sh: Set up correct siginfo structures for page faults.

Remove the previous saving of fault codes into the thread_struct
as they are never used, and appeared to be inherited from x86.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 40 insertions, 34 deletions

diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c
index b52037bc1255..0ee298079d82 100644
--- a/arch/sh/kernel/traps.c
+++ b/arch/sh/kernel/traps.c
@@ -93,7 +93,7 @@ void die(const char * str, struct pt_regs * regs, long err)
 
         if (!user_mode(regs) || in_interrupt())
                 dump_mem("Stack: ", regs->regs[15], THREAD_SIZE +
-                         (unsigned long)task_stack_page(current));
+                         (unsigned long)task_stack_page(current));
 
         bust_spinlocks(0);
         spin_unlock_irq(&die_lock);
@@ -201,7 +201,7 @@ static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
                 if (copy_to_user(dst,src,4))
                         goto fetch_fault;
                 ret = 0;
-                break;
+                break;
 
         case 2: /* mov.[bwl] to memory, possibly with pre-decrement */
                 if (instruction & 4)
@@ -225,7 +225,7 @@ static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
                 if (copy_from_user(dst,src,4))
                         goto fetch_fault;
                 ret = 0;
-                break;
+                break;
 
         case 6: /* mov.[bwl] from memory, possibly with post-increment */
                 src = (unsigned char*) *rm;
@@ -233,7 +233,7 @@ static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
                         *rm += count;
                 dst = (unsigned char*) rn;
                 *(unsigned long*)dst = 0;
-                
+
 #ifdef __LITTLE_ENDIAN__
                 if (copy_from_user(dst, src, count))
                         goto fetch_fault;
@@ -244,7 +244,7 @@ static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
                 }
 #else
                 dst += 4-count;
-                
+
                 if (copy_from_user(dst, src, count))
                         goto fetch_fault;
 
@@ -323,7 +323,8 @@ static inline int handle_unaligned_delayslot(struct pt_regs *regs)
                         return -EFAULT;
 
                 /* kernel */
-                die("delay-slot-insn faulting in handle_unaligned_delayslot", regs, 0);
+                die("delay-slot-insn faulting in handle_unaligned_delayslot",
+                    regs, 0);
         }
 
         return handle_unaligned_ins(instruction,regs);
@@ -364,7 +365,8 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
         if (user_mode(regs) && handle_unaligned_notify_count>0) {
                 handle_unaligned_notify_count--;
 
-                printk("Fixing up unaligned userspace access in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
+                printk(KERN_NOTICE "Fixing up unaligned userspace access "
+                       "in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
                        current->comm,current->pid,(u16*)regs->pc,instruction);
         }
 
@@ -499,7 +501,15 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
 #endif
 
 /*
- * Handle various address error exceptions
+ * Handle various address error exceptions:
+ *  - instruction address error:
+ *       misaligned PC
+ *       PC >= 0x80000000 in user mode
+ *  - data address error (read and write)
+ *       misaligned data access
+ *       access to >= 0x80000000 is user mode
+ * Unfortuntaly we can't distinguish between instruction address error
+ * and data address errors caused by read acceses.
  */
 asmlinkage void do_address_error(struct pt_regs *regs,
                                  unsigned long writeaccess,
@@ -507,6 +517,7 @@ asmlinkage void do_address_error(struct pt_regs *regs,
 {
         unsigned long error_code = 0;
         mm_segment_t oldfs;
+        siginfo_t info;
 #ifndef CONFIG_CPU_SH2A
         u16 instruction;
         int tmp;
@@ -520,22 +531,15 @@ asmlinkage void do_address_error(struct pt_regs *regs,
         oldfs = get_fs();
 
         if (user_mode(regs)) {
+                int si_code = BUS_ADRERR;
+
                 local_irq_enable();
-                current->thread.error_code = error_code;
-#ifdef CONFIG_CPU_SH2
-                /*
-                 * On the SH-2, we only have a single vector for address
-                 * errors, there's no differentiating between a load error
-                 * and a store error.
-                 */
-                current->thread.trap_no = 9;
-#else
-                current->thread.trap_no = (writeaccess) ? 8 : 7;
-#endif
 
                 /* bad PC is not something we can fix */
-                if (regs->pc & 1)
+                if (regs->pc & 1) {
+                        si_code = BUS_ADRALN;
                         goto uspace_segv;
+                }
 
 #ifndef CONFIG_CPU_SH2A
                 set_fs(USER_DS);
@@ -554,9 +558,16 @@ asmlinkage void do_address_error(struct pt_regs *regs,
                         return; /* sorted */
 #endif
 
-        uspace_segv:
-                printk(KERN_NOTICE "Killing process \"%s\" due to unaligned access\n", current->comm);
-                force_sig(SIGSEGV, current);
+uspace_segv:
+                printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
+                       "access (PC %lx PR %lx)\n", current->comm, regs->pc,
+                       regs->pr);
+
+                info.si_signo = SIGBUS;
+                info.si_errno = 0;
+                info.si_code = si_code;
+                info.si_addr = (void *) address;
+                force_sig_info(SIGBUS, &info, current);
         } else {
                 if (regs->pc & 1)
                         die("unaligned program counter", regs, error_code);
@@ -574,7 +585,9 @@ asmlinkage void do_address_error(struct pt_regs *regs,
                 handle_unaligned_access(instruction, regs);
                 set_fs(oldfs);
 #else
-                printk(KERN_NOTICE "Killing process \"%s\" due to unaligned access\n", current->comm);
+                printk(KERN_NOTICE "Killing process \"%s\" due to unaligned "
+                       "access\n", current->comm);
+
                 force_sig(SIGSEGV, current);
 #endif
         }
@@ -617,9 +630,6 @@ asmlinkage void do_divide_error(unsigned long r4, unsigned long r5,
         struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
         siginfo_t info;
 
-        current->thread.trap_no = r4;
-        current->thread.error_code = 0;
-
         switch (r4) {
         case TRAP_DIVZERO_ERROR:
                 info.si_code = FPE_INTDIV;
@@ -662,7 +672,7 @@ asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
 
 #ifdef CONFIG_SH_DSP
         /* Check if it's a DSP instruction */
-        if (is_dsp_inst(regs)) {
+        if (is_dsp_inst(regs)) {
                 /* Enable DSP mode, and restart instruction. */
                 regs->sr |= SR_DSP;
                 return;
@@ -672,8 +682,6 @@ asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
         lookup_exception_vector(error_code);
 
         local_irq_enable();
-        tsk->thread.error_code = error_code;
-        tsk->thread.trap_no = TRAP_RESERVED_INST;
         CHK_REMOTE_DEBUG(regs);
         force_sig(SIGILL, tsk);
         die_if_no_fixup("reserved instruction", regs, error_code);
@@ -745,8 +753,6 @@ asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5,
         lookup_exception_vector(error_code);
 
         local_irq_enable();
-        tsk->thread.error_code = error_code;
-        tsk->thread.trap_no = TRAP_RESERVED_INST;
         CHK_REMOTE_DEBUG(regs);
         force_sig(SIGILL, tsk);
         die_if_no_fixup("illegal slot instruction", regs, error_code);
@@ -805,7 +811,7 @@ void *set_exception_table_vec(unsigned int vec, void *handler)
 {
         extern void *exception_handling_table[];
         void *old_handler;
-        
+
         old_handler = exception_handling_table[vec];
         exception_handling_table[vec] = handler;
         return old_handler;
@@ -841,7 +847,7 @@ void __init trap_init(void)
         set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error);
         set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error);
 #endif
-                
+
         /* Setup VBR for boot cpu */
         per_cpu_trap_init();
 }