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, 1 deletions

diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index 3b213a6..239c420 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -102,7 +102,7 @@ static uma_zone_t	ksiginfo_zone = NULL;
 struct filterops sig_filtops =
 	{ 0, filt_sigattach, filt_sigdetach, filt_signal };
 
-static int	kern_logsigexit = 1;
+int	kern_logsigexit = 1;
 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW, 
     &kern_logsigexit, 0, 
     "Log processes quitting on abnormal signals to syslog(3)");