x86/bugs: Expose x86_spec_ctrl_base directly

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

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index b474c8de7fba09cfe27d1e0124f694d152654570..8da06a5485ccdf1715e18e968af04e2cc8c2910f 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -77,6 +77,9 @@
 #include <asm/i8259.h>
 #include <asm/realmode.h>
 #include <asm/misc.h>
+#include <asm/spec-ctrl.h>
+#include <asm/microcode.h>
+#include <asm/spec-ctrl.h>
 
 /* Number of siblings per CPU package */
 int smp_num_siblings = 1;
@@ -128,25 +131,16 @@ static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
        spin_lock_irqsave(&rtc_lock, flags);
        CMOS_WRITE(0xa, 0xf);
        spin_unlock_irqrestore(&rtc_lock, flags);
-       local_flush_tlb();
-       pr_debug("1.\n");
        *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_HIGH)) =
                                                        start_eip >> 4;
-       pr_debug("2.\n");
        *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) =
                                                        start_eip & 0xf;
-       pr_debug("3.\n");
 }
 
 static inline void smpboot_restore_warm_reset_vector(void)
 {
        unsigned long flags;
 
-       /*
-        * Install writable page 0 entry to set BIOS data area.
-        */
-       local_flush_tlb();
-
        /*
         * Paranoid:  Set warm reset code and vector here back
         * to default values.
@@ -193,6 +187,12 @@ static void smp_callin(void)
         */
        smp_store_cpu_info(cpuid);
 
+       /*
+        * The topology information must be up to date before
+        * calibrate_delay() and notify_cpu_starting().
+        */
+       set_cpu_sibling_map(raw_smp_processor_id());
+
        /*
         * Get our bogomips.
         * Update loops_per_jiffy in cpu_data. Previous call to
@@ -203,11 +203,6 @@ static void smp_callin(void)
        cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
        pr_debug("Stack at about %p\n", &cpuid);
 
-       /*
-        * This must be done before setting cpu_online_mask
-        * or calling notify_cpu_starting.
-        */
-       set_cpu_sibling_map(raw_smp_processor_id());
        wmb();
 
        notify_cpu_starting(cpuid);
@@ -226,10 +221,12 @@ static int enable_start_cpu0;
 static void notrace start_secondary(void *unused)
 {
        /*
-        * Don't put *anything* before cpu_init(), SMP booting is too
-        * fragile that we want to limit the things done here to the
-        * most necessary things.
+        * Don't put *anything* except direct CPU state initialization
+        * before cpu_init(), SMP booting is too fragile that we want to
+        * limit the things done here to the most necessary things.
         */
+       if (IS_ENABLED(CONFIG_X86_64) && boot_cpu_has(X86_FEATURE_PCID))
+               __write_cr4(__read_cr4() | X86_CR4_PCIDE);
        cpu_init();
        x86_cpuinit.early_percpu_clock_init();
        preempt_disable();
@@ -250,6 +247,8 @@ static void notrace start_secondary(void *unused)
         */
        check_tsc_sync_target();
 
+       speculative_store_bypass_ht_init();
+
        /*
         * Lock vector_lock and initialize the vectors on this cpu
         * before setting the cpu online. We must set it online with
@@ -958,8 +957,7 @@ void common_cpu_up(unsigned int cpu, struct task_struct *idle)
 #ifdef CONFIG_X86_32
        /* Stack for startup_32 can be just as for start_secondary onwards */
        irq_ctx_init(cpu);
-       per_cpu(cpu_current_top_of_stack, cpu) =
-               (unsigned long)task_stack_page(idle) + THREAD_SIZE;
+       per_cpu(cpu_current_top_of_stack, cpu) = task_top_of_stack(idle);
 #else
        initial_gs = per_cpu_offset(cpu);
 #endif
@@ -971,7 +969,8 @@ void common_cpu_up(unsigned int cpu, struct task_struct *idle)
  * Returns zero if CPU booted OK, else error code from
  * ->wakeup_secondary_cpu.
  */
-static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
+static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle,
+                      int *cpu0_nmi_registered)
 {
        volatile u32 *trampoline_status =
                (volatile u32 *) __va(real_mode_header->trampoline_status);
@@ -979,7 +978,6 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
        unsigned long start_ip = real_mode_header->trampoline_start;
 
        unsigned long boot_error = 0;
-       int cpu0_nmi_registered = 0;
        unsigned long timeout;
 
        idle->thread.sp = (unsigned long)task_pt_regs(idle);
@@ -987,12 +985,8 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
        initial_code = (unsigned long)start_secondary;
        initial_stack  = idle->thread.sp;
 
-       /*
-        * Enable the espfix hack for this CPU
-       */
-#ifdef CONFIG_X86_ESPFIX64
+       /* Enable the espfix hack for this CPU */
        init_espfix_ap(cpu);
-#endif
 
        /* So we see what's up */
        announce_cpu(cpu, apicid);
@@ -1035,7 +1029,7 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
                boot_error = apic->wakeup_secondary_cpu(apicid, start_ip);
        else
                boot_error = wakeup_cpu_via_init_nmi(cpu, start_ip, apicid,
-                                                    &cpu0_nmi_registered);
+                                                    cpu0_nmi_registered);
 
        if (!boot_error) {
                /*
@@ -1080,12 +1074,6 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
                 */
                smpboot_restore_warm_reset_vector();
        }
-       /*
-        * Clean up the nmi handler. Do this after the callin and callout sync
-        * to avoid impact of possible long unregister time.
-        */
-       if (cpu0_nmi_registered)
-               unregister_nmi_handler(NMI_LOCAL, "wake_cpu0");
 
        return boot_error;
 }
@@ -1093,8 +1081,9 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
 int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
 {
        int apicid = apic->cpu_present_to_apicid(cpu);
+       int cpu0_nmi_registered = 0;
        unsigned long flags;
-       int err;
+       int err, ret = 0;
 
        WARN_ON(irqs_disabled());
 
@@ -1131,10 +1120,11 @@ int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
 
        common_cpu_up(cpu, tidle);
 
-       err = do_boot_cpu(apicid, cpu, tidle);
+       err = do_boot_cpu(apicid, cpu, tidle, &cpu0_nmi_registered);
        if (err) {
                pr_err("do_boot_cpu failed(%d) to wakeup CPU#%u\n", err, cpu);
-               return -EIO;
+               ret = -EIO;
+               goto unreg_nmi;
        }
 
        /*
@@ -1150,7 +1140,15 @@ int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
                touch_nmi_watchdog();
        }
 
-       return 0;
+unreg_nmi:
+       /*
+        * Clean up the nmi handler. Do this after the callin and callout sync
+        * to avoid impact of possible long unregister time.
+        */
+       if (cpu0_nmi_registered)
+               unregister_nmi_handler(NMI_LOCAL, "wake_cpu0");
+
+       return ret;
 }
 
 /**
@@ -1355,6 +1353,8 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus)
        set_mtrr_aps_delayed_init();
 
        smp_quirk_init_udelay();
+
+       speculative_store_bypass_ht_init();
 }
 
 void arch_enable_nonboot_cpus_begin(void)
@@ -1699,9 +1699,15 @@ void native_play_dead(void)
        play_dead_common();
        tboot_shutdown(TB_SHUTDOWN_WFS);
 
+       if (ibrs_inuse)
+               native_wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+
        mwait_play_dead();      /* Only returns on failure */
        if (cpuidle_play_dead())
                hlt_play_dead();
+
+       if (ibrs_inuse)
+               native_wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base | SPEC_CTRL_IBRS);
 }
 
 #else /* ... !CONFIG_HOTPLUG_CPU */