---

yaml
---
r: 79736
b: refs/heads/master
c: 77e463d
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 70f5088dd5e9fbd3a71b3a5b01395c676158194b
+refs/heads/master: 77e463d1040d6310211ac5162729f5d4afc4dd8c

trunk/arch/x86/kernel/Makefile_32

@@ -6,7 +6,7 @@ extra-y := head_32.o init_task.o vmlinux.lds
 CPPFLAGS_vmlinux.lds += -Ui386
 
 obj-y	:= process_32.o signal_32.o entry_32.o traps_32.o irq_32.o \
-		ptrace_32.o time_32.o ioport_32.o ldt_32.o setup_32.o i8259_32.o sys_i386_32.o \
+		ptrace_32.o time_32.o ioport_32.o ldt.o setup_32.o i8259_32.o sys_i386_32.o \
 		pci-dma_32.o i386_ksyms_32.o i387_32.o bootflag.o e820_32.o\
 		quirks.o i8237.o topology.o alternative.o i8253.o tsc_32.o io_delay.o
 

trunk/arch/x86/kernel/Makefile_64

@@ -7,7 +7,7 @@ CPPFLAGS_vmlinux.lds += -Ux86_64
 EXTRA_AFLAGS	:= -traditional
 
 obj-y	:= process_64.o signal_64.o entry_64.o traps_64.o irq_64.o \
-		ptrace_64.o time_64.o ioport_64.o ldt_64.o setup_64.o i8259_64.o sys_x86_64.o \
+		ptrace_64.o time_64.o ioport_64.o ldt.o setup_64.o i8259_64.o sys_x86_64.o \
 		x8664_ksyms_64.o i387_64.o syscall_64.o vsyscall_64.o \
 		setup64.o bootflag.o e820_64.o reboot_64.o quirks.o i8237.o \
 		pci-dma_64.o pci-nommu_64.o alternative.o hpet.o tsc_64.o bugs_64.o \

trunk/arch/x86/kernel/ldt_64.c → trunk/arch/x86/kernel/ldt.c

@@ -50,7 +50,11 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
 	oldldt = pc->ldt;
 	memset(newldt + oldsize * LDT_ENTRY_SIZE, 0,
 	       (mincount - oldsize) * LDT_ENTRY_SIZE);
+
+#ifdef CONFIG_X86_64
+	/* CHECKME: Do we really need this ? */
 	wmb();
+#endif
 	pc->ldt = newldt;
 	wmb();
 	pc->size = mincount;
@@ -110,11 +114,18 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
 }
 
 /*
- * Don't touch the LDT register - we're already in the next thread.
+ * No need to lock the MM as we are the last user
+ *
+ * 64bit: Don't touch the LDT register - we're already in the next thread.
  */
 void destroy_context(struct mm_struct *mm)
 {
 	if (mm->context.size) {
+#ifdef CONFIG_X86_32
+		/* CHECKME: Can this ever happen ? */
+		if (mm == current->active_mm)
+			clear_LDT();
+#endif
 		if (mm->context.size * LDT_ENTRY_SIZE > PAGE_SIZE)
 			vfree(mm->context.ldt);
 		else
@@ -159,10 +170,14 @@ static int read_ldt(void __user *ptr, unsigned long bytecount)
 
 static int read_default_ldt(void __user *ptr, unsigned long bytecount)
 {
-	/* Arbitrary number */
-	/* x86-64 default LDT is all zeros */
-	if (bytecount > 128)
-		bytecount = 128;
+	/* CHECKME: Can we use _one_ random number ? */
+#ifdef CONFIG_X86_32
+	unsigned long size = 5 * sizeof(struct desc_struct);
+#else
+	unsigned long size = 128;
+#endif
+	if (bytecount > size)
+		bytecount = size;
 	if (clear_user(ptr, bytecount))
 		return -EFAULT;
 	return bytecount;