1 files changed, 3 insertions, 1 deletions

diff --git a/firmware/crt0.S b/firmware/crt0.S
index e7210e6d78..e8ccede187 100644
--- a/firmware/crt0.S
+++ b/firmware/crt0.S
@@ -291,9 +291,11 @@ boot_table:
     ldr    r12, =0x70002800 /* IISCONFIG */
     ldr    r11, =p
 #endif
-    /* Let abort mode use IRQ stack */
+    /* Let abort and undefined modes use IRQ stack */
     msr    cpsr_c, #0xd7
     ldr    sp, =irq_stack
+    msr    cpsr_c, #0xdb
+    ldr    sp, =irq_stack
     /* Switch to supervisor mode */
     msr    cpsr_c, #0xd3
     ldr    sp, =stackend