--- /dev/null
+#ifndef _LINUX_BUG_H
+#define _LINUX_BUG_H
+
+#include <linux/module.h>
+#include <asm/bug.h>
+
+enum bug_trap_type {
+ BUG_TRAP_TYPE_NONE = 0,
+ BUG_TRAP_TYPE_WARN = 1,
+ BUG_TRAP_TYPE_BUG = 2,
+};
+
+#ifdef CONFIG_GENERIC_BUG
+#include <asm-generic/bug.h>
+
+static inline int is_warning_bug(const struct bug_entry *bug)
+{
+ return bug->flags & BUGFLAG_WARNING;
+}
+
+const struct bug_entry *find_bug(unsigned long bugaddr);
+
+enum bug_trap_type report_bug(unsigned long bug_addr);
+
+int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
+ struct module *);
+void module_bug_cleanup(struct module *);
+
+/* These are defined by the architecture */
+int is_valid_bugaddr(unsigned long addr);
+
+#else /* !CONFIG_GENERIC_BUG */
+
+static inline enum bug_trap_type report_bug(unsigned long bug_addr)
+{
+ return BUG_TRAP_TYPE_BUG;
+}
+static inline int module_bug_finalize(const Elf_Ehdr *hdr,
+ const Elf_Shdr *sechdrs,
+ struct module *mod)
+{
+ return 0;
+}
+static inline void module_bug_cleanup(struct module *mod) {}
+
+#endif /* CONFIG_GENERIC_BUG */
+#endif /* _LINUX_BUG_H */
--- /dev/null
+/*
+ Generic support for BUG()
+
+ This respects the following config options:
+
+ CONFIG_BUG - emit BUG traps. Nothing happens without this.
+ CONFIG_GENERIC_BUG - enable this code.
+ CONFIG_DEBUG_BUGVERBOSE - emit full file+line information for each BUG
+
+ CONFIG_BUG and CONFIG_DEBUG_BUGVERBOSE are potentially user-settable
+ (though they're generally always on).
+
+ CONFIG_GENERIC_BUG is set by each architecture using this code.
+
+ To use this, your architecture must:
+
+ 1. Set up the config options:
+ - Enable CONFIG_GENERIC_BUG if CONFIG_BUG
+
+ 2. Implement BUG (and optionally BUG_ON, WARN, WARN_ON)
+ - Define HAVE_ARCH_BUG
+ - Implement BUG() to generate a faulting instruction
+ - NOTE: struct bug_entry does not have "file" or "line" entries
+ when CONFIG_DEBUG_BUGVERBOSE is not enabled, so you must generate
+ the values accordingly.
+
+ 3. Implement the trap
+ - In the illegal instruction trap handler (typically), verify
+ that the fault was in kernel mode, and call report_bug()
+ - report_bug() will return whether it was a false alarm, a warning,
+ or an actual bug.
+ - You must implement the is_valid_bugaddr(bugaddr) callback which
+ returns true if the eip is a real kernel address, and it points
+ to the expected BUG trap instruction.
+
+ Jeremy Fitzhardinge <jeremy@goop.org> 2006
+ */
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/bug.h>
+
+extern const struct bug_entry __start___bug_table[], __stop___bug_table[];
+
+#ifdef CONFIG_MODULES
+static LIST_HEAD(module_bug_list);
+
+static const struct bug_entry *module_find_bug(unsigned long bugaddr)
+{
+ struct module *mod;
+
+ list_for_each_entry(mod, &module_bug_list, bug_list) {
+ const struct bug_entry *bug = mod->bug_table;
+ unsigned i;
+
+ for (i = 0; i < mod->num_bugs; ++i, ++bug)
+ if (bugaddr == bug->bug_addr)
+ return bug;
+ }
+ return NULL;
+}
+
+int module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
+ struct module *mod)
+{
+ char *secstrings;
+ unsigned int i;
+
+ mod->bug_table = NULL;
+ mod->num_bugs = 0;
+
+ /* Find the __bug_table section, if present */
+ secstrings = (char *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+ for (i = 1; i < hdr->e_shnum; i++) {
+ if (strcmp(secstrings+sechdrs[i].sh_name, "__bug_table"))
+ continue;
+ mod->bug_table = (void *) sechdrs[i].sh_addr;
+ mod->num_bugs = sechdrs[i].sh_size / sizeof(struct bug_entry);
+ break;
+ }
+
+ /*
+ * Strictly speaking this should have a spinlock to protect against
+ * traversals, but since we only traverse on BUG()s, a spinlock
+ * could potentially lead to deadlock and thus be counter-productive.
+ */
+ list_add(&mod->bug_list, &module_bug_list);
+
+ return 0;
+}
+
+void module_bug_cleanup(struct module *mod)
+{
+ list_del(&mod->bug_list);
+}
+
+#else
+
+static inline const struct bug_entry *module_find_bug(unsigned long bugaddr)
+{
+ return NULL;
+}
+#endif
+
+const struct bug_entry *find_bug(unsigned long bugaddr)
+{
+ const struct bug_entry *bug;
+
+ for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
+ if (bugaddr == bug->bug_addr)
+ return bug;
+
+ return module_find_bug(bugaddr);
+}
+
+enum bug_trap_type report_bug(unsigned long bugaddr)
+{
+ const struct bug_entry *bug;
+ const char *file;
+ unsigned line, warning;
+
+ if (!is_valid_bugaddr(bugaddr))
+ return BUG_TRAP_TYPE_NONE;
+
+ bug = find_bug(bugaddr);
+
+ printk(KERN_EMERG "------------[ cut here ]------------\n");
+
+ file = NULL;
+ line = 0;
+ warning = 0;
+
+ if (bug) {
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+ file = bug->file;
+ line = bug->line;
+#endif
+ warning = (bug->flags & BUGFLAG_WARNING) != 0;
+ }
+
+ if (warning) {
+ /* this is a WARN_ON rather than BUG/BUG_ON */
+ if (file)
+ printk(KERN_ERR "Badness at %s:%u\n",
+ file, line);
+ else
+ printk(KERN_ERR "Badness at %p "
+ "[verbose debug info unavailable]\n",
+ (void *)bugaddr);
+
+ dump_stack();
+ return BUG_TRAP_TYPE_WARN;
+ }
+
+ if (file)
+ printk(KERN_CRIT "kernel BUG at %s:%u!\n",
+ file, line);
+ else
+ printk(KERN_CRIT "Kernel BUG at %p "
+ "[verbose debug info unavailable]\n",
+ (void *)bugaddr);
+
+ return BUG_TRAP_TYPE_BUG;
+}
projects / linux-2.6 / commitdiff