sh: update die() output.
[pandora-kernel.git] / arch / sh / kernel / traps_32.c
index 2b77277..7a2ee3a 100644 (file)
@@ -24,6 +24,8 @@
 #include <linux/kdebug.h>
 #include <linux/kexec.h>
 #include <linux/limits.h>
+#include <linux/proc_fs.h>
+#include <linux/sysfs.h>
 #include <asm/system.h>
 #include <asm/uaccess.h>
 #include <asm/fpu.h>
 #define TRAP_ILLEGAL_SLOT_INST 13
 #endif
 
+static unsigned long se_user;
+static unsigned long se_sys;
+static unsigned long se_half;
+static unsigned long se_word;
+static unsigned long se_dword;
+static unsigned long se_multi;
+/* bitfield: 1: warn 2: fixup 4: signal -> combinations 2|4 && 1|2|4 are not
+   valid! */
+static int se_usermode = 3;
+/* 0: no warning 1: print a warning message, disabled by default */
+static int se_kernmode_warn;
+
+#ifdef CONFIG_PROC_FS
+static const char *se_usermode_action[] = {
+       "ignored",
+       "warn",
+       "fixup",
+       "fixup+warn",
+       "signal",
+       "signal+warn"
+};
+
+static int
+proc_alignment_read(char *page, char **start, off_t off, int count, int *eof,
+                   void *data)
+{
+       char *p = page;
+       int len;
+
+       p += sprintf(p, "User:\t\t%lu\n", se_user);
+       p += sprintf(p, "System:\t\t%lu\n", se_sys);
+       p += sprintf(p, "Half:\t\t%lu\n", se_half);
+       p += sprintf(p, "Word:\t\t%lu\n", se_word);
+       p += sprintf(p, "DWord:\t\t%lu\n", se_dword);
+       p += sprintf(p, "Multi:\t\t%lu\n", se_multi);
+       p += sprintf(p, "User faults:\t%i (%s)\n", se_usermode,
+                       se_usermode_action[se_usermode]);
+       p += sprintf(p, "Kernel faults:\t%i (fixup%s)\n", se_kernmode_warn,
+                       se_kernmode_warn ? "+warn" : "");
+
+       len = (p - page) - off;
+       if (len < 0)
+               len = 0;
+
+       *eof = (len <= count) ? 1 : 0;
+       *start = page + off;
+
+       return len;
+}
+
+static int proc_alignment_write(struct file *file, const char __user *buffer,
+                               unsigned long count, void *data)
+{
+       char mode;
+
+       if (count > 0) {
+               if (get_user(mode, buffer))
+                       return -EFAULT;
+               if (mode >= '0' && mode <= '5')
+                       se_usermode = mode - '0';
+       }
+       return count;
+}
+
+static int proc_alignment_kern_write(struct file *file, const char __user *buffer,
+                                    unsigned long count, void *data)
+{
+       char mode;
+
+       if (count > 0) {
+               if (get_user(mode, buffer))
+                       return -EFAULT;
+               if (mode >= '0' && mode <= '1')
+                       se_kernmode_warn = mode - '0';
+       }
+       return count;
+}
+#endif
+
 static void dump_mem(const char *str, unsigned long bottom, unsigned long top)
 {
        unsigned long p;
@@ -79,12 +160,12 @@ void die(const char * str, struct pt_regs * regs, long err)
 
        oops_enter();
 
-       console_verbose();
        spin_lock_irq(&die_lock);
+       console_verbose();
        bust_spinlocks(1);
 
        printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
-
+       sysfs_printk_last_file();
        print_modules();
        show_regs(regs);
 
@@ -100,6 +181,7 @@ void die(const char * str, struct pt_regs * regs, long err)
        bust_spinlocks(0);
        add_taint(TAINT_DIE);
        spin_unlock_irq(&die_lock);
+       oops_exit();
 
        if (kexec_should_crash(current))
                crash_kexec(regs);
@@ -110,7 +192,6 @@ void die(const char * str, struct pt_regs * regs, long err)
        if (panic_on_oops)
                panic("Fatal exception");
 
-       oops_exit();
        do_exit(SIGSEGV);
 }
 
@@ -136,6 +217,7 @@ static void die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
                        regs->pc = fixup->fixup;
                        return;
                }
+
                die(str, regs, err);
        }
 }
@@ -193,6 +275,13 @@ static int handle_unaligned_ins(insn_size_t instruction, struct pt_regs *regs,
 
        count = 1<<(instruction&3);
 
+       switch (count) {
+       case 1: se_half  += 1; break;
+       case 2: se_word  += 1; break;
+       case 4: se_dword += 1; break;
+       case 8: se_multi += 1; break; /* ??? */
+       }
+
        ret = -EFAULT;
        switch (instruction>>12) {
        case 0: /* mov.[bwl] to/from memory via r0+rn */
@@ -358,31 +447,28 @@ static inline int handle_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..
- */
-
-static int handle_unaligned_notify_count = 10;
-
 int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
-                           struct mem_access *ma)
+                           struct mem_access *ma, int expected)
 {
        u_int rm;
        int ret, index;
 
+       /*
+        * XXX: We can't handle mixed 16/32-bit instructions yet
+        */
+       if (instruction_size(instruction) != 2)
+               return -EINVAL;
+
        index = (instruction>>8)&15;    /* 0x0F00 */
        rm = regs->regs[index];
 
-       /* shout about the first ten userspace fixups */
-       if (user_mode(regs) && handle_unaligned_notify_count>0) {
-               handle_unaligned_notify_count--;
-
-               printk(KERN_NOTICE "Fixing up unaligned userspace access "
+       /* shout about fixups */
+       if (!expected && printk_ratelimit())
+               printk(KERN_NOTICE "Fixing up unaligned %s access "
                       "in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
+                      user_mode(regs) ? "userspace" : "kernel",
                       current->comm, task_pid_nr(current),
                       (void *)regs->pc, instruction);
-       }
 
        ret = -EFAULT;
        switch (instruction&0xF000) {
@@ -538,24 +624,44 @@ asmlinkage void do_address_error(struct pt_regs *regs,
 
                local_irq_enable();
 
-               /* bad PC is not something we can fix */
-               if (regs->pc & 1) {
-                       si_code = BUS_ADRALN;
-                       goto uspace_segv;
-               }
+               se_user += 1;
 
                set_fs(USER_DS);
-               if (copy_from_user(&instruction, (void __user *)(regs->pc),
+               if (copy_from_user(&instruction, (insn_size_t *)(regs->pc & ~1),
                                   sizeof(instruction))) {
-                       /* Argh. Fault on the instruction itself.
-                          This should never happen non-SMP
-                       */
                        set_fs(oldfs);
                        goto uspace_segv;
                }
+               set_fs(oldfs);
+
+               /* shout about userspace fixups */
+               if (se_usermode & 1)
+                       printk(KERN_NOTICE "Unaligned userspace access "
+                              "in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
+                              current->comm, current->pid, (void *)regs->pc,
+                              instruction);
+
+               if (se_usermode & 2)
+                       goto fixup;
+
+               if (se_usermode & 4)
+                       goto uspace_segv;
+               else {
+                       /* ignore */
+                       regs->pc += instruction_size(instruction);
+                       return;
+               }
+
+fixup:
+               /* bad PC is not something we can fix */
+               if (regs->pc & 1) {
+                       si_code = BUS_ADRALN;
+                       goto uspace_segv;
+               }
 
+               set_fs(USER_DS);
                tmp = handle_unaligned_access(instruction, regs,
-                                             &user_mem_access);
+                                             &user_mem_access, 0);
                set_fs(oldfs);
 
                if (tmp==0)
@@ -571,6 +677,8 @@ uspace_segv:
                info.si_addr = (void __user *)address;
                force_sig_info(SIGBUS, &info, current);
        } else {
+               se_sys += 1;
+
                if (regs->pc & 1)
                        die("unaligned program counter", regs, error_code);
 
@@ -584,7 +692,14 @@ uspace_segv:
                        die("insn faulting in do_address_error", regs, 0);
                }
 
-               handle_unaligned_access(instruction, regs, &user_mem_access);
+               if (se_kernmode_warn)
+                       printk(KERN_NOTICE "Unaligned kernel access "
+                              "on behalf of \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
+                              current->comm, current->pid, (void *)regs->pc,
+                              instruction);
+
+               handle_unaligned_access(instruction, regs,
+                                       &user_mem_access, 0);
                set_fs(oldfs);
        }
 }
@@ -858,30 +973,6 @@ void __init trap_init(void)
        per_cpu_trap_init();
 }
 
-void show_trace(struct task_struct *tsk, unsigned long *sp,
-               struct pt_regs *regs)
-{
-       unsigned long addr;
-
-       if (regs && user_mode(regs))
-               return;
-
-       printk("\nCall trace:\n");
-
-       while (!kstack_end(sp)) {
-               addr = *sp++;
-               if (kernel_text_address(addr))
-                       print_ip_sym(addr);
-       }
-
-       printk("\n");
-
-       if (!tsk)
-               tsk = current;
-
-       debug_show_held_locks(tsk);
-}
-
 void show_stack(struct task_struct *tsk, unsigned long *sp)
 {
        unsigned long stack;
@@ -904,3 +995,38 @@ void dump_stack(void)
        show_stack(NULL, NULL);
 }
 EXPORT_SYMBOL(dump_stack);
+
+#ifdef CONFIG_PROC_FS
+/*
+ * This needs to be done after sysctl_init, otherwise sys/ will be
+ * overwritten.  Actually, this shouldn't be in sys/ at all since
+ * it isn't a sysctl, and it doesn't contain sysctl information.
+ * We now locate it in /proc/cpu/alignment instead.
+ */
+static int __init alignment_init(void)
+{
+       struct proc_dir_entry *dir, *res;
+
+       dir = proc_mkdir("cpu", NULL);
+       if (!dir)
+               return -ENOMEM;
+
+       res = create_proc_entry("alignment", S_IWUSR | S_IRUGO, dir);
+       if (!res)
+               return -ENOMEM;
+
+       res->read_proc = proc_alignment_read;
+       res->write_proc = proc_alignment_write;
+
+        res = create_proc_entry("kernel_alignment", S_IWUSR | S_IRUGO, dir);
+        if (!res)
+                return -ENOMEM;
+
+        res->read_proc = proc_alignment_read;
+        res->write_proc = proc_alignment_kern_write;
+
+       return 0;
+}
+
+fs_initcall(alignment_init);
+#endif