[PATCH] ppc32: Kill init on unhandled synchronous signals
This is a patch that I have had in my tree for ages. If init causes
an exception that raises a signal, such as a SIGSEGV, SIGILL or
SIGFPE, and it hasn't registered a handler for it, we don't deliver
the signal, since init doesn't get any signals that it doesn't have a
handler for. But that means that we just return to userland and
generate the same exception again immediately. With this patch we
print a message and kill init in this situation.
This is very useful when you have a bug in the kernel that means that
init doesn't get as far as executing its first instruction. :)
Without this patch the system hangs when it gets to starting the
userland init; with it you at least get a message giving you a clue
about what has gone wrong.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/ppc/mm/fault.c b/arch/ppc/mm/fault.c
index 57d9930..ee5e9f2 100644
--- a/arch/ppc/mm/fault.c
+++ b/arch/ppc/mm/fault.c
@@ -278,11 +278,7 @@
/* User mode accesses cause a SIGSEGV */
if (user_mode(regs)) {
- info.si_signo = SIGSEGV;
- info.si_errno = 0;
- info.si_code = code;
- info.si_addr = (void __user *) address;
- force_sig_info(SIGSEGV, &info, current);
+ _exception(SIGSEGV, regs, code, address);
return 0;
}