x86: add is_errata100 helper to fault_32|64.c

Further towards unifying these files, add another helper
in same spirit as is_errata93.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/mm/fault_32.c b/arch/x86/mm/fault_32.c
index 75ae8c4..0bd2417 100644 (file)
--- a/arch/x86/mm/fault_32.c
+++ b/arch/x86/mm/fault_32.c
@@ -286,6 +286,22 @@ static int is_errata93(struct pt_regs *regs, unsigned long address)
        return 0;
 }
 
+/*
+ * Work around K8 erratum #100 K8 in compat mode occasionally jumps to illegal
+ * addresses >4GB.  We catch this in the page fault handler because these
+ * addresses are not reachable. Just detect this case and return.  Any code
+ * segment in LDT is compatibility mode.
+ */
+static int is_errata100(struct pt_regs *regs, unsigned long address)
+{
+#ifdef CONFIG_X86_64
+       if ((regs->cs == __USER32_CS || (regs->cs & (1<<2))) &&
+           (address >> 32))
+               return 1;
+#endif
+       return 0;
+}
+
 void do_invalid_op(struct pt_regs *, unsigned long);
 
 static int is_f00f_bug(struct pt_regs *regs, unsigned long address)
@@ -566,6 +582,9 @@ bad_area_nosemaphore:
                if (is_prefetch(regs, address, error_code))
                        return;
 
+               if (is_errata100(regs, address))
+                       return;
+
                if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
                    printk_ratelimit()) {
                        printk(

diff --git a/arch/x86/mm/fault_64.c b/arch/x86/mm/fault_64.c
index df13487..ccbb8e3 100644 (file)
--- a/arch/x86/mm/fault_64.c
+++ b/arch/x86/mm/fault_64.c
@@ -256,6 +256,22 @@ static int is_errata93(struct pt_regs *regs, unsigned long address)
        return 0;
 }
 
+/*
+ * Work around K8 erratum #100 K8 in compat mode occasionally jumps to illegal
+ * addresses >4GB.  We catch this in the page fault handler because these
+ * addresses are not reachable. Just detect this case and return.  Any code
+ * segment in LDT is compatibility mode.
+ */
+static int is_errata100(struct pt_regs *regs, unsigned long address)
+{
+#ifdef CONFIG_X86_64
+       if ((regs->cs == __USER32_CS || (regs->cs & (1<<2))) &&
+           (address >> 32))
+               return 1;
+#endif
+       return 0;
+}
+
 void do_invalid_op(struct pt_regs *, unsigned long);
 
 static int is_f00f_bug(struct pt_regs *regs, unsigned long address)
@@ -568,14 +584,7 @@ bad_area_nosemaphore:
                if (is_prefetch(regs, address, error_code))
                        return;
 
-               /* Work around K8 erratum #100 K8 in compat mode
-                  occasionally jumps to illegal addresses >4GB.  We
-                  catch this here in the page fault handler because
-                  these addresses are not reachable. Just detect this
-                  case and return.  Any code segment in LDT is
-                  compatibility mode. */
-               if ((regs->cs == __USER32_CS || (regs->cs & (1<<2))) &&
-                   (address >> 32))
+               if (is_errata100(regs, address))
                        return;
 
                if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&