3 files changed, 22 insertions, 2 deletions

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 2d35d83961b2..e4732459c485 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -752,6 +752,17 @@ int get_endian(struct task_struct *tsk, unsigned long adr)
         return put_user(val, (unsigned int __user *)adr);
 }
 
+int set_unalign_ctl(struct task_struct *tsk, unsigned int val)
+{
+        tsk->thread.align_ctl = val;
+        return 0;
+}
+
+int get_unalign_ctl(struct task_struct *tsk, unsigned long adr)
+{
+        return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr);
+}
+
 #define TRUNC_PTR(x)    ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
 
 int sys_clone(unsigned long clone_flags, unsigned long usp,
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 03def5715494..91a6e04d9741 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -805,9 +805,11 @@ void __kprobes program_check_exception(struct pt_regs *regs)
 
 void alignment_exception(struct pt_regs *regs)
 {
-        int fixed;
+        int fixed = 0;
 
-        fixed = fix_alignment(regs);
+        /* we don't implement logging of alignment exceptions */
+        if (!(current->thread.align_ctl & PR_UNALIGN_SIGBUS))
+                fixed = fix_alignment(regs);
 
         if (fixed == 1) {
                 regs->nip += 4; /* skip over emulated instruction */
diff --git a/include/asm-powerpc/processor.h b/include/asm-powerpc/processor.h
index fa6163268153..d2c2c95f913b 100644
--- a/include/asm-powerpc/processor.h
+++ b/include/asm-powerpc/processor.h
@@ -149,6 +149,7 @@ struct thread_struct {
                 unsigned int val;       /* Floating point status */
         } fpscr;
         int             fpexc_mode;     /* floating-point exception mode */
+        unsigned int    align_ctl;      /* alignment handling control */
 #ifdef CONFIG_PPC64
         unsigned long   start_tb;       /* Start purr when proc switched in */
         unsigned long   accum_tb;       /* Total accumilated purr for process */
@@ -217,6 +218,12 @@ extern int set_fpexc_mode(struct task_struct *tsk, unsigned int val);
 extern int get_endian(struct task_struct *tsk, unsigned long adr);
 extern int set_endian(struct task_struct *tsk, unsigned int val);
 
+#define GET_UNALIGN_CTL(tsk, adr)       get_unalign_ctl((tsk), (adr))
+#define SET_UNALIGN_CTL(tsk, val)       set_unalign_ctl((tsk), (val))
+
+extern int get_unalign_ctl(struct task_struct *tsk, unsigned long adr);
+extern int set_unalign_ctl(struct task_struct *tsk, unsigned int val);
+
 static inline unsigned int __unpack_fe01(unsigned long msr_bits)
 {
         return ((msr_bits & MSR_FE0) >> 10) | ((msr_bits & MSR_FE1) >> 8);