebx, %eax
+        je      again
+
+done:
+        /* save return value */
+        mov     %eax, STUB_DATA
+
+        /* stop */
+        int3