diff options
Diffstat (limited to 'lib/bug.c')
-rw-r--r-- | lib/bug.c | 95 |
1 files changed, 59 insertions, 36 deletions
diff --git a/lib/bug.c b/lib/bug.c index 1077366f496b..e0ff21989990 100644 --- a/lib/bug.c +++ b/lib/bug.c @@ -6,8 +6,7 @@ CONFIG_BUG - emit BUG traps. Nothing happens without this. CONFIG_GENERIC_BUG - enable this code. - CONFIG_GENERIC_BUG_RELATIVE_POINTERS - use 32-bit pointers relative to - the containing struct bug_entry for bug_addr and file. + CONFIG_GENERIC_BUG_RELATIVE_POINTERS - use 32-bit relative pointers for bug_addr and file CONFIG_DEBUG_BUGVERBOSE - emit full file+line information for each BUG CONFIG_BUG and CONFIG_DEBUG_BUGVERBOSE are potentially user-settable @@ -47,15 +46,17 @@ #include <linux/bug.h> #include <linux/sched.h> #include <linux/rculist.h> +#include <linux/ftrace.h> +#include <linux/context_tracking.h> extern struct bug_entry __start___bug_table[], __stop___bug_table[]; static inline unsigned long bug_addr(const struct bug_entry *bug) { -#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS - return bug->bug_addr; +#ifdef CONFIG_GENERIC_BUG_RELATIVE_POINTERS + return (unsigned long)&bug->bug_addr_disp + bug->bug_addr_disp; #else - return (unsigned long)bug + bug->bug_addr_disp; + return bug->bug_addr; #endif } @@ -90,8 +91,6 @@ void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, char *secstrings; unsigned int i; - lockdep_assert_held(&module_mutex); - mod->bug_table = NULL; mod->num_bugs = 0; @@ -117,7 +116,6 @@ void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, void module_bug_cleanup(struct module *mod) { - lockdep_assert_held(&module_mutex); list_del_rcu(&mod->bug_list); } @@ -129,6 +127,22 @@ static inline struct bug_entry *module_find_bug(unsigned long bugaddr) } #endif +void bug_get_file_line(struct bug_entry *bug, const char **file, + unsigned int *line) +{ +#ifdef CONFIG_DEBUG_BUGVERBOSE +#ifdef CONFIG_GENERIC_BUG_RELATIVE_POINTERS + *file = (const char *)&bug->file_disp + bug->file_disp; +#else + *file = bug->file; +#endif + *line = bug->line; +#else + *file = NULL; + *line = 0; +#endif +} + struct bug_entry *find_bug(unsigned long bugaddr) { struct bug_entry *bug; @@ -140,7 +154,7 @@ struct bug_entry *find_bug(unsigned long bugaddr) return module_find_bug(bugaddr); } -enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs) +static enum bug_trap_type __report_bug(unsigned long bugaddr, struct pt_regs *regs) { struct bug_entry *bug; const char *file; @@ -153,34 +167,33 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs) if (!bug) return BUG_TRAP_TYPE_NONE; - file = NULL; - line = 0; - warning = 0; + disable_trace_on_warning(); - if (bug) { -#ifdef CONFIG_DEBUG_BUGVERBOSE -#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS - file = bug->file; -#else - file = (const char *)bug + bug->file_disp; -#endif - line = bug->line; -#endif - warning = (bug->flags & BUGFLAG_WARNING) != 0; - once = (bug->flags & BUGFLAG_ONCE) != 0; - done = (bug->flags & BUGFLAG_DONE) != 0; - - if (warning && once) { - if (done) - return BUG_TRAP_TYPE_WARN; - - /* - * Since this is the only store, concurrency is not an issue. - */ - bug->flags |= BUGFLAG_DONE; - } + bug_get_file_line(bug, &file, &line); + + warning = (bug->flags & BUGFLAG_WARNING) != 0; + once = (bug->flags & BUGFLAG_ONCE) != 0; + done = (bug->flags & BUGFLAG_DONE) != 0; + + if (warning && once) { + if (done) + return BUG_TRAP_TYPE_WARN; + + /* + * Since this is the only store, concurrency is not an issue. + */ + bug->flags |= BUGFLAG_DONE; } + /* + * BUG() and WARN_ON() families don't print a custom debug message + * before triggering the exception handler, so we must add the + * "cut here" line now. WARN() issues its own "cut here" before the + * extra debugging message it writes before triggering the handler. + */ + if ((bug->flags & BUGFLAG_NO_CUT_HERE) == 0) + printk(KERN_DEFAULT CUT_HERE); + if (warning) { /* this is a WARN_ON rather than BUG/BUG_ON */ __warn(file, line, (void *)bugaddr, BUG_GET_TAINT(bug), regs, @@ -188,8 +201,6 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs) return BUG_TRAP_TYPE_WARN; } - printk(KERN_DEFAULT CUT_HERE); - if (file) pr_crit("kernel BUG at %s:%u!\n", file, line); else @@ -199,6 +210,18 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs) return BUG_TRAP_TYPE_BUG; } +enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs) +{ + enum bug_trap_type ret; + bool rcu = false; + + rcu = warn_rcu_enter(); + ret = __report_bug(bugaddr, regs); + warn_rcu_exit(rcu); + + return ret; +} + static void clear_once_table(struct bug_entry *start, struct bug_entry *end) { struct bug_entry *bug; |