1 files changed, 29 insertions, 0 deletions

diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index 970e3e96b1d0..26e1a7e78d13 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -406,3 +406,32 @@ asmlinkage void bad_stack(void)
 {
         do_exit(SIGSEGV);
 }
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+        register unsigned long __a0 asm("$4") = (unsigned long) filename;
+        register unsigned long __a1 asm("$5") = (unsigned long) argv;
+        register unsigned long __a2 asm("$6") = (unsigned long) envp;
+        register unsigned long __a3 asm("$7");
+        unsigned long __v0;
+
+        __asm__ volatile ("                                     \n"
+        "       .set    noreorder                               \n"
+        "       li      $2, %5          # __NR_execve           \n"
+        "       syscall                                         \n"
+        "       move    %0, $2                                  \n"
+        "       .set    reorder                                 \n"
+        : "=&r" (__v0), "=r" (__a3)
+        : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
+        : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
+          "memory");
+
+        if (__a3 == 0)
+                return __v0;
+
+        return -__v0;
+}