powerpc: Fix interrupt range check on debug exception

We do not want to take single step and branch-taken debug exception
in kernel exception code. But the address range check was not covering
all kernel exception handlers address range.

With this patch we defined the interrupt_end label which defines the
end on kernel exception code. So now we check interrupt_base to
interrupt_end range for not handling debug exception in kernel
exception entry.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

3 files changed, 12 insertions, 8 deletions

diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S
index 7a2e5e421abf..97e2671cde7f 100644
--- a/arch/powerpc/kernel/head_44x.S
+++ b/arch/powerpc/kernel/head_44x.S
@@ -769,6 +769,8 @@ finish_tlb_load_47x:
          */
         DEBUG_CRIT_EXCEPTION
 
+interrupt_end:
+
 /*
  * Global functions
  */
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index b3853504498d..a620203f7de3 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -281,13 +281,13 @@ label:
         andis.  r10,r10,(DBSR_IC|DBSR_BT)@h;                                  \
         beq+    2f;                                                           \
                                                                               \
-        lis     r10,KERNELBASE@h;       /* check if exception in vectors */   \
-        ori     r10,r10,KERNELBASE@l;                                         \
+        lis     r10,interrupt_base@h;   /* check if exception in vectors */   \
+        ori     r10,r10,interrupt_base@l;                                     \
         cmplw   r12,r10;                                                      \
         blt+    2f;                     /* addr below exception vectors */    \
                                                                               \
-        lis     r10,DebugDebug@h;                                             \
-        ori     r10,r10,DebugDebug@l;                                         \
+        lis     r10,interrupt_end@h;                                          \
+        ori     r10,r10,interrupt_end@l;                                      \
         cmplw   r12,r10;                                                      \
         bgt+    2f;                     /* addr above exception vectors */    \
                                                                               \
@@ -334,13 +334,13 @@ label:
         andis.  r10,r10,(DBSR_IC|DBSR_BT)@h;                                  \
         beq+    2f;                                                           \
                                                                               \
-        lis     r10,KERNELBASE@h;       /* check if exception in vectors */   \
-        ori     r10,r10,KERNELBASE@l;                                         \
+        lis     r10,interrupt_base@h;   /* check if exception in vectors */   \
+        ori     r10,r10,interrupt_base@l;                                     \
         cmplw   r12,r10;                                                      \
         blt+    2f;                     /* addr below exception vectors */    \
                                                                               \
-        lis     r10,DebugCrit@h;                                              \
-        ori     r10,r10,DebugCrit@l;                                          \
+        lis     r10,interrupt_end@h;                                          \
+        ori     r10,r10,interrupt_end@l;                                      \
         cmplw   r12,r10;                                                      \
         bgt+    2f;                     /* addr above exception vectors */    \
                                                                               \
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 6f62a737f607..d10a7cacccd2 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -605,6 +605,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
         /* Embedded Hypervisor Privilege */
         EXCEPTION(0, HV_PRIV, Ehvpriv, unknown_exception, EXC_XFER_EE)
 
+interrupt_end:
+
 /*
  * Local functions
  */