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Diffstat (limited to 'arch/x86_64/kernel/traps.c')
-rw-r--r--arch/x86_64/kernel/traps.c55
1 files changed, 31 insertions, 24 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index 0d65b22f229c..a1641ffdffcf 100644
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -30,9 +30,9 @@
#include <linux/kprobes.h>
#include <linux/kexec.h>
#include <linux/unwind.h>
+#include <linux/uaccess.h>
#include <asm/system.h>
-#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/atomic.h>
#include <asm/debugreg.h>
@@ -108,7 +108,7 @@ static inline void preempt_conditional_cli(struct pt_regs *regs)
preempt_enable_no_resched();
}
-static int kstack_depth_to_print = 12;
+int kstack_depth_to_print = 12;
#ifdef CONFIG_STACK_UNWIND
static int call_trace = 1;
#else
@@ -225,16 +225,25 @@ static int dump_trace_unwind(struct unwind_frame_info *info, void *context)
{
struct ops_and_data *oad = (struct ops_and_data *)context;
int n = 0;
+ unsigned long sp = UNW_SP(info);
+ if (arch_unw_user_mode(info))
+ return -1;
while (unwind(info) == 0 && UNW_PC(info)) {
n++;
oad->ops->address(oad->data, UNW_PC(info));
if (arch_unw_user_mode(info))
break;
+ if ((sp & ~(PAGE_SIZE - 1)) == (UNW_SP(info) & ~(PAGE_SIZE - 1))
+ && sp > UNW_SP(info))
+ break;
+ sp = UNW_SP(info);
}
return n;
}
+#define MSG(txt) ops->warning(data, txt)
+
/*
* x86-64 can have upto three kernel stacks:
* process stack
@@ -248,11 +257,12 @@ static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
return p > t && p < t + THREAD_SIZE - 3;
}
-void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * stack,
+void dump_trace(struct task_struct *tsk, struct pt_regs *regs,
+ unsigned long *stack,
struct stacktrace_ops *ops, void *data)
{
- const unsigned cpu = smp_processor_id();
- unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr;
+ const unsigned cpu = get_cpu();
+ unsigned long *irqstack_end = (unsigned long*)cpu_pda(cpu)->irqstackptr;
unsigned used = 0;
struct thread_info *tinfo;
@@ -268,28 +278,30 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * s
if (unwind_init_frame_info(&info, tsk, regs) == 0)
unw_ret = dump_trace_unwind(&info, &oad);
} else if (tsk == current)
- unw_ret = unwind_init_running(&info, dump_trace_unwind, &oad);
+ unw_ret = unwind_init_running(&info, dump_trace_unwind,
+ &oad);
else {
if (unwind_init_blocked(&info, tsk) == 0)
unw_ret = dump_trace_unwind(&info, &oad);
}
if (unw_ret > 0) {
if (call_trace == 1 && !arch_unw_user_mode(&info)) {
- ops->warning_symbol(data, "DWARF2 unwinder stuck at %s\n",
+ ops->warning_symbol(data,
+ "DWARF2 unwinder stuck at %s",
UNW_PC(&info));
if ((long)UNW_SP(&info) < 0) {
- ops->warning(data, "Leftover inexact backtrace:\n");
+ MSG("Leftover inexact backtrace:");
stack = (unsigned long *)UNW_SP(&info);
if (!stack)
- return;
+ goto out;
} else
- ops->warning(data, "Full inexact backtrace again:\n");
+ MSG("Full inexact backtrace again:");
} else if (call_trace >= 1)
- return;
+ goto out;
else
- ops->warning(data, "Full inexact backtrace again:\n");
+ MSG("Full inexact backtrace again:");
} else
- ops->warning(data, "Inexact backtrace:\n");
+ MSG("Inexact backtrace:");
}
if (!stack) {
unsigned long dummy;
@@ -297,12 +309,6 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * s
if (tsk && tsk != current)
stack = (unsigned long *)tsk->thread.rsp;
}
- /*
- * Align the stack pointer on word boundary, later loops
- * rely on that (and corruption / debug info bugs can cause
- * unaligned values here):
- */
- stack = (unsigned long *)((unsigned long)stack & ~(sizeof(long)-1));
/*
* Print function call entries within a stack. 'cond' is the
@@ -312,9 +318,9 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * s
#define HANDLE_STACK(cond) \
do while (cond) { \
unsigned long addr = *stack++; \
- if (oops_in_progress ? \
- __kernel_text_address(addr) : \
- kernel_text_address(addr)) { \
+ /* Use unlocked access here because except for NMIs \
+ we should be already protected against module unloads */ \
+ if (__kernel_text_address(addr)) { \
/* \
* If the address is either in the text segment of the \
* kernel, or in the region which contains vmalloc'ed \
@@ -380,6 +386,8 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * s
tinfo = current_thread_info();
HANDLE_STACK (valid_stack_ptr(tinfo, stack));
#undef HANDLE_STACK
+out:
+ put_cpu();
}
EXPORT_SYMBOL(dump_trace);
@@ -786,8 +794,7 @@ mem_parity_error(unsigned char reason, struct pt_regs * regs)
{
printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x.\n",
reason);
- printk(KERN_EMERG "You probably have a hardware problem with your "
- "RAM chips\n");
+ printk(KERN_EMERG "You have some hardware problem, likely on the PCI bus.\n");
if (panic_on_unrecovered_nmi)
panic("NMI: Not continuing");