m68k: Handle 68040 bus faults
Fix 68040 bus fault handling, so the standard kernel exception handling
can be used for i/o probing.
Contrary to normal access faults there is nothing to fix, but at least
we have to disable writebacks to avoid recursive faults.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c
index fd4858e..75b8340 100644
--- a/arch/m68k/kernel/traps.c
+++ b/arch/m68k/kernel/traps.c
@@ -468,15 +468,26 @@
* (if do_page_fault didn't fix the mapping,
* the writeback won't do good)
*/
+disable_wb:
#ifdef DEBUG
printk(".. disabling wb2\n");
#endif
if (fp->un.fmt7.wb2a == fp->un.fmt7.faddr)
fp->un.fmt7.wb2s &= ~WBV_040;
+ if (fp->un.fmt7.wb3a == fp->un.fmt7.faddr)
+ fp->un.fmt7.wb3s &= ~WBV_040;
}
- } else if (send_fault_sig(&fp->ptregs) > 0) {
- printk("68040 access error, ssw=%x\n", ssw);
- trap_c(fp);
+ } else {
+ /* In case of a bus error we either kill the process or expect
+ * the kernel to catch the fault, which then is also responsible
+ * for cleaning up the mess.
+ */
+ current->thread.signo = SIGBUS;
+ current->thread.faddr = fp->un.fmt7.faddr;
+ if (send_fault_sig(&fp->ptregs) >= 0)
+ printk("68040 bus error (ssw=%x, faddr=%lx)\n", ssw,
+ fp->un.fmt7.faddr);
+ goto disable_wb;
}
do_040writebacks(fp);