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Diffstat (limited to 'arch/x86/mm/fault.c')
-rw-r--r--arch/x86/mm/fault.c66
1 files changed, 45 insertions, 21 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 3aaeffcfd67a..9ff85bb8dd69 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -20,6 +20,9 @@
#include <asm/kmemcheck.h> /* kmemcheck_*(), ... */
#include <asm/fixmap.h> /* VSYSCALL_START */
+#define CREATE_TRACE_POINTS
+#include <asm/trace/exceptions.h>
+
/*
* Page fault error code bits:
*
@@ -51,7 +54,7 @@ kmmio_fault(struct pt_regs *regs, unsigned long addr)
return 0;
}
-static inline int __kprobes notify_page_fault(struct pt_regs *regs)
+static inline int __kprobes kprobes_fault(struct pt_regs *regs)
{
int ret = 0;
@@ -596,7 +599,7 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code,
printk(KERN_CONT " at %p\n", (void *) address);
printk(KERN_ALERT "IP:");
- printk_address(regs->ip, 1);
+ printk_address(regs->ip);
dump_pagetable(address);
}
@@ -1048,7 +1051,7 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code)
return;
/* kprobes don't want to hook the spurious faults: */
- if (notify_page_fault(regs))
+ if (kprobes_fault(regs))
return;
/*
* Don't take the mm semaphore here. If we fixup a prefetch
@@ -1060,23 +1063,8 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code)
}
/* kprobes don't want to hook the spurious faults: */
- if (unlikely(notify_page_fault(regs)))
+ if (unlikely(kprobes_fault(regs)))
return;
- /*
- * It's safe to allow irq's after cr2 has been saved and the
- * vmalloc fault has been handled.
- *
- * User-mode registers count as a user access even for any
- * potential system fault or CPU buglet:
- */
- if (user_mode_vm(regs)) {
- local_irq_enable();
- error_code |= PF_USER;
- flags |= FAULT_FLAG_USER;
- } else {
- if (regs->flags & X86_EFLAGS_IF)
- local_irq_enable();
- }
if (unlikely(error_code & PF_RSVD))
pgtable_bad(regs, error_code, address);
@@ -1088,8 +1076,6 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code)
}
}
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
-
/*
* If we're in an interrupt, have no user context or are running
* in an atomic region then we must not take the fault:
@@ -1099,6 +1085,24 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code)
return;
}
+ /*
+ * It's safe to allow irq's after cr2 has been saved and the
+ * vmalloc fault has been handled.
+ *
+ * User-mode registers count as a user access even for any
+ * potential system fault or CPU buglet:
+ */
+ if (user_mode_vm(regs)) {
+ local_irq_enable();
+ error_code |= PF_USER;
+ flags |= FAULT_FLAG_USER;
+ } else {
+ if (regs->flags & X86_EFLAGS_IF)
+ local_irq_enable();
+ }
+
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
+
if (error_code & PF_WRITE)
flags |= FAULT_FLAG_WRITE;
@@ -1231,3 +1235,23 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code)
__do_page_fault(regs, error_code);
exception_exit(prev_state);
}
+
+static void trace_page_fault_entries(struct pt_regs *regs,
+ unsigned long error_code)
+{
+ if (user_mode(regs))
+ trace_page_fault_user(read_cr2(), regs, error_code);
+ else
+ trace_page_fault_kernel(read_cr2(), regs, error_code);
+}
+
+dotraplinkage void __kprobes
+trace_do_page_fault(struct pt_regs *regs, unsigned long error_code)
+{
+ enum ctx_state prev_state;
+
+ prev_state = exception_enter();
+ trace_page_fault_entries(regs, error_code);
+ __do_page_fault(regs, error_code);
+ exception_exit(prev_state);
+}