6 files changed, 106 insertions, 86 deletions

diff --git a/arch/um/kernel/Makefile b/arch/um/kernel/Makefile
index d8b78a03855c..2d840a070c8b 100644
--- a/arch/um/kernel/Makefile
+++ b/arch/um/kernel/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_BLK_DEV_INITRD) += initrd.o
 obj-$(CONFIG_GPROF)	+= gprof_syms.o
 obj-$(CONFIG_GCOV)	+= gmon_syms.o
 obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
+obj-$(CONFIG_STACKTRACE) += stacktrace.o
 
 USER_OBJS := config.o
 
diff --git a/arch/um/kernel/physmem.c b/arch/um/kernel/physmem.c
index 30fdd5d0067b..549ecf3f5857 100644
--- a/arch/um/kernel/physmem.c
+++ b/arch/um/kernel/physmem.c
@@ -22,39 +22,19 @@ EXPORT_SYMBOL(high_physmem);
 
 extern unsigned long long physmem_size;
 
-int __init init_maps(unsigned long physmem, unsigned long iomem,
+void __init mem_total_pages(unsigned long physmem, unsigned long iomem,
 		     unsigned long highmem)
 {
-	struct page *p, *map;
-	unsigned long phys_len, phys_pages, highmem_len, highmem_pages;
-	unsigned long iomem_len, iomem_pages, total_len, total_pages;
-	int i;
-
-	phys_pages = physmem >> PAGE_SHIFT;
-	phys_len = phys_pages * sizeof(struct page);
-
-	iomem_pages = iomem >> PAGE_SHIFT;
-	iomem_len = iomem_pages * sizeof(struct page);
+	unsigned long phys_pages, highmem_pages;
+	unsigned long iomem_pages, total_pages;
 
+	phys_pages    = physmem >> PAGE_SHIFT;
+	iomem_pages   = iomem   >> PAGE_SHIFT;
 	highmem_pages = highmem >> PAGE_SHIFT;
-	highmem_len = highmem_pages * sizeof(struct page);
-
-	total_pages = phys_pages + iomem_pages + highmem_pages;
-	total_len = phys_len + iomem_len + highmem_len;
 
-	map = alloc_bootmem_low_pages(total_len);
-	if (map == NULL)
-		return -ENOMEM;
-
-	for (i = 0; i < total_pages; i++) {
-		p = &map[i];
-		memset(p, 0, sizeof(struct page));
-		SetPageReserved(p);
-		INIT_LIST_HEAD(&p->lru);
-	}
+	total_pages   = phys_pages + iomem_pages + highmem_pages;
 
 	max_mapnr = total_pages;
-	return 0;
 }
 
 void map_memory(unsigned long virt, unsigned long phys, unsigned long len,
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
index 694d551c8899..62435ef003d9 100644
--- a/arch/um/kernel/ptrace.c
+++ b/arch/um/kernel/ptrace.c
@@ -165,8 +165,7 @@ static void send_sigtrap(struct task_struct *tsk, struct uml_pt_regs *regs,
  */
 void syscall_trace_enter(struct pt_regs *regs)
 {
-	audit_syscall_entry(HOST_AUDIT_ARCH,
-			    UPT_SYSCALL_NR(&regs->regs),
+	audit_syscall_entry(UPT_SYSCALL_NR(&regs->regs),
 			    UPT_SYSCALL_ARG1(&regs->regs),
 			    UPT_SYSCALL_ARG2(&regs->regs),
 			    UPT_SYSCALL_ARG3(&regs->regs),
diff --git a/arch/um/kernel/stacktrace.c b/arch/um/kernel/stacktrace.c
new file mode 100644
index 000000000000..ebe7bcf62684
--- /dev/null
+++ b/arch/um/kernel/stacktrace.c
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Copyright (C) 2013 Richard Weinberger <richard@nod.at>
+ * Copyright (C) 2014 Google Inc., Author: Daniel Walter <dwalter@google.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kallsyms.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <asm/stacktrace.h>
+
+void dump_trace(struct task_struct *tsk,
+		const struct stacktrace_ops *ops,
+		void *data)
+{
+	int reliable = 0;
+	unsigned long *sp, bp, addr;
+	struct pt_regs *segv_regs = tsk->thread.segv_regs;
+	struct stack_frame *frame;
+
+	bp = get_frame_pointer(tsk, segv_regs);
+	sp = get_stack_pointer(tsk, segv_regs);
+
+	frame = (struct stack_frame *)bp;
+	while (((long) sp & (THREAD_SIZE-1)) != 0) {
+		addr = *sp;
+		if (__kernel_text_address(addr)) {
+			reliable = 0;
+			if ((unsigned long) sp == bp + sizeof(long)) {
+				frame = frame ? frame->next_frame : NULL;
+				bp = (unsigned long)frame;
+				reliable = 1;
+			}
+			ops->address(data, addr, reliable);
+		}
+		sp++;
+	}
+}
+
+static void save_addr(void *data, unsigned long address, int reliable)
+{
+	struct stack_trace *trace = data;
+
+	if (!reliable)
+		return;
+	if (trace->nr_entries >= trace->max_entries)
+		return;
+
+	trace->entries[trace->nr_entries++] = address;
+}
+
+static const struct stacktrace_ops dump_ops = {
+	.address = save_addr
+};
+
+static void __save_stack_trace(struct task_struct *tsk, struct stack_trace *trace)
+{
+	dump_trace(tsk, &dump_ops, trace);
+	if (trace->nr_entries < trace->max_entries)
+		trace->entries[trace->nr_entries++] = ULONG_MAX;
+}
+
+void save_stack_trace(struct stack_trace *trace)
+{
+	__save_stack_trace(current, trace);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace);
+
+void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
+{
+	__save_stack_trace(tsk, trace);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
diff --git a/arch/um/kernel/sysrq.c b/arch/um/kernel/sysrq.c
index 799d7e413bf5..894c8d303cda 100644
--- a/arch/um/kernel/sysrq.c
+++ b/arch/um/kernel/sysrq.c
@@ -12,57 +12,20 @@
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <asm/sysrq.h>
+#include <asm/stacktrace.h>
 #include <os.h>
 
-struct stack_frame {
-	struct stack_frame *next_frame;
-	unsigned long return_address;
-};
-
-static void do_stack_trace(unsigned long *sp, unsigned long bp)
+static void _print_addr(void *data, unsigned long address, int reliable)
 {
-	int reliable;
-	unsigned long addr;
-	struct stack_frame *frame = (struct stack_frame *)bp;
-
-	printk(KERN_INFO "Call Trace:\n");
-	while (((long) sp & (THREAD_SIZE-1)) != 0) {
-		addr = *sp;
-		if (__kernel_text_address(addr)) {
-			reliable = 0;
-			if ((unsigned long) sp == bp + sizeof(long)) {
-				frame = frame ? frame->next_frame : NULL;
-				bp = (unsigned long)frame;
-				reliable = 1;
-			}
-
-			printk(KERN_INFO " [<%08lx>]", addr);
-			printk(KERN_CONT " %s", reliable ? "" : "? ");
-			print_symbol(KERN_CONT "%s", addr);
-			printk(KERN_CONT "\n");
-		}
-		sp++;
-	}
-	printk(KERN_INFO "\n");
+	pr_info(" [<%08lx>]", address);
+	pr_cont(" %s", reliable ? "" : "? ");
+	print_symbol("%s", address);
+	pr_cont("\n");
 }
 
-static unsigned long get_frame_pointer(struct task_struct *task,
-				       struct pt_regs *segv_regs)
-{
-	if (!task || task == current)
-		return segv_regs ? PT_REGS_BP(segv_regs) : current_bp();
-	else
-		return KSTK_EBP(task);
-}
-
-static unsigned long *get_stack_pointer(struct task_struct *task,
-					struct pt_regs *segv_regs)
-{
-	if (!task || task == current)
-		return segv_regs ? (unsigned long *)PT_REGS_SP(segv_regs) : current_sp();
-	else
-		return (unsigned long *)KSTK_ESP(task);
-}
+static const struct stacktrace_ops stackops = {
+	.address = _print_addr
+};
 
 void show_stack(struct task_struct *task, unsigned long *stack)
 {
@@ -71,7 +34,7 @@ void show_stack(struct task_struct *task, unsigned long *stack)
 	int i;
 
 	if (!segv_regs && os_is_signal_stack()) {
-		printk(KERN_ERR "Received SIGSEGV in SIGSEGV handler,"
+		pr_err("Received SIGSEGV in SIGSEGV handler,"
 				" aborting stack trace!\n");
 		return;
 	}
@@ -83,16 +46,18 @@ void show_stack(struct task_struct *task, unsigned long *stack)
 	if (!stack)
 		sp = get_stack_pointer(task, segv_regs);
 
-	printk(KERN_INFO "Stack:\n");
+	pr_info("Stack:\n");
 	stack = sp;
 	for (i = 0; i < 3 * STACKSLOTS_PER_LINE; i++) {
 		if (kstack_end(stack))
 			break;
 		if (i && ((i % STACKSLOTS_PER_LINE) == 0))
-			printk(KERN_CONT "\n");
-		printk(KERN_CONT " %08lx", *stack++);
+			pr_cont("\n");
+		pr_cont(" %08lx", *stack++);
 	}
-	printk(KERN_CONT "\n");
+	pr_cont("\n");
 
-	do_stack_trace(sp, bp);
+	pr_info("Call Trace:\n");
+	dump_trace(current, &stackops, NULL);
+	pr_info("\n");
 }
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 016adf0985d5..9274eae6ae7b 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -348,12 +348,7 @@ int __init linux_main(int argc, char **argv)
 	start_vm = VMALLOC_START;
 
 	setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem);
-	if (init_maps(physmem_size, iomem_size, highmem)) {
-		printf("Failed to allocate mem_map for %Lu bytes of physical "
-		       "memory and %Lu bytes of highmem\n", physmem_size,
-		       highmem);
-		exit(1);
-	}
+	mem_total_pages(physmem_size, iomem_size, highmem);
 
 	virtmem_size = physmem_size;
 	stack = (unsigned long) argv;