x86, vdso: Move syscall and sysenter setup into kernel/cpu/common.c

[mirror_ubuntu-artful-kernel.git] / arch / x86 / kernel / cpu / common.c

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index a135239badb7fd4762ebf939ae755183660641b2..7c65b4666c243300309130b6be9ef5da1f9f0b7b 100644 (file)
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -953,6 +953,38 @@ static void vgetcpu_set_mode(void)
        else
                vgetcpu_mode = VGETCPU_LSL;
 }
+
+/* May not be __init: called during resume */
+static void syscall32_cpu_init(void)
+{
+       /* Load these always in case some future AMD CPU supports
+          SYSENTER from compat mode too. */
+       wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
+       wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
+       wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target);
+
+       wrmsrl(MSR_CSTAR, ia32_cstar_target);
+}
+#endif
+
+#ifdef CONFIG_X86_32
+void enable_sep_cpu(void)
+{
+       int cpu = get_cpu();
+       struct tss_struct *tss = &per_cpu(init_tss, cpu);
+
+       if (!boot_cpu_has(X86_FEATURE_SEP)) {
+               put_cpu();
+               return;
+       }
+
+       tss->x86_tss.ss1 = __KERNEL_CS;
+       tss->x86_tss.sp1 = sizeof(struct tss_struct) + (unsigned long) tss;
+       wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
+       wrmsr(MSR_IA32_SYSENTER_ESP, tss->x86_tss.sp1, 0);
+       wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long) ia32_sysenter_target, 0);
+       put_cpu();
+}
 #endif
 
 void __init identify_boot_cpu(void)