x86: Merge kernel_math_error() into math_error()

Clean up the kernel exception handling and make it more similar to
the other traps.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1269176446-2489-4-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 16 insertions, 28 deletions

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index a472992cecdc..53ba86fc5dd8 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -576,20 +576,6 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)
         return;
 }
 
-#ifdef CONFIG_X86_64
-static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
-{
-        if (fixup_exception(regs))
-                return 1;
-
-        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;
-}
-#endif
-
 /*
  * Note that we play around with the 'TS' bit in an attempt to get
  * the correct behaviour even in the presence of the asynchronous
@@ -597,14 +583,28 @@ static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
  */
 void math_error(struct pt_regs *regs, int error_code, int trapnr)
 {
-        struct task_struct *task;
+        struct task_struct *task = current;
         siginfo_t info;
         unsigned short err;
+        char *str = (trapnr == 16) ? "fpu exception" : "simd exception";
+
+        if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, SIGFPE) == NOTIFY_STOP)
+                return;
+        conditional_sti(regs);
+
+        if (!user_mode_vm(regs))
+        {
+                if (!fixup_exception(regs)) {
+                        task->thread.error_code = error_code;
+                        task->thread.trap_no = trapnr;
+                        die(str, regs, error_code);
+                }
+                return;
+        }
 
         /*
          * Save the info for the exception handler and clear the error.
          */
-        task = current;
         save_init_fpu(task);
         task->thread.trap_no = trapnr;
         task->thread.error_code = error_code;
@@ -665,14 +665,8 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr)
 
 dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
 {
-        conditional_sti(regs);
-
 #ifdef CONFIG_X86_32
         ignore_fpu_irq = 1;
-#else
-        if (!user_mode(regs) &&
-            kernel_math_error(regs, "kernel x87 math error", 16))
-                return;
 #endif
 
         math_error(regs, error_code, 16);
@@ -681,14 +675,8 @@ dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
 dotraplinkage void
 do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
 {
-        conditional_sti(regs);
-
 #ifdef CONFIG_X86_32
         ignore_fpu_irq = 1;
-#else
-        if (!user_mode(regs) &&
-                        kernel_math_error(regs, "kernel simd math error", 19))
-                return;
 #endif
 
         math_error(regs, error_code, 19);