diff options
Diffstat (limited to 'arch/x86/kernel/traps.c')
| -rw-r--r-- | arch/x86/kernel/traps.c | 33 |
1 files changed, 19 insertions, 14 deletions
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 2d1f4c7e405..ce6650eb64e 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -292,8 +292,10 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) tsk->thread.error_code = error_code; tsk->thread.trap_no = 8; - /* This is always a kernel trap and never fixable (and thus must - never return). */ + /* + * This is always a kernel trap and never fixable (and thus must + * never return). + */ for (;;) die(str, regs, error_code); } @@ -520,9 +522,11 @@ dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code) } #ifdef CONFIG_X86_64 -/* Help handler running on IST stack to switch back to user stack - for scheduling or signal handling. The actual stack switch is done in - entry.S */ +/* + * Help handler running on IST stack to switch back to user stack + * for scheduling or signal handling. The actual stack switch is done in + * entry.S + */ asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) { struct pt_regs *regs = eregs; @@ -532,8 +536,10 @@ asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) /* Exception from user space */ else if (user_mode(eregs)) regs = task_pt_regs(current); - /* Exception from kernel and interrupts are enabled. Move to - kernel process stack. */ + /* + * Exception from kernel and interrupts are enabled. Move to + * kernel process stack. + */ else if (eregs->flags & X86_EFLAGS_IF) regs = (struct pt_regs *)(eregs->sp -= sizeof(struct pt_regs)); if (eregs != regs) @@ -685,12 +691,7 @@ void math_error(void __user *ip) cwd = get_fpu_cwd(task); swd = get_fpu_swd(task); - err = swd & ~cwd & 0x3f; - -#ifdef CONFIG_X86_32 - if (!err) - return; -#endif + err = swd & ~cwd; if (err & 0x001) { /* Invalid op */ /* @@ -708,7 +709,11 @@ void math_error(void __user *ip) } else if (err & 0x020) { /* Precision */ info.si_code = FPE_FLTRES; } else { - info.si_code = __SI_FAULT|SI_KERNEL; /* WTF? */ + /* + * If we're using IRQ 13, or supposedly even some trap 16 + * implementations, it's possible we get a spurious trap... + */ + return; /* Spurious trap, no error */ } force_sig_info(SIGFPE, &info, task); } |