x86: unify extable_{32|64}.c

Introduce fixup_exception() on 64-bit and use it in kprobes to
eliminate an #ifdef.

Only 64-bit needs search_extable() due to a stepping bug.

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/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index 8de82c8cedd6a9f03f2dfa1d280a4154e69dbd1e..7848bf74e2abe087967714af9ccf76891e8a1952 100644 (file)
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -904,19 +904,9 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
                 * In case the user-specified fault handler returned
                 * zero, try to fix up.
                 */
-#ifdef CONFIG_X86_64
-               {
-                       const struct exception_table_entry *fixup;
-                       fixup = search_exception_tables(regs->ip);
-                       if (fixup) {
-                               regs->ip = fixup->fixup;
-                               return 1;
-                       }
-               }
-#else
                if (fixup_exception(regs))
                        return 1;
-#endif
+
                /*
                 * fixup routine could not handle it,
                 * Let do_page_fault() fix it.

diff --git a/arch/x86/mm/Makefile_32 b/arch/x86/mm/Makefile_32
index a01aca79dc69ce855fdf80b7256430f1c98d583f..6a5e981981f7cc7ddd5760ecbabfbb383b1a83ad 100644 (file)
--- a/arch/x86/mm/Makefile_32
+++ b/arch/x86/mm/Makefile_32
@@ -2,7 +2,7 @@
 # Makefile for the linux i386-specific parts of the memory manager.
 #
 
-obj-y  := init_32.o pgtable_32.o fault_32.o ioremap_32.o extable_32.o pageattr_32.o mmap.o
+obj-y  := init_32.o pgtable_32.o fault_32.o ioremap_32.o extable.o pageattr_32.o mmap.o
 
 obj-$(CONFIG_NUMA) += discontig_32.o
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o

diff --git a/arch/x86/mm/Makefile_64 b/arch/x86/mm/Makefile_64
index b5a74486c3aa1acc197b2a54491199bd2905ba32..09c997fe5856d9609244b725275daa39bdcc2755 100644 (file)
--- a/arch/x86/mm/Makefile_64
+++ b/arch/x86/mm/Makefile_64
@@ -2,7 +2,7 @@
 # Makefile for the linux x86_64-specific parts of the memory manager.
 #
 
-obj-y   := init_64.o fault_64.o ioremap_64.o extable_64.o pageattr_64.o mmap.o
+obj-y   := init_64.o fault_64.o ioremap_64.o extable.o pageattr_64.o mmap.o
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
 obj-$(CONFIG_NUMA) += numa_64.o
 obj-$(CONFIG_K8_NUMA) += k8topology_64.o

diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
new file mode 100644 (file)
index 0000000..7e8db53
--- /dev/null
+++ b/arch/x86/mm/extable.c
@@ -0,0 +1,62 @@
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <asm/uaccess.h>
+
+
+int fixup_exception(struct pt_regs *regs)
+{
+       const struct exception_table_entry *fixup;
+
+#ifdef CONFIG_PNPBIOS
+       if (unlikely(SEGMENT_IS_PNP_CODE(regs->cs))) {
+               extern u32 pnp_bios_fault_eip, pnp_bios_fault_esp;
+               extern u32 pnp_bios_is_utter_crap;
+               pnp_bios_is_utter_crap = 1;
+               printk(KERN_CRIT "PNPBIOS fault.. attempting recovery.\n");
+               __asm__ volatile(
+                       "movl %0, %%esp\n\t"
+                       "jmp *%1\n\t"
+                       : : "g" (pnp_bios_fault_esp), "g" (pnp_bios_fault_eip));
+               panic("do_trap: can't hit this");
+       }
+#endif
+
+       fixup = search_exception_tables(regs->ip);
+       if (fixup) {
+               regs->ip = fixup->fixup;
+               return 1;
+       }
+
+       return 0;
+}
+
+#ifdef CONFIG_X86_64
+/*
+ * Need to defined our own search_extable on X86_64 to work around
+ * a B stepping K8 bug.
+ */
+const struct exception_table_entry *
+search_extable(const struct exception_table_entry *first,
+              const struct exception_table_entry *last,
+              unsigned long value)
+{
+       /* B stepping K8 bug */
+       if ((value >> 32) == 0)
+               value |= 0xffffffffUL << 32;
+
+       while (first <= last) {
+               const struct exception_table_entry *mid;
+               long diff;
+
+               mid = (last - first) / 2 + first;
+               diff = mid->insn - value;
+               if (diff == 0)
+                       return mid;
+               else if (diff < 0)
+                       first = mid+1;
+               else
+                       last = mid-1;
+       }
+       return NULL;
+}
+#endif

diff --git a/arch/x86/mm/extable_32.c b/arch/x86/mm/extable_32.c
deleted file mode 100644 (file)
index 4168546..0000000
--- a/arch/x86/mm/extable_32.c
+++ /dev/null
@@ -1,35 +0,0 @@
-/*
- * linux/arch/i386/mm/extable.c
- */
-
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <asm/uaccess.h>
-
-int fixup_exception(struct pt_regs *regs)
-{
-       const struct exception_table_entry *fixup;
-
-#ifdef CONFIG_PNPBIOS
-       if (unlikely(SEGMENT_IS_PNP_CODE(regs->cs)))
-       {
-               extern u32 pnp_bios_fault_eip, pnp_bios_fault_esp;
-               extern u32 pnp_bios_is_utter_crap;
-               pnp_bios_is_utter_crap = 1;
-               printk(KERN_CRIT "PNPBIOS fault.. attempting recovery.\n");
-               __asm__ volatile(
-                       "movl %0, %%esp\n\t"
-                       "jmp *%1\n\t"
-                       : : "g" (pnp_bios_fault_esp), "g" (pnp_bios_fault_eip));
-               panic("do_trap: can't hit this");
-       }
-#endif
-
-       fixup = search_exception_tables(regs->ip);
-       if (fixup) {
-               regs->ip = fixup->fixup;
-               return 1;
-       }
-
-       return 0;
-}

diff --git a/arch/x86/mm/extable_64.c b/arch/x86/mm/extable_64.c
deleted file mode 100644 (file)
index 79ac6e7..0000000
--- a/arch/x86/mm/extable_64.c
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * linux/arch/x86_64/mm/extable.c
- */
-
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/init.h>
-#include <asm/uaccess.h>
-
-/* Simple binary search */
-const struct exception_table_entry *
-search_extable(const struct exception_table_entry *first,
-              const struct exception_table_entry *last,
-              unsigned long value)
-{
-       /* Work around a B stepping K8 bug */
-       if ((value >> 32) == 0)
-               value |= 0xffffffffUL << 32; 
-
-        while (first <= last) {
-               const struct exception_table_entry *mid;
-               long diff;
-
-               mid = (last - first) / 2 + first;
-               diff = mid->insn - value;
-                if (diff == 0)
-                        return mid;
-                else if (diff < 0)
-                        first = mid+1;
-                else
-                        last = mid-1;
-        }
-        return NULL;
-}