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Diffstat (limited to 'arch/x86_64/kernel/traps.c')
-rw-r--r--arch/x86_64/kernel/traps.c164
1 files changed, 101 insertions, 63 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index bf337f49318..8bb0aeda78b 100644
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -70,7 +70,6 @@ asmlinkage void reserved(void);
asmlinkage void alignment_check(void);
asmlinkage void machine_check(void);
asmlinkage void spurious_interrupt_bug(void);
-asmlinkage void call_debug(void);
struct notifier_block *die_chain;
static DEFINE_SPINLOCK(die_notifier_lock);
@@ -121,19 +120,31 @@ int printk_address(unsigned long address)
static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
unsigned *usedp, const char **idp)
{
- static const char ids[N_EXCEPTION_STACKS][8] = {
+ static char ids[][8] = {
[DEBUG_STACK - 1] = "#DB",
[NMI_STACK - 1] = "NMI",
[DOUBLEFAULT_STACK - 1] = "#DF",
[STACKFAULT_STACK - 1] = "#SS",
[MCE_STACK - 1] = "#MC",
+#if DEBUG_STKSZ > EXCEPTION_STKSZ
+ [N_EXCEPTION_STACKS ... N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]"
+#endif
};
unsigned k;
for (k = 0; k < N_EXCEPTION_STACKS; k++) {
unsigned long end;
- end = per_cpu(init_tss, cpu).ist[k];
+ switch (k + 1) {
+#if DEBUG_STKSZ > EXCEPTION_STKSZ
+ case DEBUG_STACK:
+ end = cpu_pda(cpu)->debugstack + DEBUG_STKSZ;
+ break;
+#endif
+ default:
+ end = per_cpu(init_tss, cpu).ist[k];
+ break;
+ }
if (stack >= end)
continue;
if (stack >= end - EXCEPTION_STKSZ) {
@@ -143,6 +154,22 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
*idp = ids[k];
return (unsigned long *)end;
}
+#if DEBUG_STKSZ > EXCEPTION_STKSZ
+ if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) {
+ unsigned j = N_EXCEPTION_STACKS - 1;
+
+ do {
+ ++j;
+ end -= EXCEPTION_STKSZ;
+ ids[j][4] = '1' + (j - N_EXCEPTION_STACKS);
+ } while (stack < end - EXCEPTION_STKSZ);
+ if (*usedp & (1U << j))
+ break;
+ *usedp |= 1U << j;
+ *idp = ids[j];
+ return (unsigned long *)end;
+ }
+#endif
}
return NULL;
}
@@ -156,9 +183,8 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
void show_trace(unsigned long *stack)
{
- unsigned long addr;
const unsigned cpu = safe_smp_processor_id();
- unsigned long *irqstack_end = (unsigned long *)cpu_pda[cpu].irqstackptr;
+ unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr;
int i;
unsigned used = 0;
@@ -166,8 +192,14 @@ void show_trace(unsigned long *stack)
#define HANDLE_STACK(cond) \
do while (cond) { \
- addr = *stack++; \
+ unsigned long addr = *stack++; \
if (kernel_text_address(addr)) { \
+ if (i > 50) { \
+ printk("\n "); \
+ i = 0; \
+ } \
+ else \
+ i += printk(" "); \
/* \
* If the address is either in the text segment of the \
* kernel, or in the region which contains vmalloc'ed \
@@ -177,25 +209,19 @@ void show_trace(unsigned long *stack)
* out the call path that was taken. \
*/ \
i += printk_address(addr); \
- if (i > 50) { \
- printk("\n "); \
- i = 0; \
- } \
- else \
- i += printk(" "); \
} \
} while (0)
- for(i = 0; ; ) {
+ for(i = 11; ; ) {
const char *id;
unsigned long *estack_end;
estack_end = in_exception_stack(cpu, (unsigned long)stack,
&used, &id);
if (estack_end) {
- i += printk(" <%s> ", id);
+ i += printk(" <%s>", id);
HANDLE_STACK (stack < estack_end);
- i += printk(" <EOE> ");
+ i += printk(" <EOE>");
stack = (unsigned long *) estack_end[-2];
continue;
}
@@ -205,11 +231,11 @@ void show_trace(unsigned long *stack)
(IRQSTACKSIZE - 64) / sizeof(*irqstack);
if (stack >= irqstack && stack < irqstack_end) {
- i += printk(" <IRQ> ");
+ i += printk(" <IRQ>");
HANDLE_STACK (stack < irqstack_end);
stack = (unsigned long *) (irqstack_end[-1]);
irqstack_end = NULL;
- i += printk(" <EOI> ");
+ i += printk(" <EOI>");
continue;
}
}
@@ -226,8 +252,8 @@ void show_stack(struct task_struct *tsk, unsigned long * rsp)
unsigned long *stack;
int i;
const int cpu = safe_smp_processor_id();
- unsigned long *irqstack_end = (unsigned long *) (cpu_pda[cpu].irqstackptr);
- unsigned long *irqstack = (unsigned long *) (cpu_pda[cpu].irqstackptr - IRQSTACKSIZE);
+ unsigned long *irqstack_end = (unsigned long *) (cpu_pda(cpu)->irqstackptr);
+ unsigned long *irqstack = (unsigned long *) (cpu_pda(cpu)->irqstackptr - IRQSTACKSIZE);
// debugging aid: "show_stack(NULL, NULL);" prints the
// back trace for this cpu.
@@ -275,14 +301,14 @@ void show_registers(struct pt_regs *regs)
int in_kernel = !user_mode(regs);
unsigned long rsp;
const int cpu = safe_smp_processor_id();
- struct task_struct *cur = cpu_pda[cpu].pcurrent;
+ struct task_struct *cur = cpu_pda(cpu)->pcurrent;
rsp = regs->rsp;
printk("CPU %d ", cpu);
__show_regs(regs);
printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
- cur->comm, cur->pid, cur->thread_info, cur);
+ cur->comm, cur->pid, task_thread_info(cur), cur);
/*
* When in-kernel, we also print out the stack and code at the
@@ -314,20 +340,26 @@ bad:
void handle_BUG(struct pt_regs *regs)
{
struct bug_frame f;
- char tmp;
+ long len;
+ const char *prefix = "";
if (user_mode(regs))
return;
- if (__copy_from_user(&f, (struct bug_frame *) regs->rip,
+ if (__copy_from_user(&f, (const void __user *) regs->rip,
sizeof(struct bug_frame)))
return;
if (f.filename >= 0 ||
f.ud2[0] != 0x0f || f.ud2[1] != 0x0b)
return;
- if (__get_user(tmp, (char *)(long)f.filename))
+ len = __strnlen_user((char *)(long)f.filename, PATH_MAX) - 1;
+ if (len < 0 || len >= PATH_MAX)
f.filename = (int)(long)"unmapped filename";
+ else if (len > 50) {
+ f.filename += len - 50;
+ prefix = "...";
+ }
printk("----------- [cut here ] --------- [please bite here ] ---------\n");
- printk(KERN_ALERT "Kernel BUG at %.50s:%d\n", (char *)(long)f.filename, f.line);
+ printk(KERN_ALERT "Kernel BUG at %s%.50s:%d\n", prefix, (char *)(long)f.filename, f.line);
}
#ifdef CONFIG_BUG
@@ -382,7 +414,7 @@ void __die(const char * str, struct pt_regs * regs, long err)
printk("DEBUG_PAGEALLOC");
#endif
printk("\n");
- notify_die(DIE_OOPS, (char *)str, regs, err, 255, SIGSEGV);
+ notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
show_registers(regs);
/* Executive summary in case the oops scrolled away */
printk(KERN_ALERT "RIP ");
@@ -399,11 +431,6 @@ void die(const char * str, struct pt_regs * regs, long err)
oops_end(flags);
do_exit(SIGSEGV);
}
-static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err)
-{
- if (!(regs->eflags & VM_MASK) && (regs->cs == __KERNEL_CS))
- die(str, regs, err);
-}
void die_nmi(char *str, struct pt_regs *regs)
{
@@ -426,19 +453,20 @@ static void __kprobes do_trap(int trapnr, int signr, char *str,
struct pt_regs * regs, long error_code,
siginfo_t *info)
{
+ struct task_struct *tsk = current;
+
conditional_sti(regs);
- if (user_mode(regs)) {
- struct task_struct *tsk = current;
+ tsk->thread.error_code = error_code;
+ tsk->thread.trap_no = trapnr;
+ if (user_mode(regs)) {
if (exception_trace && unhandled_signal(tsk, signr))
printk(KERN_INFO
"%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n",
tsk->comm, tsk->pid, str,
regs->rip,regs->rsp,error_code);
- tsk->thread.error_code = error_code;
- tsk->thread.trap_no = trapnr;
if (info)
force_sig_info(signr, info, tsk);
else
@@ -485,7 +513,7 @@ asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
DO_ERROR_INFO( 0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->rip)
DO_ERROR( 4, SIGSEGV, "overflow", overflow)
DO_ERROR( 5, SIGSEGV, "bounds", bounds)
-DO_ERROR_INFO( 6, SIGILL, "invalid operand", invalid_op, ILL_ILLOPN, regs->rip)
+DO_ERROR_INFO( 6, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, regs->rip)
DO_ERROR( 7, SIGSEGV, "device not available", device_not_available)
DO_ERROR( 9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun)
DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
@@ -493,24 +521,41 @@ DO_ERROR(11, SIGBUS, "segment not present", segment_not_present)
DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
DO_ERROR(18, SIGSEGV, "reserved", reserved)
DO_ERROR(12, SIGBUS, "stack segment", stack_segment)
-DO_ERROR( 8, SIGSEGV, "double fault", double_fault)
+
+asmlinkage void do_double_fault(struct pt_regs * regs, long error_code)
+{
+ static const char str[] = "double fault";
+ struct task_struct *tsk = current;
+
+ /* Return not checked because double check cannot be ignored */
+ notify_die(DIE_TRAP, str, regs, error_code, 8, SIGSEGV);
+
+ 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). */
+ for (;;)
+ die(str, regs, error_code);
+}
asmlinkage void __kprobes do_general_protection(struct pt_regs * regs,
long error_code)
{
+ struct task_struct *tsk = current;
+
conditional_sti(regs);
- if (user_mode(regs)) {
- struct task_struct *tsk = current;
+ tsk->thread.error_code = error_code;
+ tsk->thread.trap_no = 13;
+ if (user_mode(regs)) {
if (exception_trace && unhandled_signal(tsk, SIGSEGV))
printk(KERN_INFO
"%s[%d] general protection rip:%lx rsp:%lx error:%lx\n",
tsk->comm, tsk->pid,
regs->rip,regs->rsp,error_code);
- tsk->thread.error_code = error_code;
- tsk->thread.trap_no = 13;
force_sig(SIGSEGV, tsk);
return;
}
@@ -573,7 +618,7 @@ asmlinkage void default_do_nmi(struct pt_regs *regs)
reason = get_nmi_reason();
if (!(reason & 0xc0)) {
- if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 0, SIGINT)
+ if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT)
== NOTIFY_STOP)
return;
#ifdef CONFIG_X86_LOCAL_APIC
@@ -589,7 +634,7 @@ asmlinkage void default_do_nmi(struct pt_regs *regs)
unknown_nmi_error(reason, regs);
return;
}
- if (notify_die(DIE_NMI, "nmi", regs, reason, 0, SIGINT) == NOTIFY_STOP)
+ if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
return;
/* AK: following checks seem to be broken on modern chipsets. FIXME */
@@ -600,6 +645,7 @@ asmlinkage void default_do_nmi(struct pt_regs *regs)
io_check_error(reason, regs);
}
+/* runs on IST stack. */
asmlinkage void __kprobes do_int3(struct pt_regs * regs, long error_code)
{
if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) == NOTIFY_STOP) {
@@ -620,7 +666,7 @@ asmlinkage struct pt_regs *sync_regs(struct pt_regs *eregs)
;
/* Exception from user space */
else if (user_mode(eregs))
- regs = ((struct pt_regs *)current->thread.rsp0) - 1;
+ regs = task_pt_regs(current);
/* Exception from kernel and interrupts are enabled. Move to
kernel process stack. */
else if (eregs->eflags & X86_EFLAGS_IF)
@@ -684,11 +730,9 @@ asmlinkage void __kprobes do_debug(struct pt_regs * regs,
info.si_signo = SIGTRAP;
info.si_errno = 0;
info.si_code = TRAP_BRKPT;
- if (!user_mode(regs))
- goto clear_dr7;
+ info.si_addr = user_mode(regs) ? (void __user *)regs->rip : NULL;
+ force_sig_info(SIGTRAP, &info, tsk);
- info.si_addr = (void __user *)regs->rip;
- force_sig_info(SIGTRAP, &info, tsk);
clear_dr7:
set_debugreg(0UL, 7);
return;
@@ -698,7 +742,7 @@ clear_TF_reenable:
regs->eflags &= ~TF_MASK;
}
-static int kernel_math_error(struct pt_regs *regs, char *str)
+static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
{
const struct exception_table_entry *fixup;
fixup = search_exception_tables(regs->rip);
@@ -706,8 +750,9 @@ static int kernel_math_error(struct pt_regs *regs, char *str)
regs->rip = fixup->fixup;
return 1;
}
- notify_die(DIE_GPF, str, regs, 0, 16, SIGFPE);
+ notify_die(DIE_GPF, str, regs, 0, trapnr, SIGFPE);
/* Illegal floating point operation in the kernel */
+ current->thread.trap_no = trapnr;
die(str, regs, 0);
return 0;
}
@@ -726,7 +771,7 @@ asmlinkage void do_coprocessor_error(struct pt_regs *regs)
conditional_sti(regs);
if (!user_mode(regs) &&
- kernel_math_error(regs, "kernel x87 math error"))
+ kernel_math_error(regs, "kernel x87 math error", 16))
return;
/*
@@ -795,7 +840,7 @@ asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs)
conditional_sti(regs);
if (!user_mode(regs) &&
- kernel_math_error(regs, "kernel simd math error"))
+ kernel_math_error(regs, "kernel simd math error", 19))
return;
/*
@@ -867,12 +912,7 @@ asmlinkage void math_state_restore(void)
if (!used_math())
init_fpu(me);
restore_fpu_checking(&me->thread.i387.fxsave);
- me->thread_info->status |= TS_USEDFPU;
-}
-
-void do_call_debug(struct pt_regs *regs)
-{
- notify_die(DIE_CALL, "debug call", regs, 0, 255, SIGINT);
+ task_thread_info(me)->status |= TS_USEDFPU;
}
void __init trap_init(void)
@@ -880,9 +920,9 @@ void __init trap_init(void)
set_intr_gate(0,&divide_error);
set_intr_gate_ist(1,&debug,DEBUG_STACK);
set_intr_gate_ist(2,&nmi,NMI_STACK);
- set_system_gate(3,&int3);
- set_system_gate(4,&overflow); /* int4-5 can be called from all */
- set_system_gate(5,&bounds);
+ set_system_gate_ist(3,&int3,DEBUG_STACK); /* int3 can be called from all */
+ set_system_gate(4,&overflow); /* int4 can be called from all */
+ set_intr_gate(5,&bounds);
set_intr_gate(6,&invalid_op);
set_intr_gate(7,&device_not_available);
set_intr_gate_ist(8,&double_fault, DOUBLEFAULT_STACK);
@@ -904,8 +944,6 @@ void __init trap_init(void)
set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
#endif
- set_intr_gate(KDB_VECTOR, call_debug);
-
/*
* Should be a barrier for any external CPU state.
*/
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-09 11:21:15 +0000