[PATCH 05/16] x86: cpu common make 32bit have 64bit only funcs

Yinghai Lu
2008-09-05T03:10:52Z

arch/x86/kernel/cpu/common.c | 138 +++++++++++++++++++++++++++++++++++++++
arch/x86/kernel/cpu/common_64.c | 12 ++++
2 files changed, 150 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 9128ba0..dcd3ebd 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -750,6 +750,143 @@ __setup("clearcpuid=", setup_disablecpuid);

cpumask_t cpu_initialized __cpuinitdata = CPU_MASK_NONE;

+#ifdef CONFIG_X86_64
+struct x8664_pda **_cpu_pda __read_mostly;
+EXPORT_SYMBOL(_cpu_pda);
+
+struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table };
+
+char boot_cpu_stack[IRQSTACKSIZE] __page_aligned_bss;
+
+unsigned long __supported_pte_mask __read_mostly = ~0UL;
+EXPORT_SYMBOL_GPL(__supported_pte_mask);
+
+static int do_not_nx __cpuinitdata;
+
+/* noexec=on|off
+Control non executable mappings for 64bit processes.
+
+on Enable(default)
+off Disable
+*/
+static int __init nonx_setup(char *str)
+{
+ if (!str)
+ return -EINVAL;
+ if (!strncmp(str, "on", 2)) {
+ __supported_pte_mask |= _PAGE_NX;
+ do_not_nx = 0;
+ } else if (!strncmp(str, "off", 3)) {
+ do_not_nx = 1;
+ __supported_pte_mask &= ~_PAGE_NX;
+ }
+ return 0;
+}
+early_param("noexec", nonx_setup);
+
+int force_personality32;
+
+/* noexec32=on|off
+Control non executable heap for 32bit processes.
+To control the stack too use noexec=off
+
+on PROT_READ does not imply PROT_EXEC for 32bit processes (default)
+off PROT_READ implies PROT_EXEC
+*/
+static int __init nonx32_setup(char *str)
+{
+ if (!strcmp(str, "on"))
+ force_personality32 &= ~READ_IMPLIES_EXEC;
+ else if (!strcmp(str, "off"))
+ force_personality32 |= READ_IMPLIES_EXEC;
+ return 1;
+}
+__setup("noexec32=", nonx32_setup);
+
+void pda_init(int cpu)
+{
+ struct x8664_pda *pda = cpu_pda(cpu);
+
+ /* Setup up data that may be needed in __get_free_pages early */
+ loadsegment(fs, 0);
+ loadsegment(gs, 0);
+ /* Memory clobbers used to order PDA accessed */
+ mb();
+ wrmsrl(MSR_GS_BASE, pda);
+ mb();
+
+ pda->cpunumber = cpu;
+ pda->irqcount = -1;
+ pda->kernelstack = (unsigned long)stack_thread_info() -
+ PDA_STACKOFFSET + THREAD_SIZE;
+ pda->active_mm = &init_mm;
+ pda->mmu_state = 0;
+
+ if (cpu == 0) {
+ /* others are initialized in smpboot.c */
+ pda->pcurrent = &init_task;
+ pda->irqstackptr = boot_cpu_stack;
+ pda->irqstackptr += IRQSTACKSIZE - 64;
+ } else {
+ if (!pda->irqstackptr) {
+ pda->irqstackptr = (char *)
+ __get_free_pages(GFP_ATOMIC, IRQSTACK_ORDER);
+ if (!pda->irqstackptr)
+ panic("cannot allocate irqstack for cpu %d",
+ cpu);
+ pda->irqstackptr += IRQSTACKSIZE - 64;
+ }
+
+ if (pda->nodenumber == 0 && cpu_to_node(cpu) != NUMA_NO_NODE)
+ pda->nodenumber = cpu_to_node(cpu);
+ }
+}
+
+char boot_exception_stacks[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ +
+ DEBUG_STKSZ] __page_aligned_bss;
+
+extern asmlinkage void ignore_sysret(void);
+
+/* May not be marked __init: used by software suspend */
+void syscall_init(void)
+{
+ /*
+ * LSTAR and STAR live in a bit strange symbiosis.
+ * They both write to the same internal register. STAR allows to
+ * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
+ */
+ wrmsrl(MSR_STAR, ((u64)__USER32_CS)<<48 | ((u64)__KERNEL_CS)<<32);
+ wrmsrl(MSR_LSTAR, system_call);
+ wrmsrl(MSR_CSTAR, ignore_sysret);
+
+#ifdef CONFIG_IA32_EMULATION
+ syscall32_cpu_init();
+#endif
+
+ /* Flags to clear on syscall */
+ wrmsrl(MSR_SYSCALL_MASK,
+ X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|X86_EFLAGS_IOPL);
+}
+
+void __cpuinit check_efer(void)
+{
+ unsigned long efer;
+
+ rdmsrl(MSR_EFER, efer);
+ if (!(efer & EFER_NX) || do_not_nx)
+ __supported_pte_mask &= ~_PAGE_NX;
+}
+
+unsigned long kernel_eflags;
+
+/*
+ * Copies of the original ist values from the tss are only accessed during
+ * debugging, no special alignment required.
+ */
+DEFINE_PER_CPU(struct orig_ist, orig_ist);
+
+#else
+
/* Make sure %fs is initialized properly in idle threads */
struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
{
@@ -757,6 +894,7 @@ struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
regs->fs = __KERNEL_PERCPU;
return regs;
}
+#endif

/*
* cpu_init() initializes state that is per-CPU. Some data is already
diff --git a/arch/x86/kernel/cpu/common_64.c b/arch/x86/kernel/cpu/common_64.c
index 40c9d89..9f2a6ec 100644
--- a/arch/x86/kernel/cpu/common_64.c
+++ b/arch/x86/kernel/cpu/common_64.c
@@ -704,6 +704,7 @@ __setup("clearcpuid=", setup_disablecpuid);

cpumask_t cpu_initialized __cpuinitdata = CPU_MASK_NONE;

+#ifdef CONFIG_X86_64
struct x8664_pda **_cpu_pda __read_mostly;
EXPORT_SYMBOL(_cpu_pda);

@@ -838,6 +839,17 @@ unsigned long kernel_eflags;
*/
DEFINE_PER_CPU(struct orig_ist, orig_ist);

+#else
+
+/* Make sure %fs is initialized properly in idle threads */
+struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
+{
+ memset(regs, 0, sizeof(struct pt_regs));
+ regs->fs = __KERNEL_PERCPU;
+ return regs;
+}
+#endif
+
/*
* cpu_init() initializes state that is per-CPU. Some data is already
* initialized (naturally) in the bootstrap process, such as the GDT
--
1.5.4.5