m68k: Allow all kernel traps to be handled via exception fixups

This will be needed by the ARAnyM Native Feature initialization code.
Also document that the VEC_TRACE check is needed for 68020/30.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c
index cd802d49f7e909dd8e15e89676a6bf78dec291b3..4022bbc288782357fa339c17e2254d6462ca6327 100644 (file)
--- a/arch/m68k/kernel/traps.c
+++ b/arch/m68k/kernel/traps.c
@@ -58,6 +58,7 @@ asm(".text\n"
 /*
  * this must be called very early as the kernel might
  * use some instruction that are emulated on the 060
+ * and so we're prepared for early probe attempts (e.g. nf_init).
  */
 void __init base_trap_init(void)
 {
@@ -78,6 +79,7 @@ void __init base_trap_init(void)
        }
 
        vectors[VEC_BUSERR] = buserr;
+       vectors[VEC_ILLEGAL] = trap;
        vectors[VEC_SYS] = system_call;
 }
 
@@ -1055,9 +1057,11 @@ asmlinkage void trap_c(struct frame *fp)
        siginfo_t info;
 
        if (fp->ptregs.sr & PS_S) {
-               if ((fp->ptregs.vector >> 2) == VEC_TRACE) {
-                       /* traced a trapping instruction */
-               } else
+               if (fp->ptregs.vector == VEC_TRACE << 2) {
+                       /* traced a trapping instruction on a 68020/30,
+                        * real exception will be executed afterwards.
+                        */
+               } else if (!handle_kernel_fault(&fp->ptregs))
                        bad_super_trap(fp);
                return;
        }