Fix for the panic("vm_thread_new: kstack allocation failed") and

silent NULL pointer dereference in the i386 and sparc64 pmap_pinit()
when the kmem_alloc_nofault() failed to allocate address space. Both
functions now return error instead of panicing or dereferencing NULL.

As consequence, vmspace_exec() and vmspace_unshare() returns the errno
int. struct vmspace arg was added to vm_forkproc() to avoid dealing
with failed allocation when most of the fork1() job is already done.

The kernel stack for the thread is now set up in the thread_alloc(),
that itself may return NULL. Also, allocation of the first process
thread is performed in the fork1() to properly deal with stack
allocation failure. proc_linkup() is separated into proc_linkup()
called from fork1(), and proc_linkup0(), that is used to set up the
kernel process (was known as swapper).

In collaboration with:	Peter Holm
Reviewed by:	jhb

1 files changed, 1 insertions, 0 deletions

diff --git a/sys/sys/signalvar.h b/sys/sys/signalvar.h
index e78358c..dc09226 100644
--- a/sys/sys/signalvar.h
+++ b/sys/sys/signalvar.h
@@ -299,6 +299,7 @@ struct mtx;
 
 extern int sugid_coredump;	/* Sysctl variable kern.sugid_coredump */
 extern struct mtx	sigio_lock;
+extern int kern_logsigexit;	/* Sysctl variable kern.logsigexit */
 
 /*
  * Lock the pointers for a sigio object in the underlying objects of