Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus

* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus: (46 commits)
  ftrace/MIPS: Enable C Version of recordmcount
  ftrace/MIPS: Add module support for C version of recordmcount
  ftrace/MIPS: Add MIPS64 support for C version of recordmcount
  MIPS: Make TASK_SIZE reflect proper size for both 32 and 64 bit processes.
  MIPS: Allow UserLocal on MIPS_R1 processors
  MIPS: Honor L2 bypass bit
  MIPS: Add BMIPS CP0 register definitions
  MIPS: Add BMIPS processor types to Kconfig
  MIPS: Decouple BMIPS CPU support from bcm47xx/bcm63xx SoC code
  MIPS: Add support for hardware performance events (mipsxx)
  MIPS: Perf-events: Add callchain support
  MIPS: add support for hardware performance events (skeleton)
  MIPS: add support for software performance events
  MIPS: define local_xchg from xchg_local to atomic_long_xchg
  MIPS: AR7: Add support for Titan (TNETV10xx) SoC variant
  MIPS: AR7: Initialize GPIO earlier
  MIPS: Add platform device and Kconfig for Octeon USB EHCI / OHCI
  USB: Add EHCI and OHCH glue for OCTEON II SOCs.
  MIPS: Octeon: Add register definitions for EHCI / OHCI USB glue logic.
  MIPS: Octeon: Apply CN63XXP1 errata workarounds.
  ...

1 files changed, 24 insertions, 0 deletions

diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
index c6345f579a8a..4f93db58a79e 100644
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c
@@ -151,6 +151,29 @@ void __init init_IRQ(void)
 #endif
 }
 
+#ifdef DEBUG_STACKOVERFLOW
+static inline void check_stack_overflow(void)
+{
+        unsigned long sp;
+
+        __asm__ __volatile__("move %0, $sp" : "=r" (sp));
+        sp &= THREAD_MASK;
+
+        /*
+         * Check for stack overflow: is there less than STACK_WARN free?
+         * STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
+         */
+        if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
+                printk("do_IRQ: stack overflow: %ld\n",
+                       sp - sizeof(struct thread_info));
+                dump_stack();
+        }
+}
+#else
+static inline void check_stack_overflow(void) {}
+#endif
+
+
 /*
  * do_IRQ handles all normal device IRQ's (the special
  * SMP cross-CPU interrupts have their own specific
@@ -159,6 +182,7 @@ void __init init_IRQ(void)
 void __irq_entry do_IRQ(unsigned int irq)
 {
         irq_enter();
+        check_stack_overflow();
         __DO_IRQ_SMTC_HOOK(irq);
         generic_handle_irq(irq);
         irq_exit();