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>
This commit is contained in:
Roman Zippel 2008-05-05 21:25:48 +02:00 committed by Linus Torvalds
parent 4933d07531
commit 3b17f136bf
1 changed files with 14 additions and 3 deletions

View File

@ -468,15 +468,26 @@ static inline void access_error040(struct frame *fp)
* (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);