1 files changed, 182 insertions, 53 deletions

diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c
index 53dfa55f3156..ec110157992d 100644
--- a/arch/sh/kernel/traps.c
+++ b/arch/sh/kernel/traps.c
@@ -18,13 +18,15 @@
 #include <linux/module.h>
 #include <linux/kallsyms.h>
 #include <linux/io.h>
+#include <linux/debug_locks.h>
+#include <linux/limits.h>
 #include <asm/system.h>
 #include <asm/uaccess.h>
 
 #ifdef CONFIG_SH_KGDB
 #include <asm/kgdb.h>
-#define CHK_REMOTE_DEBUG(regs)                  \
-{                                               \
+#define CHK_REMOTE_DEBUG(regs)                  \
+{                                               \
         if (kgdb_debug_hook && !user_mode(regs))\
                 (*kgdb_debug_hook)(regs);       \
 }
@@ -33,8 +35,13 @@
 #endif
 
 #ifdef CONFIG_CPU_SH2
-#define TRAP_RESERVED_INST      4
-#define TRAP_ILLEGAL_SLOT_INST  6
+# define TRAP_RESERVED_INST     4
+# define TRAP_ILLEGAL_SLOT_INST 6
+# define TRAP_ADDRESS_ERROR     9
+# ifdef CONFIG_CPU_SH2A
+#  define TRAP_DIVZERO_ERROR    17
+#  define TRAP_DIVOVF_ERROR     18
+# endif
 #else
 #define TRAP_RESERVED_INST      12
 #define TRAP_ILLEGAL_SLOT_INST  13
@@ -88,7 +95,7 @@ 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);
@@ -102,8 +109,6 @@ static inline void die_if_kernel(const char *str, struct pt_regs *regs,
                 die(str, regs, err);
 }
 
-static int handle_unaligned_notify_count = 10;
-
 /*
  * try and fix up kernelspace address errors
  * - userspace errors just cause EFAULT to be returned, resulting in SEGV
@@ -125,6 +130,40 @@ static int die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
         return -EFAULT;
 }
 
+#ifdef CONFIG_BUG
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+static inline void do_bug_verbose(struct pt_regs *regs)
+{
+        struct bug_frame f;
+        long len;
+
+        if (__copy_from_user(&f, (const void __user *)regs->pc,
+                             sizeof(struct bug_frame)))
+                return;
+
+        len = __strnlen_user(f.file, PATH_MAX) - 1;
+        if (unlikely(len < 0 || len >= PATH_MAX))
+                f.file = "<bad filename>";
+        len = __strnlen_user(f.func, PATH_MAX) - 1;
+        if (unlikely(len < 0 || len >= PATH_MAX))
+                f.func = "<bad function>";
+
+        printk(KERN_ALERT "kernel BUG in %s() at %s:%d!\n",
+               f.func, f.file, f.line);
+}
+#else
+static inline void do_bug_verbose(struct pt_regs *regs)
+{
+}
+#endif /* CONFIG_DEBUG_BUGVERBOSE */
+#endif /* CONFIG_BUG */
+
+void handle_BUG(struct pt_regs *regs)
+{
+        do_bug_verbose(regs);
+        die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff);
+}
+
 /*
  * handle an instruction that does an unaligned memory access by emulating the
  * desired behaviour
@@ -198,7 +237,7 @@ 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)
@@ -222,7 +261,7 @@ 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;
@@ -230,7 +269,7 @@ 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;
@@ -241,7 +280,7 @@ 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;
 
@@ -320,7 +359,8 @@ 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);
@@ -342,6 +382,13 @@ static inline int handle_unaligned_delayslot(struct pt_regs *regs)
 #define SH_PC_8BIT_OFFSET(instr) ((((signed char)(instr))*2) + 4)
 #define SH_PC_12BIT_OFFSET(instr) ((((signed short)(instr<<4))>>3) + 4)
 
+/*
+ * XXX: SH-2A needs this too, but it needs an overhaul thanks to mixed 32-bit
+ * opcodes..
+ */
+#ifndef CONFIG_CPU_SH2A
+static int handle_unaligned_notify_count = 10;
+
 static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
 {
         u_int rm;
@@ -354,7 +401,8 @@ 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);
         }
 
@@ -478,32 +526,58 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
                 regs->pc += 2;
         return ret;
 }
+#endif /* CONFIG_CPU_SH2A */
+
+#ifdef CONFIG_CPU_HAS_SR_RB
+#define lookup_exception_vector(x)      \
+        __asm__ __volatile__ ("stc r2_bank, %0\n\t" : "=r" ((x)))
+#else
+#define lookup_exception_vector(x)      \
+        __asm__ __volatile__ ("mov r4, %0\n\t" : "=r" ((x)))
+#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, 
+asmlinkage void do_address_error(struct pt_regs *regs,
                                  unsigned long writeaccess,
                                  unsigned long address)
 {
-        unsigned long error_code;
+        unsigned long error_code = 0;
         mm_segment_t oldfs;
+        siginfo_t info;
+#ifndef CONFIG_CPU_SH2A
         u16 instruction;
         int tmp;
+#endif
 
-        asm volatile("stc       r2_bank,%0": "=r" (error_code));
+        /* Intentional ifdef */
+#ifdef CONFIG_CPU_HAS_SR_RB
+        lookup_exception_vector(error_code);
+#endif
 
         oldfs = get_fs();
 
         if (user_mode(regs)) {
+                int si_code = BUS_ADRERR;
+
                 local_irq_enable();
-                current->thread.error_code = error_code;
-                current->thread.trap_no = (writeaccess) ? 8 : 7;
 
                 /* 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);
                 if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) {
                         /* Argh. Fault on the instruction itself.
@@ -518,14 +592,23 @@ asmlinkage void do_address_error(struct pt_regs *regs,
 
                 if (tmp==0)
                         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);
 
+#ifndef CONFIG_CPU_SH2A
                 set_fs(KERNEL_DS);
                 if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) {
                         /* Argh. Fault on the instruction itself.
@@ -537,6 +620,12 @@ 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);
+
+                force_sig(SIGSEGV, current);
+#endif
         }
 }
 
@@ -548,7 +637,7 @@ int is_dsp_inst(struct pt_regs *regs)
 {
         unsigned short inst;
 
-        /* 
+        /*
          * Safe guard if DSP mode is already enabled or we're lacking
          * the DSP altogether.
          */
@@ -569,27 +658,49 @@ int is_dsp_inst(struct pt_regs *regs)
 #define is_dsp_inst(regs)       (0)
 #endif /* CONFIG_SH_DSP */
 
+#ifdef CONFIG_CPU_SH2A
+asmlinkage void do_divide_error(unsigned long r4, unsigned long r5,
+                                unsigned long r6, unsigned long r7,
+                                struct pt_regs __regs)
+{
+        struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
+        siginfo_t info;
+
+        switch (r4) {
+        case TRAP_DIVZERO_ERROR:
+                info.si_code = FPE_INTDIV;
+                break;
+        case TRAP_DIVOVF_ERROR:
+                info.si_code = FPE_INTOVF;
+                break;
+        }
+
+        force_sig_info(SIGFPE, &info, current);
+}
+#endif
+
 /* arch/sh/kernel/cpu/sh4/fpu.c */
 extern int do_fpu_inst(unsigned short, struct pt_regs *);
 extern asmlinkage void do_fpu_state_restore(unsigned long r4, unsigned long r5,
-                unsigned long r6, unsigned long r7, struct pt_regs regs);
+                unsigned long r6, unsigned long r7, struct pt_regs __regs);
 
 asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
                                 unsigned long r6, unsigned long r7,
-                                struct pt_regs regs)
+                                struct pt_regs __regs)
 {
+        struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
         unsigned long error_code;
         struct task_struct *tsk = current;
 
 #ifdef CONFIG_SH_FPU_EMU
-        unsigned short inst;
+        unsigned short inst = 0;
         int err;
 
-        get_user(inst, (unsigned short*)regs.pc);
+        get_user(inst, (unsigned short*)regs->pc);
 
-        err = do_fpu_inst(inst, &regs);
+        err = do_fpu_inst(inst, regs);
         if (!err) {
-                regs.pc += 2;
+                regs->pc += 2;
                 return;
         }
         /* not a FPU inst. */
@@ -597,20 +708,19 @@ 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;
+                regs->sr |= SR_DSP;
                 return;
         }
 #endif
 
-        asm volatile("stc       r2_bank, %0": "=r" (error_code));
+        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);
+        CHK_REMOTE_DEBUG(regs);
         force_sig(SIGILL, tsk);
-        die_if_no_fixup("reserved instruction", &regs, error_code);
+        die_if_no_fixup("reserved instruction", regs, error_code);
 }
 
 #ifdef CONFIG_SH_FPU_EMU
@@ -658,39 +768,41 @@ static int emulate_branch(unsigned short inst, struct pt_regs* regs)
 
 asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5,
                                 unsigned long r6, unsigned long r7,
-                                struct pt_regs regs)
+                                struct pt_regs __regs)
 {
+        struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
         unsigned long error_code;
         struct task_struct *tsk = current;
 #ifdef CONFIG_SH_FPU_EMU
-        unsigned short inst;
+        unsigned short inst = 0;
 
-        get_user(inst, (unsigned short *)regs.pc + 1);
-        if (!do_fpu_inst(inst, &regs)) {
-                get_user(inst, (unsigned short *)regs.pc);
-                if (!emulate_branch(inst, &regs))
+        get_user(inst, (unsigned short *)regs->pc + 1);
+        if (!do_fpu_inst(inst, regs)) {
+                get_user(inst, (unsigned short *)regs->pc);
+                if (!emulate_branch(inst, regs))
                         return;
                 /* fault in branch.*/
         }
         /* not a FPU inst. */
 #endif
 
-        asm volatile("stc       r2_bank, %0": "=r" (error_code));
+        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);
+        CHK_REMOTE_DEBUG(regs);
         force_sig(SIGILL, tsk);
-        die_if_no_fixup("illegal slot instruction", &regs, error_code);
+        die_if_no_fixup("illegal slot instruction", regs, error_code);
 }
 
 asmlinkage void do_exception_error(unsigned long r4, unsigned long r5,
                                    unsigned long r6, unsigned long r7,
-                                   struct pt_regs regs)
+                                   struct pt_regs __regs)
 {
+        struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
         long ex;
-        asm volatile("stc       r2_bank, %0" : "=r" (ex));
-        die_if_kernel("exception", &regs, ex);
+
+        lookup_exception_vector(ex);
+        die_if_kernel("exception", regs, ex);
 }
 
 #if defined(CONFIG_SH_STANDARD_BIOS)
@@ -735,12 +847,16 @@ 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;
 }
 
+extern asmlinkage void address_error_handler(unsigned long r4, unsigned long r5,
+                                             unsigned long r6, unsigned long r7,
+                                             struct pt_regs __regs);
+
 void __init trap_init(void)
 {
         set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);
@@ -759,7 +875,15 @@ void __init trap_init(void)
         set_exception_table_evt(0x800, do_fpu_state_restore);
         set_exception_table_evt(0x820, do_fpu_state_restore);
 #endif
-                
+
+#ifdef CONFIG_CPU_SH2
+        set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_handler);
+#endif
+#ifdef CONFIG_CPU_SH2A
+        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();
 }
@@ -784,6 +908,11 @@ void show_trace(struct task_struct *tsk, unsigned long *sp,
         }
 
         printk("\n");
+
+        if (!tsk)
+                tsk = current;
+
+        debug_show_held_locks(tsk);
 }
 
 void show_stack(struct task_struct *tsk, unsigned long *sp)