1 files changed, 27 insertions, 14 deletions

diff --git a/arch/um/sys-i386/tls.c b/arch/um/sys-i386/tls.c
index fcaff86b000c..c6c7131e563b 100644
--- a/arch/um/sys-i386/tls.c
+++ b/arch/um/sys-i386/tls.c
@@ -26,6 +26,11 @@ int do_set_thread_area(struct user_desc *info)
 	cpu = get_cpu();
 	ret = os_set_thread_area(info, userspace_pid[cpu]);
 	put_cpu();
+
+	if (ret)
+		printk(KERN_ERR "PTRACE_SET_THREAD_AREA failed, err = %d, "
+		       "index = %d\n", ret, info->entry_number);
+
 	return ret;
 }
 
@@ -37,6 +42,11 @@ int do_get_thread_area(struct user_desc *info)
 	cpu = get_cpu();
 	ret = os_get_thread_area(info, userspace_pid[cpu]);
 	put_cpu();
+
+	if (ret)
+		printk(KERN_ERR "PTRACE_GET_THREAD_AREA failed, err = %d, "
+		       "index = %d\n", ret, info->entry_number);
+
 	return ret;
 }
 
@@ -172,7 +182,7 @@ void clear_flushed_tls(struct task_struct *task)
  * SKAS patch.
  */
 
-int arch_switch_tls(struct task_struct *from, struct task_struct *to)
+int arch_switch_tls(struct task_struct *to)
 {
 	if (!host_supports_tls)
 		return 0;
@@ -225,7 +235,8 @@ out:
 }
 
 /* XXX: use do_get_thread_area to read the host value? I'm not at all sure! */
-static int get_tls_entry(struct task_struct* task, struct user_desc *info, int idx)
+static int get_tls_entry(struct task_struct *task, struct user_desc *info,
+			 int idx)
 {
 	struct thread_struct *t = &task->thread;
 
@@ -263,7 +274,7 @@ clear:
 	goto out;
 }
 
-asmlinkage int sys_set_thread_area(struct user_desc __user *user_desc)
+int sys_set_thread_area(struct user_desc __user *user_desc)
 {
 	struct user_desc info;
 	int idx, ret;
@@ -298,7 +309,7 @@ asmlinkage int sys_set_thread_area(struct user_desc __user *user_desc)
  * i386. However the only possible error are caused by bugs.
  */
 int ptrace_set_thread_area(struct task_struct *child, int idx,
-		struct user_desc __user *user_desc)
+			   struct user_desc __user *user_desc)
 {
 	struct user_desc info;
 
@@ -311,7 +322,7 @@ int ptrace_set_thread_area(struct task_struct *child, int idx,
 	return set_tls_entry(child, &info, idx, 0);
 }
 
-asmlinkage int sys_get_thread_area(struct user_desc __user *user_desc)
+int sys_get_thread_area(struct user_desc __user *user_desc)
 {
 	struct user_desc info;
 	int idx, ret;
@@ -355,10 +366,9 @@ out:
 	return ret;
 }
 
-
 /*
- * XXX: This part is probably common to i386 and x86-64. Don't create a common
- * file for now, do that when implementing x86-64 support.
+ * This code is really i386-only, but it detects and logs x86_64 GDT indexes
+ * if a 32-bit UML is running on a 64-bit host.
  */
 static int __init __setup_host_supports_tls(void)
 {
@@ -367,13 +377,16 @@ static int __init __setup_host_supports_tls(void)
 		printk(KERN_INFO "Host TLS support detected\n");
 		printk(KERN_INFO "Detected host type: ");
 		switch (host_gdt_entry_tls_min) {
-			case GDT_ENTRY_TLS_MIN_I386:
-				printk("i386\n");
-				break;
-			case GDT_ENTRY_TLS_MIN_X86_64:
-				printk("x86_64\n");
-				break;
+		case GDT_ENTRY_TLS_MIN_I386:
+			printk(KERN_CONT "i386");
+			break;
+		case GDT_ENTRY_TLS_MIN_X86_64:
+			printk(KERN_CONT "x86_64");
+			break;
 		}
+		printk(KERN_CONT " (GDT indexes %d to %d)\n",
+		       host_gdt_entry_tls_min,
+		       host_gdt_entry_tls_min + GDT_ENTRY_TLS_ENTRIES);
 	} else
 		printk(KERN_ERR "  Host TLS support NOT detected! "
 				"TLS support inside UML will not work\n");