[PARISC] Generic BUG

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>

5 files changed, 116 insertions, 53 deletions

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 0f9ff618c6d7..848a67a024b2 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -37,6 +37,11 @@ config GENERIC_FIND_NEXT_BIT
         bool
         default y
 
+config GENERIC_BUG
+        bool
+        default y
+        depends on BUG
+
 config GENERIC_HWEIGHT
         bool
         default y
diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c
index 47ea4e4a2179..1808f857a73a 100644
--- a/arch/parisc/kernel/module.c
+++ b/arch/parisc/kernel/module.c
@@ -46,6 +46,7 @@
 #include <linux/fs.h>
 #include <linux/string.h>
 #include <linux/kernel.h>
+#include <linux/bug.h>
 
 #include <asm/unwind.h>
 
@@ -851,10 +852,11 @@ int module_finalize(const Elf_Ehdr *hdr,
         nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
         DEBUGP("NEW num_symtab %lu\n", nsyms);
         symhdr->sh_size = nsyms * sizeof(Elf_Sym);
-        return 0;
+        return module_bug_finalize(hdr, sechdrs, me);
 }
 
 void module_arch_cleanup(struct module *mod)
 {
         deregister_unwind_table(mod);
+        module_bug_cleanup(mod);
 }
diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c
index 949722540864..ea0eff91db4e 100644
--- a/arch/parisc/kernel/traps.c
+++ b/arch/parisc/kernel/traps.c
@@ -26,6 +26,7 @@
 #include <linux/interrupt.h>
 #include <linux/console.h>
 #include <linux/kallsyms.h>
+#include <linux/bug.h>
 
 #include <asm/assembly.h>
 #include <asm/system.h>
@@ -51,7 +52,7 @@
 DEFINE_SPINLOCK(pa_dbit_lock);
 #endif
 
-int printbinary(char *buf, unsigned long x, int nbits)
+static int printbinary(char *buf, unsigned long x, int nbits)
 {
         unsigned long mask = 1UL << (nbits - 1);
         while (mask != 0) {
@@ -207,6 +208,11 @@ HERE:
         do_show_stack(&info);
 }
 
+int is_valid_bugaddr(unsigned long iaoq)
+{
+        return 1;
+}
+
 void die_if_kernel(char *str, struct pt_regs *regs, long err)
 {
         if (user_mode(regs)) {
@@ -225,7 +231,7 @@ void die_if_kernel(char *str, struct pt_regs *regs, long err)
         oops_in_progress = 1;
 
         /* Amuse the user in a SPARC fashion */
-        printk(
+        if (err) printk(
 "      _______________________________ \n"
 "     < Your System ate a SPARC! Gah! >\n"
 "      ------------------------------- \n"
@@ -245,8 +251,9 @@ void die_if_kernel(char *str, struct pt_regs *regs, long err)
         if (!console_drivers)
                 pdc_console_restart();
         
-        printk(KERN_CRIT "%s (pid %d): %s (code %ld)\n",
-                current->comm, current->pid, str, err);
+        if (err)
+                printk(KERN_CRIT "%s (pid %d): %s (code %ld)\n",
+                        current->comm, current->pid, str, err);
         show_regs(regs);
 
         if (in_interrupt())
@@ -276,61 +283,45 @@ int syscall_ipi(int (*syscall) (struct pt_regs *), struct pt_regs *regs)
 
 /* gdb uses break 4,8 */
 #define GDB_BREAK_INSN 0x10004
-void handle_gdb_break(struct pt_regs *regs, int wot)
+static void handle_gdb_break(struct pt_regs *regs, int wot)
 {
         struct siginfo si;
 
-        si.si_code = wot;
-        si.si_addr = (void __user *) (regs->iaoq[0] & ~3);
         si.si_signo = SIGTRAP;
         si.si_errno = 0;
+        si.si_code = wot;
+        si.si_addr = (void __user *) (regs->iaoq[0] & ~3);
         force_sig_info(SIGTRAP, &si, current);
 }
 
-void handle_break(unsigned iir, struct pt_regs *regs)
+static void handle_break(struct pt_regs *regs)
 {
-        struct siginfo si;
-
-        switch(iir) {
-        case 0x00:
-#ifdef PRINT_USER_FAULTS
-                printk(KERN_DEBUG "break 0,0: pid=%d command='%s'\n",
-                       current->pid, current->comm);
-#endif
-                die_if_kernel("Breakpoint", regs, 0);
-#ifdef PRINT_USER_FAULTS
-                show_regs(regs);
-#endif
-                si.si_code = TRAP_BRKPT;
-                si.si_addr = (void __user *) (regs->iaoq[0] & ~3);
-                si.si_signo = SIGTRAP;
-                force_sig_info(SIGTRAP, &si, current);
-                break;
-
-        case GDB_BREAK_INSN:
-                die_if_kernel("Breakpoint", regs, 0);
-                handle_gdb_break(regs, TRAP_BRKPT);
-                break;
+        unsigned iir = regs->iir;
+
+        if (unlikely(iir == PARISC_BUG_BREAK_INSN && !user_mode(regs))) {
+                /* check if a BUG() or WARN() trapped here.  */
+                enum bug_trap_type tt;
+                tt = report_bug(regs->iaoq[0] & ~3);
+                if (tt == BUG_TRAP_TYPE_WARN) {
+                        regs->iaoq[0] += 4;
+                        regs->iaoq[1] += 4;
+                        return; /* return to next instruction when WARN_ON().  */
+                }
+                die_if_kernel("Unknown kernel breakpoint", regs,
+                        (tt == BUG_TRAP_TYPE_NONE) ? 9 : 0);
+        }
 
-        default:
 #ifdef PRINT_USER_FAULTS
-                printk(KERN_DEBUG "break %#08x: pid=%d command='%s'\n",
-                       iir, current->pid, current->comm);
+        if (unlikely(iir != GDB_BREAK_INSN)) {
+                printk(KERN_DEBUG "break %d,%d: pid=%d command='%s'\n",
+                        (iir>>13) & ((1<<13)-1), iir & 31,
+                        current->pid, current->comm);
                 show_regs(regs);
-#endif
-                si.si_signo = SIGTRAP;
-                si.si_code = TRAP_BRKPT;
-                si.si_addr = (void __user *) (regs->iaoq[0] & ~3);
-                force_sig_info(SIGTRAP, &si, current);
-                return;
         }
-}
-
+#endif
 
-int handle_toc(void)
-{
-        printk(KERN_CRIT "TOC call.\n");
-        return 0;
+        /* send standard GDB signal */
+        handle_gdb_break(regs, TRAP_BRKPT);
 }
 
 static void default_trap(int code, struct pt_regs *regs)
@@ -339,7 +330,7 @@ static void default_trap(int code, struct pt_regs *regs)
         show_regs(regs);
 }
 
-void (*cpu_lpmc) (int code, struct pt_regs *regs) = default_trap;
+void (*cpu_lpmc) (int code, struct pt_regs *regs) __read_mostly = default_trap;
 
 
 void transfer_pim_to_trap_frame(struct pt_regs *regs)
@@ -576,7 +567,7 @@ void handle_interruption(int code, struct pt_regs *regs)
 
         case  9:
                 /* Break instruction trap */
-                handle_break(regs->iir,regs);
+                handle_break(regs);
                 return;
         
         case 10:
diff --git a/arch/parisc/kernel/vmlinux.lds.S b/arch/parisc/kernel/vmlinux.lds.S
index 7b943b45f7cd..7b149df9d422 100644
--- a/arch/parisc/kernel/vmlinux.lds.S
+++ b/arch/parisc/kernel/vmlinux.lds.S
@@ -68,6 +68,8 @@ SECTIONS
 
   RODATA
 
+  BUG_TABLE
+
   /* writeable */
   . = ALIGN(ASM_PAGE_SIZE);     /* Make sure this is page aligned so
                                    that we can properly leave these
diff --git a/include/asm-parisc/bug.h b/include/asm-parisc/bug.h
index 695588da41f8..8dd199f5d6d7 100644
--- a/include/asm-parisc/bug.h
+++ b/include/asm-parisc/bug.h
@@ -1,14 +1,77 @@
 #ifndef _PARISC_BUG_H
 #define _PARISC_BUG_H
 
+/*
+ * Tell the user there is some problem.
+ * The offending file and line are encoded in the __bug_table section.
+ */
+
 #ifdef CONFIG_BUG
 #define HAVE_ARCH_BUG
-#define BUG() do { \
-        printk("kernel BUG at %s:%d!\n", __FILE__, __LINE__); \
-        dump_stack(); \
-        panic("BUG!"); \
-} while (0)
+#define HAVE_ARCH_WARN_ON
+
+/* the break instruction is used as BUG() marker.  */
+#define PARISC_BUG_BREAK_ASM    "break 0x1f, 0x1fff"
+#define PARISC_BUG_BREAK_INSN   0x03ffe01f  /* PARISC_BUG_BREAK_ASM */
+
+#ifdef CONFIG_64BIT
+#define ASM_ULONG_INSN          ".dword"
+#else
+#define ASM_ULONG_INSN          ".word"
+#endif
+
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+#define BUG()                                                           \
+        do {                                                            \
+                asm volatile("\n"                                       \
+                             "1:\t" PARISC_BUG_BREAK_ASM "\n"           \
+                             "\t.pushsection __bug_table,\"a\"\n"       \
+                             "2:\t" ASM_ULONG_INSN " 1b, %c0\n"         \
+                             "\t.short %c1, %c2\n"                      \
+                             "\t.org 2b+%c3\n"                          \
+                             "\t.popsection"                            \
+                             : : "i" (__FILE__), "i" (__LINE__),        \
+                             "i" (0), "i" (sizeof(struct bug_entry)) ); \
+                for(;;) ;                                               \
+        } while(0)
+
+#else
+#define BUG()                                                           \
+        do {                                                            \
+                asm volatile(PARISC_BUG_BREAK_ASM : : );                \
+                for(;;) ;                                               \
+        } while(0)
+#endif
+
+#define __WARN()                                                        \
+        do {                                                            \
+                asm volatile("\n"                                       \
+                             "1:\t" PARISC_BUG_BREAK_ASM "\n"           \
+                             "\t.pushsection __bug_table,\"a\"\n"       \
+                             "2:\t" ASM_ULONG_INSN " 1b, %c0\n"         \
+                             "\t.short %c1, %c2\n"                      \
+                             "\t.org 2b+%c3\n"                          \
+                             "\t.popsection"                            \
+                             : : "i" (__FILE__), "i" (__LINE__),        \
+                             "i" (BUGFLAG_WARNING),                     \
+                             "i" (sizeof(struct bug_entry)) );          \
+        } while(0)
+
+
+#define WARN_ON(x) ({                                           \
+        typeof(x) __ret_warn_on = (x);                          \
+        if (__builtin_constant_p(__ret_warn_on)) {              \
+                if (__ret_warn_on)                              \
+                        __WARN();                               \
+        } else {                                                \
+                if (unlikely(__ret_warn_on))                    \
+                        __WARN();                               \
+        }                                                       \
+        unlikely(__ret_warn_on);                                \
+})
+
 #endif
 
 #include <asm-generic/bug.h>
 #endif
+