MIPS: VPE: Exit vpe_release() early if vpe_run() isn't defined

vpe_run() is a weak symbol.  If there's no definition of it, its value is
zero.

If vpe_run is zero, return failure early.  We're going to fail anyway, so
there's no point in getting a VPE and attempting to load it.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: linux-mips@linux-mips.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10683/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/vpe.c

@@ -821,13 +821,18 @@ static int vpe_release(struct inode *inode, struct file *filp)
 	Elf_Ehdr *hdr;
 	int ret = 0;
 
+	if (!vpe_run) {
+		pr_warn("VPE loader: ELF load failed.\n");
+		return -ENOEXEC;
+	}
+
 	v = get_vpe(aprp_cpu_index());
 	if (v == NULL)
 		return -ENODEV;
 
 	hdr = (Elf_Ehdr *) v->pbuffer;
 	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) == 0) {
-		if ((vpe_elfload(v) >= 0) && vpe_run) {
+		if (vpe_elfload(v) >= 0) {
 			vpe_run(v);
 		} else {
 			pr_warn("VPE loader: ELF load failed.\n");