diff --git a/arch/um/kernel/skas/uaccess.c b/arch/um/kernel/skas/uaccess.c
index f7da9d0..7519528 100644
--- a/arch/um/kernel/skas/uaccess.c
+++ b/arch/um/kernel/skas/uaccess.c
@@ -29,9 +29,12 @@
 	if(IS_ERR(phys) || (is_write && !pte_write(pte))){
 		err = handle_page_fault(virt, 0, is_write, 1, &dummy_code);
 		if(err)
-			return(0);
+			return(-1UL);
 		phys = um_virt_to_phys(current, virt, NULL);
 	}
+        if(IS_ERR(phys))
+                phys = (void *) -1;
+
 	return((unsigned long) phys);
 }
 
@@ -42,7 +45,7 @@
 	int n;
 
 	addr = maybe_map(addr, is_write);
-	if(addr == -1)
+	if(addr == -1UL)
 		return(-1);
 
 	page = phys_to_page(addr);
diff --git a/arch/um/kernel/syscall_kern.c b/arch/um/kernel/syscall_kern.c
index 42731e0..b7a5525 100644
--- a/arch/um/kernel/syscall_kern.c
+++ b/arch/um/kernel/syscall_kern.c
@@ -17,7 +17,6 @@
 #include "linux/utime.h"
 #include "asm/mman.h"
 #include "asm/uaccess.h"
-#include "asm/ipc.h"
 #include "kern_util.h"
 #include "user_util.h"
 #include "sysdep/syscalls.h"
diff --git a/arch/um/kernel/trap_kern.c b/arch/um/kernel/trap_kern.c
index 54e2ec3..5fca2c6 100644
--- a/arch/um/kernel/trap_kern.c
+++ b/arch/um/kernel/trap_kern.c
@@ -48,7 +48,7 @@
 		goto good_area;
 	else if(!(vma->vm_flags & VM_GROWSDOWN)) 
 		goto out;
-	else if(!ARCH_IS_STACKGROW(address))
+	else if(is_user && !ARCH_IS_STACKGROW(address))
 		goto out;
 	else if(expand_stack(vma, address)) 
 		goto out;
diff --git a/arch/um/sys-x86_64/signal.c b/arch/um/sys-x86_64/signal.c
index b740177..73a7926 100644
--- a/arch/um/sys-x86_64/signal.c
+++ b/arch/um/sys-x86_64/signal.c
@@ -168,7 +168,7 @@
 
 	frame = (struct rt_sigframe __user *)
 		round_down(stack_top - sizeof(struct rt_sigframe), 16) - 8;
-	frame -= 128;
+	((unsigned char *) frame) -= 128;
 
 	if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate)))
 		goto out;
diff --git a/arch/um/sys-x86_64/syscalls.c b/arch/um/sys-x86_64/syscalls.c
index 2a575ef..dd99146 100644
--- a/arch/um/sys-x86_64/syscalls.c
+++ b/arch/um/sys-x86_64/syscalls.c
@@ -44,6 +44,8 @@
 #ifdef CONFIG_MODE_SKAS
 extern int userspace_pid[];
 
+#include "skas_ptrace.h"
+
 long sys_modify_ldt_skas(int func, void *ptr, unsigned long bytecount)
 {
 	struct ptrace_ldt ldt;