Commit: 9a93848fe787 ("x86/debug: Implement __WARN() using UD0") turned warnings into UD0, but the fixup code only runs after the notify_die() chain. This is a problem, in particular, with kgdb, which kicks in as if it was a BUG(). Fix this by running the fixup code before the notifier chain in the invalid op handler path.
Unified · Split
| @@ -209,9 +209,6 @@ do_trap_no_signal(struct task_struct *tsk, int trapnr, char *str, · 208 unmodified lines | ||
| 209 | 209 | if (fixup_exception(regs, trapnr)) |
| 210 | 210 | return 0; |
| 211 | 211 | |
| 212 | − if (fixup_bug(regs, trapnr)) | |
| 213 | − return 0; | |
| 214 | − | |
| 215 | 212 | tsk->thread.error_code = error_code; |
| 216 | 213 | tsk->thread.trap_nr = trapnr; |
| 217 | 214 | die(str, regs, error_code); |
| @@ -292,6 +289,13 @@ static void do_error_trap(struct pt_regs *regs, long error_code, char *str, · 74 unmodified lines | ||
| 292 | 289 | |
| 293 | 290 | RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); |
| 294 | 291 | |
| 292 | + /* | |
| 293 | + * WARN*()s end up here; fix them up before we call the | |
| 294 | + * notifier chain. | |
| 295 | + */ | |
| 296 | + if (!user_mode(regs) && fixup_bug(regs, trapnr)) | |
| 297 | + return; | |
| 298 | + | |
| 295 | 299 | if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) != |
| 296 | 300 | NOTIFY_STOP) { |
| 297 | 301 | cond_local_irq_enable(regs); |