25 files changed, 72 insertions, 76 deletions

diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index b3a21ba77cd2..354cc6b70530 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -44,7 +44,7 @@ config LOCKDEP_SUPPORT
 
 config STACKTRACE_SUPPORT
         bool
-        default y
+        default n
 
 config GENERIC_CALIBRATE_DELAY
         bool
diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c
index 7b8baf146acc..9fdfad649536 100644
--- a/arch/um/drivers/chan_kern.c
+++ b/arch/um/drivers/chan_kern.c
@@ -236,11 +236,11 @@ void free_irqs(void)
         struct chan *chan;
         LIST_HEAD(list);
         struct list_head *ele;
+        unsigned long flags;
 
-        spin_lock_irq(&irqs_to_free_lock);
+        spin_lock_irqsave(&irqs_to_free_lock, flags);
         list_splice_init(&irqs_to_free, &list);
-        INIT_LIST_HEAD(&irqs_to_free);
-        spin_unlock_irq(&irqs_to_free_lock);
+        spin_unlock_irqrestore(&irqs_to_free_lock, flags);
 
         list_for_each(ele, &list){
                 chan = list_entry(ele, struct chan, free_list);
@@ -255,13 +255,15 @@ void free_irqs(void)
 
 static void close_one_chan(struct chan *chan, int delay_free_irq)
 {
+        unsigned long flags;
+
         if(!chan->opened)
                 return;
 
         if(delay_free_irq){
-                spin_lock_irq(&irqs_to_free_lock);
+                spin_lock_irqsave(&irqs_to_free_lock, flags);
                 list_add(&chan->free_list, &irqs_to_free);
-                spin_unlock_irq(&irqs_to_free_lock);
+                spin_unlock_irqrestore(&irqs_to_free_lock, flags);
         }
         else {
                 if(chan->input)
diff --git a/arch/um/drivers/daemon_user.c b/arch/um/drivers/daemon_user.c
index 310af0f1e49e..021b82c7a759 100644
--- a/arch/um/drivers/daemon_user.c
+++ b/arch/um/drivers/daemon_user.c
@@ -56,30 +56,31 @@ static int connect_to_switch(struct daemon_data *pri)
 
         pri->control = socket(AF_UNIX, SOCK_STREAM, 0);
         if(pri->control < 0){
+                err = -errno;
                 printk("daemon_open : control socket failed, errno = %d\n", 
-                       errno);          
-                return(-errno);
+                       -err);
+                return err;
         }
 
         if(connect(pri->control, (struct sockaddr *) ctl_addr, 
                    sizeof(*ctl_addr)) < 0){
-                printk("daemon_open : control connect failed, errno = %d\n",
-                       errno);
                 err = -errno;
+                printk("daemon_open : control connect failed, errno = %d\n",
+                       -err);
                 goto out;
         }
 
         fd = socket(AF_UNIX, SOCK_DGRAM, 0);
         if(fd < 0){
-                printk("daemon_open : data socket failed, errno = %d\n", 
-                       errno);
                 err = -errno;
+                printk("daemon_open : data socket failed, errno = %d\n",
+                       -err);
                 goto out;
         }
         if(bind(fd, (struct sockaddr *) local_addr, sizeof(*local_addr)) < 0){
-                printk("daemon_open : data bind failed, errno = %d\n", 
-                       errno);
                 err = -errno;
+                printk("daemon_open : data bind failed, errno = %d\n",
+                       -err);
                 goto out_close;
         }
 
diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index 01d4ab6b0ef1..f75d7b05c481 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -370,10 +370,10 @@ static irqreturn_t line_write_interrupt(int irq, void *data)
         struct tty_struct *tty = line->tty;
         int err;
 
-        /* Interrupts are enabled here because we registered the interrupt with
+        /* Interrupts are disabled here because we registered the interrupt with
          * IRQF_DISABLED (see line_setup_irq).*/
 
-        spin_lock_irq(&line->lock);
+        spin_lock(&line->lock);
         err = flush_buffer(line);
         if (err == 0) {
                 return IRQ_NONE;
@@ -381,7 +381,7 @@ static irqreturn_t line_write_interrupt(int irq, void *data)
                 line->head = line->buffer;
                 line->tail = line->buffer;
         }
-        spin_unlock_irq(&line->lock);
+        spin_unlock(&line->lock);
 
         if(tty == NULL)
                 return IRQ_NONE;
diff --git a/arch/um/drivers/mcast_user.c b/arch/um/drivers/mcast_user.c
index 8138f5ea1bf7..b827e82884c9 100644
--- a/arch/um/drivers/mcast_user.c
+++ b/arch/um/drivers/mcast_user.c
@@ -50,6 +50,14 @@ static void mcast_user_init(void *data, void *dev)
         pri->dev = dev;
 }
 
+static void mcast_remove(void *data)
+{
+        struct mcast_data *pri = data;
+
+        kfree(pri->mcast_addr);
+        pri->mcast_addr = NULL;
+}
+
 static int mcast_open(void *data)
 {
         struct mcast_data *pri = data;
@@ -157,7 +165,7 @@ const struct net_user_info mcast_user_info = {
         .init           = mcast_user_init,
         .open           = mcast_open,
         .close          = mcast_close,
-        .remove         = NULL,
+        .remove         = mcast_remove,
         .set_mtu        = mcast_set_mtu,
         .add_address    = NULL,
         .delete_address = NULL,
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index 178b2eff4a8c..65ad2932672c 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -615,6 +615,9 @@ void mconsole_remove(struct mc_request *req)
         err_msg = NULL;
         err = (*dev->remove)(n, &err_msg);
         switch(err){
+        case 0:
+                err_msg = "";
+                break;
         case -ENODEV:
                 if(err_msg == NULL)
                         err_msg = "Device doesn't exist";
diff --git a/arch/um/drivers/ssl.c b/arch/um/drivers/ssl.c
index fc22b9bd9153..4b382a6e710f 100644
--- a/arch/um/drivers/ssl.c
+++ b/arch/um/drivers/ssl.c
@@ -179,7 +179,7 @@ static struct console ssl_cons = {
         .write          = ssl_console_write,
         .device         = ssl_console_device,
         .setup          = ssl_console_setup,
-        .flags          = CON_PRINTBUFFER,
+        .flags          = CON_PRINTBUFFER|CON_ANYTIME,
         .index          = -1,
 };
 
diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c
index 7ff0b0fc37e7..76d1f1c980ef 100644
--- a/arch/um/drivers/stdio_console.c
+++ b/arch/um/drivers/stdio_console.c
@@ -153,7 +153,7 @@ static struct console stdiocons = {
         .write          = uml_console_write,
         .device         = uml_console_device,
         .setup          = uml_console_setup,
-        .flags          = CON_PRINTBUFFER,
+        .flags          = CON_PRINTBUFFER|CON_ANYTIME,
         .index          = -1,
 };
 
diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index f98d26e51381..8bd9204ac1ab 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -109,10 +109,6 @@ static inline void ubd_set_bit(__u64 bit, unsigned char *data)
 
 static DEFINE_MUTEX(ubd_lock);
 
-/* XXX - this made sense in 2.4 days, now it's only used as a boolean, and
- * probably it doesn't make sense even for that. */
-static int do_ubd;
-
 static int ubd_open(struct inode * inode, struct file * filp);
 static int ubd_release(struct inode * inode, struct file * file);
 static int ubd_ioctl(struct inode * inode, struct file * file,
@@ -169,6 +165,7 @@ struct ubd {
         struct platform_device pdev;
         struct request_queue *queue;
         spinlock_t lock;
+        int active;
 };
 
 #define DEFAULT_COW { \
@@ -190,6 +187,7 @@ struct ubd {
         .shared =               0, \
         .cow =                  DEFAULT_COW, \
         .lock =                 SPIN_LOCK_UNLOCKED,     \
+        .active =               0, \
 }
 
 /* Protected by ubd_lock */
@@ -507,7 +505,6 @@ static void ubd_handler(void)
         struct ubd *dev;
         int n;
 
-        do_ubd = 0;
         n = os_read_file(thread_fd, &req, sizeof(req));
         if(n != sizeof(req)){
                 printk(KERN_ERR "Pid %d - spurious interrupt in ubd_handler, "
@@ -517,6 +514,7 @@ static void ubd_handler(void)
 
         rq = req.req;
         dev = rq->rq_disk->private_data;
+        dev->active = 0;
 
         ubd_finish(rq, req.error);
         reactivate_fd(thread_fd, UBD_IRQ);
@@ -1081,11 +1079,12 @@ static void do_ubd_request(request_queue_t *q)
                 }
         }
         else {
-                if(do_ubd || (req = elv_next_request(q)) == NULL)
+                struct ubd *dev = q->queuedata;
+                if(dev->active || (req = elv_next_request(q)) == NULL)
                         return;
                 err = prepare_request(req, &io_req);
                 if(!err){
-                        do_ubd = 1;
+                        dev->active = 1;
                         n = os_write_file(thread_fd, (char *) &io_req,
                                          sizeof(io_req));
                         if(n != sizeof(io_req))
diff --git a/arch/um/include/mconsole.h b/arch/um/include/mconsole.h
index 2666815b6af5..b282839c1625 100644
--- a/arch/um/include/mconsole.h
+++ b/arch/um/include/mconsole.h
@@ -12,6 +12,8 @@
 #define u32 uint32_t
 #endif
 
+#include "sysdep/ptrace.h"
+
 #define MCONSOLE_MAGIC (0xcafebabe)
 #define MCONSOLE_MAX_DATA (512)
 #define MCONSOLE_VERSION 2
diff --git a/arch/um/include/os.h b/arch/um/include/os.h
index 8629bd191492..5c74da410451 100644
--- a/arch/um/include/os.h
+++ b/arch/um/include/os.h
@@ -192,7 +192,9 @@ extern int os_process_parent(int pid);
 extern void os_stop_process(int pid);
 extern void os_kill_process(int pid, int reap_child);
 extern void os_kill_ptraced_process(int pid, int reap_child);
+#ifdef UML_CONFIG_MODE_TT
 extern void os_usr1_process(int pid);
+#endif
 extern long os_ptrace_ldt(long pid, long addr, long data);
 
 extern int os_getpid(void);
@@ -261,7 +263,6 @@ extern void block_signals(void);
 extern void unblock_signals(void);
 extern int get_signals(void);
 extern int set_signals(int enable);
-extern void os_usr1_signal(int on);
 
 /* trap.c */
 extern void os_fill_handlinfo(struct kern_handlers h);
diff --git a/arch/um/include/sysdep-x86_64/ptrace.h b/arch/um/include/sysdep-x86_64/ptrace.h
index 66cb400c2c92..62403bd99661 100644
--- a/arch/um/include/sysdep-x86_64/ptrace.h
+++ b/arch/um/include/sysdep-x86_64/ptrace.h
@@ -104,10 +104,6 @@ union uml_pt_regs {
 #endif
 #ifdef UML_CONFIG_MODE_SKAS
         struct skas_regs {
-                /* x86_64 ptrace uses sizeof(user_regs_struct) as its register
-                 * file size, while i386 uses FRAME_SIZE.  Therefore, we need
-                 * to use UM_FRAME_SIZE here instead of HOST_FRAME_SIZE.
-                 */
                 unsigned long regs[MAX_REG_NR];
                 unsigned long fp[HOST_FP_SIZE];
                 struct faultinfo faultinfo;
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 50a288bb875a..dbf2f5bc842f 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -142,6 +142,7 @@ int activate_fd(int irq, int fd, int type, void *dev_id)
                                      .events            = events,
                                      .current_events    = 0 } );
 
+        err = -EBUSY;
         spin_lock_irqsave(&irq_lock, flags);
         for (irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next) {
                 if ((irq_fd->fd == fd) && (irq_fd->type == type)) {
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index e85d65deea0d..df7d662b98ce 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -64,8 +64,6 @@ static void setup_highmem(unsigned long highmem_start,
 
 void mem_init(void)
 {
-        max_low_pfn = (high_physmem - uml_physmem) >> PAGE_SHIFT;
-
         /* clear the zero-page */
         memset((void *) empty_zero_page, 0, PAGE_SIZE);
 
@@ -80,6 +78,7 @@ void mem_init(void)
 
         /* this will put all low memory onto the freelists */
         totalram_pages = free_all_bootmem();
+        max_low_pfn = totalram_pages;
 #ifdef CONFIG_HIGHMEM
         totalhigh_pages = highmem >> PAGE_SHIFT;
         totalram_pages += totalhigh_pages;
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
index c692a192957a..76bdd6712417 100644
--- a/arch/um/os-Linux/process.c
+++ b/arch/um/os-Linux/process.c
@@ -21,6 +21,7 @@
 #include "longjmp.h"
 #include "skas_ptrace.h"
 #include "kern_constants.h"
+#include "uml-config.h"
 
 #define ARBITRARY_ADDR -1
 #define FAILURE_PID    -1
@@ -131,10 +132,12 @@ void os_kill_ptraced_process(int pid, int reap_child)
                 CATCH_EINTR(waitpid(pid, NULL, 0));
 }
 
+#ifdef UML_CONFIG_MODE_TT
 void os_usr1_process(int pid)
 {
         kill(pid, SIGUSR1);
 }
+#endif
 
 /* Don't use the glibc version, which caches the result in TLS. It misses some
  * syscalls, and also breaks with clone(), which does not unshare the TLS.
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index b897e8592d77..266768629fee 100644
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -243,8 +243,3 @@ int set_signals(int enable)
 
         return ret;
 }
-
-void os_usr1_signal(int on)
-{
-        change_sig(SIGUSR1, on);
-}
diff --git a/arch/um/os-Linux/skas/mem.c b/arch/um/os-Linux/skas/mem.c
index b3c11cfa995a..9383e8751ae7 100644
--- a/arch/um/os-Linux/skas/mem.c
+++ b/arch/um/os-Linux/skas/mem.c
@@ -48,7 +48,7 @@ int multi_op_count = 0;
 static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr)
 {
         unsigned long regs[MAX_REG_NR];
-        int n;
+        int n, i;
         long ret, offset;
         unsigned long * data;
         unsigned long * syscall;
@@ -66,9 +66,13 @@ static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr)
                  (unsigned long) &__syscall_stub_start);
 
         n = ptrace_setregs(pid, regs);
-        if(n < 0)
+        if(n < 0){
+                printk("Registers - \n");
+                for(i = 0; i < MAX_REG_NR; i++)
+                        printk("\t%d\t0x%lx\n", i, regs[i]);
                 panic("do_syscall_stub : PTRACE_SETREGS failed, errno = %d\n",
-                      n);
+                      -n);
+        }
 
         wait_stub_done(pid, 0, "do_syscall_stub");
 
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index dda06789bcb0..0564422c155f 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -67,7 +67,7 @@ void wait_stub_done(int pid, int sig, char * fname)
 
         if((n < 0) || !WIFSTOPPED(status) ||
            (WSTOPSIG(status) != SIGUSR1 && WSTOPSIG(status) != SIGTRAP)){
-                unsigned long regs[HOST_FRAME_SIZE];
+                unsigned long regs[MAX_REG_NR];
 
                 if(ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
                         printk("Failed to get registers from stub, "
@@ -76,7 +76,7 @@ void wait_stub_done(int pid, int sig, char * fname)
                         int i;
 
                         printk("Stub registers -\n");
-                        for(i = 0; i < HOST_FRAME_SIZE; i++)
+                        for(i = 0; i < ARRAY_SIZE(regs); i++)
                                 printk("\t%d - %lx\n", i, regs[i]);
                 }
                 panic("%s : failed to wait for SIGUSR1/SIGTRAP, "
@@ -328,7 +328,7 @@ void userspace(union uml_pt_regs *regs)
 int copy_context_skas0(unsigned long new_stack, int pid)
 {
         int err;
-        unsigned long regs[HOST_FRAME_SIZE];
+        unsigned long regs[MAX_REG_NR];
         unsigned long fp_regs[HOST_FP_SIZE];
         unsigned long current_stack = current_stub_stack();
         struct stub_data *data = (struct stub_data *) current_stack;
diff --git a/arch/um/os-Linux/sys-i386/registers.c b/arch/um/os-Linux/sys-i386/registers.c
index 79cd93c8c5ed..84b44f9cd42a 100644
--- a/arch/um/os-Linux/sys-i386/registers.c
+++ b/arch/um/os-Linux/sys-i386/registers.c
@@ -15,7 +15,7 @@
 
 /* These are set once at boot time and not changed thereafter */
 
-static unsigned long exec_regs[HOST_FRAME_SIZE];
+static unsigned long exec_regs[MAX_REG_NR];
 static unsigned long exec_fp_regs[HOST_FP_SIZE];
 static unsigned long exec_fpx_regs[HOST_XFP_SIZE];
 static int have_fpx_regs = 1;
@@ -101,6 +101,7 @@ void init_registers(int pid)
 {
         int err;
 
+        memset(exec_regs, 0, sizeof(exec_regs));
         err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
         if(err)
                 panic("check_ptrace : PTRACE_GETREGS failed, errno = %d",
@@ -124,7 +125,7 @@ void init_registers(int pid)
 
 void get_safe_registers(unsigned long *regs, unsigned long *fp_regs)
 {
-        memcpy(regs, exec_regs, HOST_FRAME_SIZE * sizeof(unsigned long));
+        memcpy(regs, exec_regs, sizeof(exec_regs));
         if(fp_regs != NULL)
                 memcpy(fp_regs, exec_fp_regs,
                        HOST_FP_SIZE * sizeof(unsigned long));
diff --git a/arch/um/os-Linux/sys-x86_64/registers.c b/arch/um/os-Linux/sys-x86_64/registers.c
index a2d7e0c603f7..e6fc2179d1bc 100644
--- a/arch/um/os-Linux/sys-x86_64/registers.c
+++ b/arch/um/os-Linux/sys-x86_64/registers.c
@@ -14,7 +14,7 @@
 
 /* These are set once at boot time and not changed thereafter */
 
-static unsigned long exec_regs[HOST_FRAME_SIZE];
+static unsigned long exec_regs[MAX_REG_NR];
 static unsigned long exec_fp_regs[HOST_FP_SIZE];
 
 void init_thread_registers(union uml_pt_regs *to)
@@ -72,7 +72,7 @@ void init_registers(int pid)
 
 void get_safe_registers(unsigned long *regs, unsigned long *fp_regs)
 {
-        memcpy(regs, exec_regs, HOST_FRAME_SIZE * sizeof(unsigned long));
+        memcpy(regs, exec_regs, sizeof(exec_regs));
         if(fp_regs != NULL)
                 memcpy(fp_regs, exec_fp_regs,
                        HOST_FP_SIZE * sizeof(unsigned long));
diff --git a/arch/um/scripts/Makefile.rules b/arch/um/scripts/Makefile.rules
index 813077fb1e5b..a9a4b85ca516 100644
--- a/arch/um/scripts/Makefile.rules
+++ b/arch/um/scripts/Makefile.rules
@@ -10,7 +10,7 @@ USER_OBJS := $(foreach file,$(USER_OBJS),$(obj)/$(file))
 $(USER_OBJS:.o=.%): \
         c_flags = -Wp,-MD,$(depfile) $(USER_CFLAGS) $(CFLAGS_$(basetarget).o)
 $(USER_OBJS) : CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ \
-        -Dunix -D__unix__ -D__$(SUBARCH)__
+        -Dunix -D__unix__ -D__$(SUBARCH)__ $(CF)
 
 # These are like USER_OBJS but filter USER_CFLAGS through unprofile instead of
 # using it directly.
@@ -19,7 +19,7 @@ UNPROFILE_OBJS := $(foreach file,$(UNPROFILE_OBJS),$(obj)/$(file))
 $(UNPROFILE_OBJS:.o=.%): \
         c_flags = -Wp,-MD,$(depfile) $(call unprofile,$(USER_CFLAGS)) $(CFLAGS_$(basetarget).o)
 $(UNPROFILE_OBJS) : CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ \
-        -Dunix -D__unix__ -D__$(SUBARCH)__
+        -Dunix -D__unix__ -D__$(SUBARCH)__ $(CF)
 
 # The stubs and unmap.o can't try to call mcount or update basic block data
 define unprofile
diff --git a/arch/um/sys-i386/delay.c b/arch/um/sys-i386/delay.c
index 2c11b9770e8b..d623e074f41d 100644
--- a/arch/um/sys-i386/delay.c
+++ b/arch/um/sys-i386/delay.c
@@ -27,14 +27,3 @@ void __udelay(unsigned long usecs)
 }
 
 EXPORT_SYMBOL(__udelay);
-
-void __const_udelay(unsigned long usecs)
-{
-        int i, n;
-
-        n = (loops_per_jiffy * HZ * usecs) / MILLION;
-        for(i=0;i<n;i++)
-                cpu_relax();
-}
-
-EXPORT_SYMBOL(__const_udelay);
diff --git a/arch/um/sys-i386/ldt.c b/arch/um/sys-i386/ldt.c
index 4a8b4202ef9e..a939a7ef0227 100644
--- a/arch/um/sys-i386/ldt.c
+++ b/arch/um/sys-i386/ldt.c
@@ -394,7 +394,8 @@ static short * host_ldt_entries = NULL;
 static void ldt_get_host_info(void)
 {
         long ret;
-        struct ldt_entry * ldt, *tmp;
+        struct ldt_entry * ldt;
+        short *tmp;
         int i, size, k, order;
 
         spin_lock(&host_ldt_lock);
diff --git a/arch/um/sys-x86_64/delay.c b/arch/um/sys-x86_64/delay.c
index 137f4446b439..dee5be66da82 100644
--- a/arch/um/sys-x86_64/delay.c
+++ b/arch/um/sys-x86_64/delay.c
@@ -28,14 +28,3 @@ void __udelay(unsigned long usecs)
 }
 
 EXPORT_SYMBOL(__udelay);
-
-void __const_udelay(unsigned long usecs)
-{
-        unsigned long i, n;
-
-        n = (loops_per_jiffy * HZ * usecs) / MILLION;
-        for(i=0;i<n;i++)
-                cpu_relax();
-}
-
-EXPORT_SYMBOL(__const_udelay);
diff --git a/arch/um/sys-x86_64/syscalls.c b/arch/um/sys-x86_64/syscalls.c
index 01b91f9fa789..b3f6350cac44 100644
--- a/arch/um/sys-x86_64/syscalls.c
+++ b/arch/um/sys-x86_64/syscalls.c
@@ -103,6 +103,9 @@ long arch_prctl_skas(struct task_struct *task, int code,
 
         switch(code){
         case ARCH_SET_FS:
+                current->thread.arch.fs = (unsigned long) ptr;
+                save_registers(pid, &current->thread.regs.regs);
+                break;
         case ARCH_SET_GS:
                 save_registers(pid, &current->thread.regs.regs);
                 break;
@@ -140,9 +143,8 @@ long sys_clone(unsigned long clone_flags, unsigned long newsp,
 
 void arch_switch_to_skas(struct task_struct *from, struct task_struct *to)
 {
-        if(to->thread.arch.fs == 0)
+        if((to->thread.arch.fs == 0) || (to->mm == NULL))
                 return;
 
         arch_prctl_skas(to, ARCH_SET_FS, (void __user *) to->thread.arch.fs);
 }
-