Merge linux-2.6 with linux-acpi-2.6

11 files changed, 355 insertions, 207 deletions

diff --git a/arch/um/kernel/skas/Makefile b/arch/um/kernel/skas/Makefile
index d296d55..db36c7c 100644
--- a/arch/um/kernel/skas/Makefile
+++ b/arch/um/kernel/skas/Makefile
@@ -4,7 +4,7 @@
 #
 
 obj-y := clone.o exec_kern.o mem.o mem_user.o mmu.o process.o process_kern.o \
-	syscall_kern.o syscall_user.o tlb.o trap_user.o uaccess.o \
+	syscall.o tlb.o trap_user.o uaccess.o
 
 subdir- := util
 
diff --git a/arch/um/kernel/skas/include/mmu-skas.h b/arch/um/kernel/skas/include/mmu-skas.h
index 278b72f..09536f8 100644
--- a/arch/um/kernel/skas/include/mmu-skas.h
+++ b/arch/um/kernel/skas/include/mmu-skas.h
@@ -6,11 +6,15 @@
 #ifndef __SKAS_MMU_H
 #define __SKAS_MMU_H
 
+#include "linux/config.h"
 #include "mm_id.h"
 
 struct mmu_context_skas {
 	struct mm_id id;
         unsigned long last_page_table;
+#ifdef CONFIG_3_LEVEL_PGTABLES
+        unsigned long last_pmd;
+#endif
 };
 
 extern void switch_mm_skas(struct mm_id * mm_idp);
diff --git a/arch/um/kernel/skas/include/skas.h b/arch/um/kernel/skas/include/skas.h
index d983ea8..0609347 100644
--- a/arch/um/kernel/skas/include/skas.h
+++ b/arch/um/kernel/skas/include/skas.h
@@ -24,28 +24,26 @@ extern void new_thread_proc(void *stack, void (*handler)(int sig));
 extern void remove_sigstack(void);
 extern void new_thread_handler(int sig);
 extern void handle_syscall(union uml_pt_regs *regs);
-extern int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len,
-               int r, int w, int x, int phys_fd, unsigned long long offset);
-extern int unmap(struct mm_id * mm_idp, void *addr, unsigned long len);
+extern int map(struct mm_id * mm_idp, unsigned long virt,
+	       unsigned long len, int r, int w, int x, int phys_fd,
+	       unsigned long long offset, int done, void **data);
+extern int unmap(struct mm_id * mm_idp, void *addr, unsigned long len,
+		 int done, void **data);
 extern int protect(struct mm_id * mm_idp, unsigned long addr,
-		   unsigned long len, int r, int w, int x);
+		   unsigned long len, int r, int w, int x, int done,
+		   void **data);
 extern void user_signal(int sig, union uml_pt_regs *regs, int pid);
-extern int new_mm(int from);
+extern int new_mm(int from, unsigned long stack);
 extern int start_userspace(unsigned long stub_stack);
 extern int copy_context_skas0(unsigned long stack, int pid);
 extern void get_skas_faultinfo(int pid, struct faultinfo * fi);
 extern long execute_syscall_skas(void *r);
 extern unsigned long current_stub_stack(void);
+extern long run_syscall_stub(struct mm_id * mm_idp,
+                             int syscall, unsigned long *args, long expected,
+                             void **addr, int done);
+extern long syscall_stub_data(struct mm_id * mm_idp,
+                              unsigned long *data, int data_count,
+                              void **addr, void **stub_addr);
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/kernel/skas/mem_user.c b/arch/um/kernel/skas/mem_user.c
index b0980ff..1d89640 100644
--- a/arch/um/kernel/skas/mem_user.c
+++ b/arch/um/kernel/skas/mem_user.c
@@ -5,13 +5,14 @@
 
 #include <signal.h>
 #include <errno.h>
+#include <string.h>
 #include <sys/mman.h>
 #include <sys/wait.h>
 #include <asm/page.h>
 #include <asm/unistd.h>
 #include "mem_user.h"
 #include "mem.h"
-#include "mm_id.h"
+#include "skas.h"
 #include "user.h"
 #include "os.h"
 #include "proc_mm.h"
@@ -23,46 +24,155 @@
 #include "uml-config.h"
 #include "sysdep/ptrace.h"
 #include "sysdep/stub.h"
-#include "skas.h"
 
-extern unsigned long syscall_stub, __syscall_stub_start;
+extern unsigned long batch_syscall_stub, __syscall_stub_start;
 
 extern void wait_stub_done(int pid, int sig, char * fname);
 
-static long run_syscall_stub(struct mm_id * mm_idp, int syscall,
-                             unsigned long *args)
+static inline unsigned long *check_init_stack(struct mm_id * mm_idp,
+					      unsigned long *stack)
+{
+	if(stack == NULL){
+		stack = (unsigned long *) mm_idp->stack + 2;
+		*stack = 0;
+	}
+	return stack;
+}
+
+extern int proc_mm;
+
+int single_count = 0;
+int multi_count = 0;
+int multi_op_count = 0;
+
+static long do_syscall_stub(struct mm_id *mm_idp, void **addr)
 {
+	unsigned long regs[MAX_REG_NR];
+	unsigned long *data;
+	unsigned long *syscall;
+	long ret, offset;
         int n, pid = mm_idp->u.pid;
-        unsigned long regs[MAX_REG_NR];
+
+	if(proc_mm)
+#warning Need to look up userspace_pid by cpu
+		pid = userspace_pid[0];
+
+	multi_count++;
 
         get_safe_registers(regs);
         regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE +
-                ((unsigned long) &syscall_stub -
+		((unsigned long) &batch_syscall_stub -
                  (unsigned long) &__syscall_stub_start);
-        /* XXX Don't have a define for starting a syscall */
-        regs[REGS_SYSCALL_NR] = syscall;
-        regs[REGS_SYSCALL_ARG1] = args[0];
-        regs[REGS_SYSCALL_ARG2] = args[1];
-        regs[REGS_SYSCALL_ARG3] = args[2];
-        regs[REGS_SYSCALL_ARG4] = args[3];
-        regs[REGS_SYSCALL_ARG5] = args[4];
-        regs[REGS_SYSCALL_ARG6] = args[5];
-        n = ptrace_setregs(pid, regs);
-        if(n < 0){
-                printk("run_syscall_stub : PTRACE_SETREGS failed, "
-                       "errno = %d\n", n);
-                return(n);
+	n = ptrace_setregs(pid, regs);
+	if(n < 0)
+		panic("do_syscall_stub : PTRACE_SETREGS failed, errno = %d\n",
+		      n);
+
+	wait_stub_done(pid, 0, "do_syscall_stub");
+
+	/* When the stub stops, we find the following values on the
+	 * beginning of the stack:
+	 * (long )return_value
+	 * (long )offset to failed sycall-data (0, if no error)
+	 */
+	ret = *((unsigned long *) mm_idp->stack);
+	offset = *((unsigned long *) mm_idp->stack + 1);
+	if (offset) {
+		data = (unsigned long *)(mm_idp->stack +
+					 offset - UML_CONFIG_STUB_DATA);
+		syscall = (unsigned long *)((unsigned long)data + data[0]);
+		printk("do_syscall_stub: syscall %ld failed, return value = "
+		       "0x%lx, expected return value = 0x%lx\n",
+		       syscall[0], ret, syscall[7]);
+		printk("    syscall parameters: "
+		       "0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
+		       syscall[1], syscall[2], syscall[3],
+		       syscall[4], syscall[5], syscall[6]);
+		for(n = 1; n < data[0]/sizeof(long); n++) {
+			if(n == 1)
+				printk("    additional syscall data:");
+			if(n % 4 == 1)
+				printk("\n      ");
+			printk("  0x%lx", data[n]);
+		}
+		if(n > 1)
+			printk("\n");
+	}
+	else ret = 0;
+
+	*addr = check_init_stack(mm_idp, NULL);
+
+	return ret;
+}
+
+long run_syscall_stub(struct mm_id * mm_idp, int syscall,
+		      unsigned long *args, long expected, void **addr,
+ 		      int done)
+{
+ 	unsigned long *stack = check_init_stack(mm_idp, *addr);
+
+	if(done && *addr == NULL)
+		single_count++;
+
+ 	*stack += sizeof(long);
+	stack += *stack / sizeof(long);
+
+        *stack++ = syscall;
+        *stack++ = args[0];
+        *stack++ = args[1];
+        *stack++ = args[2];
+        *stack++ = args[3];
+        *stack++ = args[4];
+        *stack++ = args[5];
+	*stack++ = expected;
+        *stack = 0;
+        multi_op_count++;
+
+        if(!done && ((((unsigned long) stack) & ~PAGE_MASK) <
+		     PAGE_SIZE - 10 * sizeof(long))){
+		*addr = stack;
+                return 0;
         }
 
-        wait_stub_done(pid, 0, "run_syscall_stub");
+	return do_syscall_stub(mm_idp, addr);
+}
+
+long syscall_stub_data(struct mm_id * mm_idp,
+		       unsigned long *data, int data_count,
+		       void **addr, void **stub_addr)
+{
+	unsigned long *stack;
+	int ret = 0;
 
-        return(*((unsigned long *) mm_idp->stack));
+	/* If *addr still is uninitialized, it *must* contain NULL.
+	 * Thus in this case do_syscall_stub correctly won't be called.
+	 */
+	if((((unsigned long) *addr) & ~PAGE_MASK) >=
+	   PAGE_SIZE - (10 + data_count) * sizeof(long)) {
+		ret = do_syscall_stub(mm_idp, addr);
+ 		/* in case of error, don't overwrite data on stack */
+		if(ret)
+			return ret;
+	}
+
+	stack = check_init_stack(mm_idp, *addr);
+	*addr = stack;
+
+	*stack = data_count * sizeof(long);
+
+	memcpy(stack + 1, data, data_count * sizeof(long));
+
+	*stub_addr = (void *)(((unsigned long)(stack + 1) & ~PAGE_MASK) +
+			      UML_CONFIG_STUB_DATA);
+
+	return 0;
 }
 
-int map(struct mm_id *mm_idp, unsigned long virt, unsigned long len,
-        int r, int w, int x, int phys_fd, unsigned long long offset)
+int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len,
+	int r, int w, int x, int phys_fd, unsigned long long offset,
+	int done, void **data)
 {
-        int prot, n;
+        int prot, ret;
 
         prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) |
                 (x ? PROT_EXEC : 0);
@@ -70,6 +180,7 @@ int map(struct mm_id *mm_idp, unsigned long virt, unsigned long len,
         if(proc_mm){
                 struct proc_mm_op map;
                 int fd = mm_idp->u.mm_fd;
+
                 map = ((struct proc_mm_op) { .op	= MM_MMAP,
                                              .u		=
                                              { .mmap	=
@@ -81,63 +192,61 @@ int map(struct mm_id *mm_idp, unsigned long virt, unsigned long len,
                                                  .fd	= phys_fd,
                                                  .offset= offset
                                                } } } );
-                n = os_write_file(fd, &map, sizeof(map));
-                if(n != sizeof(map))
-                        printk("map : /proc/mm map failed, err = %d\n", -n);
+		ret = os_write_file(fd, &map, sizeof(map));
+		if(ret != sizeof(map))
+			printk("map : /proc/mm map failed, err = %d\n", -ret);
+		else ret = 0;
         }
         else {
-                long res;
                 unsigned long args[] = { virt, len, prot,
                                          MAP_SHARED | MAP_FIXED, phys_fd,
                                          MMAP_OFFSET(offset) };
 
-                res = run_syscall_stub(mm_idp, STUB_MMAP_NR, args);
-                if((void *) res == MAP_FAILED)
-                        printk("mmap stub failed, errno = %d\n", res);
+		ret = run_syscall_stub(mm_idp, STUB_MMAP_NR, args, virt,
+				       data, done);
         }
 
-        return 0;
+	return ret;
 }
 
-int unmap(struct mm_id *mm_idp, void *addr, unsigned long len)
+int unmap(struct mm_id * mm_idp, void *addr, unsigned long len, int done,
+	  void **data)
 {
-        int n;
+        int ret;
 
         if(proc_mm){
                 struct proc_mm_op unmap;
                 int fd = mm_idp->u.mm_fd;
+
                 unmap = ((struct proc_mm_op) { .op	= MM_MUNMAP,
                                                .u	=
                                                { .munmap	=
                                                  { .addr	=
                                                    (unsigned long) addr,
                                                    .len		= len } } } );
-                n = os_write_file(fd, &unmap, sizeof(unmap));
-                if(n != sizeof(unmap)) {
-                        if(n < 0)
-                                return(n);
-                        else if(n > 0)
-                                return(-EIO);
-                }
+		ret = os_write_file(fd, &unmap, sizeof(unmap));
+		if(ret != sizeof(unmap))
+			printk("unmap - proc_mm write returned %d\n", ret);
+		else ret = 0;
         }
         else {
-                int res;
                 unsigned long args[] = { (unsigned long) addr, len, 0, 0, 0,
                                          0 };
 
-                res = run_syscall_stub(mm_idp, __NR_munmap, args);
-                if(res < 0)
-                        printk("munmap stub failed, errno = %d\n", res);
+		ret = run_syscall_stub(mm_idp, __NR_munmap, args, 0,
+				       data, done);
+                if(ret < 0)
+                        printk("munmap stub failed, errno = %d\n", ret);
         }
 
-        return(0);
+        return ret;
 }
 
-int protect(struct mm_id *mm_idp, unsigned long addr, unsigned long len,
-	    int r, int w, int x)
+int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len,
+	    int r, int w, int x, int done, void **data)
 {
         struct proc_mm_op protect;
-        int prot, n;
+        int prot, ret;
 
         prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) |
                 (x ? PROT_EXEC : 0);
@@ -152,20 +261,19 @@ int protect(struct mm_id *mm_idp, unsigned long addr, unsigned long len,
                                                      .len	= len,
                                                      .prot	= prot } } } );
 
-                n = os_write_file(fd, &protect, sizeof(protect));
-                if(n != sizeof(protect))
-                        panic("protect failed, err = %d", -n);
+                ret = os_write_file(fd, &protect, sizeof(protect));
+                if(ret != sizeof(protect))
+                        printk("protect failed, err = %d", -ret);
+                else ret = 0;
         }
         else {
-                int res;
                 unsigned long args[] = { addr, len, prot, 0, 0, 0 };
 
-                res = run_syscall_stub(mm_idp, __NR_mprotect, args);
-                if(res < 0)
-                        panic("mprotect stub failed, errno = %d\n", res);
+                ret = run_syscall_stub(mm_idp, __NR_mprotect, args, 0,
+                                       data, done);
         }
 
-        return(0);
+        return ret;
 }
 
 void before_mem_skas(unsigned long unused)
diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c
index d232daa..240143b 100644
--- a/arch/um/kernel/skas/mmu.c
+++ b/arch/um/kernel/skas/mmu.c
@@ -56,6 +56,9 @@ static int init_stub_pte(struct mm_struct *mm, unsigned long proc,
 	 */
 
         mm->context.skas.last_page_table = pmd_page_kernel(*pmd);
+#ifdef CONFIG_3_LEVEL_PGTABLES
+        mm->context.skas.last_pmd = (unsigned long) __va(pud_val(*pud));
+#endif
 
 	*pte = mk_pte(virt_to_page(kernel), __pgprot(_PAGE_PRESENT));
 	*pte = pte_mkexec(*pte);
@@ -77,23 +80,14 @@ int init_new_context_skas(struct task_struct *task, struct mm_struct *mm)
 	struct mm_struct *cur_mm = current->mm;
 	struct mm_id *cur_mm_id = &cur_mm->context.skas.id;
 	struct mm_id *mm_id = &mm->context.skas.id;
-	unsigned long stack;
-	int from, ret;
+	unsigned long stack = 0;
+	int from, ret = -ENOMEM;
 
-	if(proc_mm){
-		if((cur_mm != NULL) && (cur_mm != &init_mm))
-			from = cur_mm->context.skas.id.u.mm_fd;
-		else from = -1;
+	if(!proc_mm || !ptrace_faultinfo){
+		stack = get_zeroed_page(GFP_KERNEL);
+		if(stack == 0)
+			goto out;
 
-		ret = new_mm(from);
-		if(ret < 0){
-			printk("init_new_context_skas - new_mm failed, "
-			       "errno = %d\n", ret);
-			return ret;
-		}
-		mm_id->u.mm_fd = ret;
-	}
-	else {
 		/* This zeros the entry that pgd_alloc didn't, needed since
 		 * we are about to reinitialize it, and want mm.nr_ptes to
 		 * be accurate.
@@ -103,20 +97,30 @@ int init_new_context_skas(struct task_struct *task, struct mm_struct *mm)
 		ret = init_stub_pte(mm, CONFIG_STUB_CODE,
 				    (unsigned long) &__syscall_stub_start);
 		if(ret)
-			goto out;
-
-		ret = -ENOMEM;
-		stack = get_zeroed_page(GFP_KERNEL);
-		if(stack == 0)
-			goto out;
-		mm_id->stack = stack;
+			goto out_free;
 
 		ret = init_stub_pte(mm, CONFIG_STUB_DATA, stack);
 		if(ret)
 			goto out_free;
 
 		mm->nr_ptes--;
+	}
+	mm_id->stack = stack;
 
+	if(proc_mm){
+		if((cur_mm != NULL) && (cur_mm != &init_mm))
+			from = cur_mm_id->u.mm_fd;
+		else from = -1;
+
+		ret = new_mm(from, stack);
+		if(ret < 0){
+			printk("init_new_context_skas - new_mm failed, "
+			       "errno = %d\n", ret);
+			goto out_free;
+		}
+		mm_id->u.mm_fd = ret;
+	}
+	else {
 		if((cur_mm != NULL) && (cur_mm != &init_mm))
 			mm_id->u.pid = copy_context_skas0(stack,
 							  cur_mm_id->u.pid);
@@ -126,7 +130,8 @@ int init_new_context_skas(struct task_struct *task, struct mm_struct *mm)
 	return 0;
 
  out_free:
-	free_page(mm_id->stack);
+	if(mm_id->stack != 0)
+		free_page(mm_id->stack);
  out:
 	return ret;
 }
@@ -137,9 +142,15 @@ void destroy_context_skas(struct mm_struct *mm)
 
 	if(proc_mm)
 		os_close_file(mmu->id.u.mm_fd);
-	else {
+	else
 		os_kill_ptraced_process(mmu->id.u.pid, 1);
+
+	if(!proc_mm || !ptrace_faultinfo){
 		free_page(mmu->id.stack);
-		free_page(mmu->last_page_table);
+		pte_free_kernel((pte_t *) mmu->last_page_table);
+                dec_page_state(nr_page_table_pages);
+#ifdef CONFIG_3_LEVEL_PGTABLES
+		pmd_free((pmd_t *) mmu->last_pmd);
+#endif
 	}
 }
diff --git a/arch/um/kernel/skas/process.c b/arch/um/kernel/skas/process.c
index f228f8b..5cd0e99 100644
--- a/arch/um/kernel/skas/process.c
+++ b/arch/um/kernel/skas/process.c
@@ -138,6 +138,8 @@ static void handle_trap(int pid, union uml_pt_regs *regs, int local_using_sysemu
 }
 
 extern int __syscall_stub_start;
+int stub_code_fd = -1;
+__u64 stub_code_offset;
 
 static int userspace_tramp(void *stack)
 {
@@ -152,31 +154,31 @@ static int userspace_tramp(void *stack)
 		/* This has a pte, but it can't be mapped in with the usual
 		 * tlb_flush mechanism because this is part of that mechanism
 		 */
-		int fd;
-		__u64 offset;
-
-		fd = phys_mapping(to_phys(&__syscall_stub_start), &offset);
 		addr = mmap64((void *) UML_CONFIG_STUB_CODE, page_size(),
-			      PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset);
+			      PROT_EXEC, MAP_FIXED | MAP_PRIVATE,
+			      stub_code_fd, stub_code_offset);
 		if(addr == MAP_FAILED){
-			printk("mapping mmap stub failed, errno = %d\n",
+			printk("mapping stub code failed, errno = %d\n",
 			       errno);
 			exit(1);
 		}
 
 		if(stack != NULL){
+			int fd;
+			__u64 offset;
+
 			fd = phys_mapping(to_phys(stack), &offset);
 			addr = mmap((void *) UML_CONFIG_STUB_DATA, page_size(),
 				    PROT_READ | PROT_WRITE,
 				    MAP_FIXED | MAP_SHARED, fd, offset);
 			if(addr == MAP_FAILED){
-				printk("mapping segfault stack failed, "
+				printk("mapping stub stack failed, "
 				       "errno = %d\n", errno);
 				exit(1);
 			}
 		}
 	}
-	if(!ptrace_faultinfo && (stack != NULL)){
+	if(!ptrace_faultinfo){
 		unsigned long v = UML_CONFIG_STUB_CODE +
 				  (unsigned long) stub_segv_handler -
 				  (unsigned long) &__syscall_stub_start;
@@ -202,6 +204,10 @@ int start_userspace(unsigned long stub_stack)
 	unsigned long sp;
 	int pid, status, n, flags;
 
+	if ( stub_code_fd == -1 )
+		stub_code_fd = phys_mapping(to_phys(&__syscall_stub_start),
+					    &stub_code_offset);
+
 	stack = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
 		     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 	if(stack == MAP_FAILED)
@@ -363,6 +369,53 @@ int copy_context_skas0(unsigned long new_stack, int pid)
 	return pid;
 }
 
+/*
+ * This is used only, if proc_mm is available, while PTRACE_FAULTINFO
+ * isn't. Opening /proc/mm creates a new mm_context, which lacks the stub-pages
+ * Thus, we map them using /proc/mm-fd
+ */
+void map_stub_pages(int fd, unsigned long code,
+		    unsigned long data, unsigned long stack)
+{
+	struct proc_mm_op mmop;
+	int n;
+
+	mmop = ((struct proc_mm_op) { .op        = MM_MMAP,
+				      .u         =
+				      { .mmap    =
+					{ .addr    = code,
+					  .len     = PAGE_SIZE,
+					  .prot    = PROT_EXEC,
+					  .flags   = MAP_FIXED | MAP_PRIVATE,
+					  .fd      = stub_code_fd,
+					  .offset  = stub_code_offset
+	} } });
+	n = os_write_file(fd, &mmop, sizeof(mmop));
+	if(n != sizeof(mmop))
+		panic("map_stub_pages : /proc/mm map for code failed, "
+		      "err = %d\n", -n);
+
+	if ( stack ) {
+		__u64 map_offset;
+		int map_fd = phys_mapping(to_phys((void *)stack), &map_offset);
+		mmop = ((struct proc_mm_op)
+				{ .op        = MM_MMAP,
+				  .u         =
+				  { .mmap    =
+				    { .addr    = data,
+				      .len     = PAGE_SIZE,
+				      .prot    = PROT_READ | PROT_WRITE,
+				      .flags   = MAP_FIXED | MAP_SHARED,
+				      .fd      = map_fd,
+				      .offset  = map_offset
+		} } });
+		n = os_write_file(fd, &mmop, sizeof(mmop));
+		if(n != sizeof(mmop))
+			panic("map_stub_pages : /proc/mm map for data failed, "
+			      "err = %d\n", -n);
+	}
+}
+
 void new_thread(void *stack, void **switch_buf_ptr, void **fork_buf_ptr,
 		void (*handler)(int))
 {
diff --git a/arch/um/kernel/skas/process_kern.c b/arch/um/kernel/skas/process_kern.c
index cbabab1..3d1b227 100644
--- a/arch/um/kernel/skas/process_kern.c
+++ b/arch/um/kernel/skas/process_kern.c
@@ -129,7 +129,9 @@ int copy_thread_skas(int nr, unsigned long clone_flags, unsigned long sp,
 	return(0);
 }
 
-int new_mm(int from)
+extern void map_stub_pages(int fd, unsigned long code,
+			   unsigned long data, unsigned long stack);
+int new_mm(int from, unsigned long stack)
 {
 	struct proc_mm_op copy;
 	int n, fd;
@@ -148,6 +150,9 @@ int new_mm(int from)
 			       "err = %d\n", -n);
 	}
 
+	if(!ptrace_faultinfo)
+		map_stub_pages(fd, CONFIG_STUB_CODE, CONFIG_STUB_DATA, stack);
+
 	return(fd);
 }
 
diff --git a/arch/um/kernel/skas/syscall.c b/arch/um/kernel/skas/syscall.c
new file mode 100644
index 0000000..51fb940
--- /dev/null
+++ b/arch/um/kernel/skas/syscall.c
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/sys.h"
+#include "linux/ptrace.h"
+#include "asm/errno.h"
+#include "asm/unistd.h"
+#include "asm/ptrace.h"
+#include "asm/current.h"
+#include "sysdep/syscalls.h"
+#include "kern_util.h"
+#include "syscall.h"
+
+void handle_syscall(union uml_pt_regs *r)
+{
+	struct pt_regs *regs = container_of(r, struct pt_regs, regs);
+	long result;
+	int syscall;
+#ifdef UML_CONFIG_SYSCALL_DEBUG
+  	int index;
+
+  	index = record_syscall_start(UPT_SYSCALL_NR(r));
+#endif
+	syscall_trace(r, 0);
+
+	current->thread.nsyscalls++;
+	nsyscalls++;
+
+	/* This should go in the declaration of syscall, but when I do that,
+	 * strace -f -c bash -c 'ls ; ls' breaks, sometimes not tracing
+	 * children at all, sometimes hanging when bash doesn't see the first
+	 * ls exit.
+	 * The assembly looks functionally the same to me.  This is
+	 *     gcc version 4.0.1 20050727 (Red Hat 4.0.1-5)
+	 * in case it's a compiler bug.
+	 */
+	syscall = UPT_SYSCALL_NR(r);
+	if((syscall >= NR_syscalls) || (syscall < 0))
+		result = -ENOSYS;
+	else result = EXECUTE_SYSCALL(syscall, regs);
+
+	REGS_SET_SYSCALL_RETURN(r->skas.regs, result);
+
+	syscall_trace(r, 1);
+#ifdef UML_CONFIG_SYSCALL_DEBUG
+  	record_syscall_end(index, result);
+#endif
+}
diff --git a/arch/um/kernel/skas/syscall_kern.c b/arch/um/kernel/skas/syscall_kern.c
deleted file mode 100644
index bdf040c..0000000
--- a/arch/um/kernel/skas/syscall_kern.c
+++ /dev/null
@@ -1,43 +0,0 @@
-/* 
- * Copyright (C) 2002 - 2003 Jeff Dike (jdike@addtoit.com)
- * Licensed under the GPL
- */
-
-#include "linux/sys.h"
-#include "linux/ptrace.h"
-#include "asm/errno.h"
-#include "asm/unistd.h"
-#include "asm/ptrace.h"
-#include "asm/current.h"
-#include "sysdep/syscalls.h"
-#include "kern_util.h"
-
-extern syscall_handler_t *sys_call_table[];
-
-long execute_syscall_skas(void *r)
-{
-	struct pt_regs *regs = r;
-	long res;
-	int syscall;
-
-	current->thread.nsyscalls++;
-	nsyscalls++;
-	syscall = UPT_SYSCALL_NR(&regs->regs);
-
-	if((syscall >= NR_syscalls) || (syscall < 0))
-		res = -ENOSYS;
-	else res = EXECUTE_SYSCALL(syscall, regs);
-
-	return(res);
-}
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/kernel/skas/syscall_user.c b/arch/um/kernel/skas/syscall_user.c
deleted file mode 100644
index 6b06649..0000000
--- a/arch/um/kernel/skas/syscall_user.c
+++ /dev/null
@@ -1,44 +0,0 @@
-/* 
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
-
-#include <stdlib.h>
-#include <signal.h>
-#include "kern_util.h"
-#include "uml-config.h"
-#include "syscall_user.h"
-#include "sysdep/ptrace.h"
-#include "sysdep/sigcontext.h"
-#include "skas.h"
-
-void handle_syscall(union uml_pt_regs *regs)
-{
-	long result;
-#ifdef UML_CONFIG_SYSCALL_DEBUG
-  	int index;
-
-  	index = record_syscall_start(UPT_SYSCALL_NR(regs));
-#endif
-
-	syscall_trace(regs, 0);
-	result = execute_syscall_skas(regs);
-
-	REGS_SET_SYSCALL_RETURN(regs->skas.regs, result);
-
-	syscall_trace(regs, 1);
-#ifdef UML_CONFIG_SYSCALL_DEBUG
-  	record_syscall_end(index, result);
-#endif
-}
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/kernel/skas/tlb.c b/arch/um/kernel/skas/tlb.c
index 6230999..6e84963 100644
--- a/arch/um/kernel/skas/tlb.c
+++ b/arch/um/kernel/skas/tlb.c
@@ -18,33 +18,39 @@
 #include "os.h"
 #include "tlb.h"
 
-static void do_ops(union mm_context *mmu, struct host_vm_op *ops, int last)
+static int do_ops(union mm_context *mmu, struct host_vm_op *ops, int last,
+		  int finished, void **flush)
 {
 	struct host_vm_op *op;
-	int i;
+        int i, ret = 0;
 
-	for(i = 0; i <= last; i++){
+        for(i = 0; i <= last && !ret; i++){
 		op = &ops[i];
 		switch(op->type){
 		case MMAP:
-                        map(&mmu->skas.id, op->u.mmap.addr, op->u.mmap.len,
-			    op->u.mmap.r, op->u.mmap.w, op->u.mmap.x,
-			    op->u.mmap.fd, op->u.mmap.offset);
+			ret = map(&mmu->skas.id, op->u.mmap.addr,
+				  op->u.mmap.len, op->u.mmap.r, op->u.mmap.w,
+				  op->u.mmap.x, op->u.mmap.fd,
+				  op->u.mmap.offset, finished, flush);
 			break;
 		case MUNMAP:
-                        unmap(&mmu->skas.id, (void *) op->u.munmap.addr,
-			      op->u.munmap.len);
+			ret = unmap(&mmu->skas.id,
+				    (void *) op->u.munmap.addr,
+				    op->u.munmap.len, finished, flush);
 			break;
 		case MPROTECT:
-                        protect(&mmu->skas.id, op->u.mprotect.addr,
-                                op->u.mprotect.len, op->u.mprotect.r,
-                                op->u.mprotect.w, op->u.mprotect.x);
+			ret = protect(&mmu->skas.id, op->u.mprotect.addr,
+				      op->u.mprotect.len, op->u.mprotect.r,
+				      op->u.mprotect.w, op->u.mprotect.x,
+				      finished, flush);
 			break;
 		default:
 			printk("Unknown op type %d in do_ops\n", op->type);
 			break;
 		}
 	}
+
+	return ret;
 }
 
 extern int proc_mm;