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-rw-r--r--arch/x86/kernel/traps.c77
1 files changed, 37 insertions, 40 deletions
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 04d242ab016..c9a666cdd3d 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -20,7 +20,6 @@
#include <linux/module.h>
#include <linux/ptrace.h>
#include <linux/string.h>
-#include <linux/unwind.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/kexec.h>
@@ -51,7 +50,6 @@
#include <asm/debugreg.h>
#include <asm/atomic.h>
#include <asm/system.h>
-#include <asm/unwind.h>
#include <asm/traps.h>
#include <asm/desc.h>
#include <asm/i387.h>
@@ -72,9 +70,6 @@
#include "cpu/mcheck/mce.h"
-DECLARE_BITMAP(used_vectors, NR_VECTORS);
-EXPORT_SYMBOL_GPL(used_vectors);
-
asmlinkage int system_call(void);
/* Do we ignore FPU interrupts ? */
@@ -89,6 +84,9 @@ gate_desc idt_table[256]
__attribute__((__section__(".data.idt"))) = { { { { 0, 0 } } }, };
#endif
+DECLARE_BITMAP(used_vectors, NR_VECTORS);
+EXPORT_SYMBOL_GPL(used_vectors);
+
static int ignore_nmis;
static inline void conditional_sti(struct pt_regs *regs)
@@ -292,8 +290,10 @@ 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);
}
@@ -481,11 +481,7 @@ do_nmi(struct pt_regs *regs, long error_code)
{
nmi_enter();
-#ifdef CONFIG_X86_32
- { int cpu; cpu = smp_processor_id(); ++nmi_count(cpu); }
-#else
- add_pda(__nmi_count, 1);
-#endif
+ inc_irq_stat(__nmi_count);
if (!ignore_nmis)
default_do_nmi(regs);
@@ -524,9 +520,11 @@ 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;
@@ -536,8 +534,10 @@ 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)
@@ -664,7 +664,7 @@ void math_error(void __user *ip)
{
struct task_struct *task;
siginfo_t info;
- unsigned short cwd, swd;
+ unsigned short cwd, swd, err;
/*
* Save the info for the exception handler and clear the error.
@@ -675,7 +675,6 @@ void math_error(void __user *ip)
task->thread.error_code = 0;
info.si_signo = SIGFPE;
info.si_errno = 0;
- info.si_code = __SI_FAULT;
info.si_addr = ip;
/*
* (~cwd & swd) will mask out exceptions that are not set to unmasked
@@ -689,34 +688,30 @@ void math_error(void __user *ip)
*/
cwd = get_fpu_cwd(task);
swd = get_fpu_swd(task);
- switch (swd & ~cwd & 0x3f) {
- case 0x000: /* No unmasked exception */
-#ifdef CONFIG_X86_32
- return;
-#endif
- default: /* Multiple exceptions */
- break;
- case 0x001: /* Invalid Op */
+
+ err = swd & ~cwd;
+
+ if (err & 0x001) { /* Invalid op */
/*
* swd & 0x240 == 0x040: Stack Underflow
* swd & 0x240 == 0x240: Stack Overflow
* User must clear the SF bit (0x40) if set
*/
info.si_code = FPE_FLTINV;
- break;
- case 0x002: /* Denormalize */
- case 0x010: /* Underflow */
- info.si_code = FPE_FLTUND;
- break;
- case 0x004: /* Zero Divide */
+ } else if (err & 0x004) { /* Divide by Zero */
info.si_code = FPE_FLTDIV;
- break;
- case 0x008: /* Overflow */
+ } else if (err & 0x008) { /* Overflow */
info.si_code = FPE_FLTOVF;
- break;
- case 0x020: /* Precision */
+ } else if (err & 0x012) { /* Denormal, Underflow */
+ info.si_code = FPE_FLTUND;
+ } else if (err & 0x020) { /* Precision */
info.si_code = FPE_FLTRES;
- break;
+ } else {
+ /*
+ * 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);
}
@@ -949,9 +944,7 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
void __init trap_init(void)
{
-#ifdef CONFIG_X86_32
int i;
-#endif
#ifdef CONFIG_EISA
void __iomem *p = early_ioremap(0x0FFFD9, 4);
@@ -1008,11 +1001,15 @@ void __init trap_init(void)
}
set_system_trap_gate(SYSCALL_VECTOR, &system_call);
+#endif
/* Reserve all the builtin and the syscall vector: */
for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
set_bit(i, used_vectors);
+#ifdef CONFIG_X86_64
+ set_bit(IA32_SYSCALL_VECTOR, used_vectors);
+#else
set_bit(SYSCALL_VECTOR, used_vectors);
#endif
/*