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-rw-r--r--arch/x86/xen/enlighten_pv.c3
-rw-r--r--arch/x86/xen/irq.c2
-rw-r--r--arch/x86/xen/p2m.c5
-rw-r--r--arch/x86/xen/setup.c4
-rw-r--r--arch/x86/xen/smp.h2
-rw-r--r--arch/x86/xen/smp_pv.c17
-rw-r--r--arch/x86/xen/time.c50
-rw-r--r--arch/x86/xen/xen-head.S7
8 files changed, 63 insertions, 27 deletions
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 5b1379662877..bb59cc6ddb2d 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -276,6 +276,7 @@ static void __init xen_init_capabilities(void)
setup_clear_cpu_cap(X86_FEATURE_ACC);
setup_clear_cpu_cap(X86_FEATURE_X2APIC);
setup_clear_cpu_cap(X86_FEATURE_SME);
+ setup_clear_cpu_cap(X86_FEATURE_LKGS);
/*
* Xen PV would need some work to support PCID: CR3 handling as well
@@ -1068,7 +1069,7 @@ static const typeof(pv_ops) xen_cpu_ops __initconst = {
.write_cr4 = xen_write_cr4,
- .wbinvd = native_wbinvd,
+ .wbinvd = pv_native_wbinvd,
.read_msr = xen_read_msr,
.write_msr = xen_write_msr,
diff --git a/arch/x86/xen/irq.c b/arch/x86/xen/irq.c
index 06c3c2fb4b06..6092fea7d651 100644
--- a/arch/x86/xen/irq.c
+++ b/arch/x86/xen/irq.c
@@ -24,7 +24,7 @@ noinstr void xen_force_evtchn_callback(void)
(void)HYPERVISOR_xen_version(0, NULL);
}
-static void xen_safe_halt(void)
+static noinstr void xen_safe_halt(void)
{
/* Blocking includes an implicit local_irq_enable(). */
if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0)
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index 58db86f7b384..9bdc3b656b2c 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -134,11 +134,6 @@ static inline unsigned p2m_mid_index(unsigned long pfn)
return (pfn / P2M_PER_PAGE) % P2M_MID_PER_PAGE;
}
-static inline unsigned p2m_index(unsigned long pfn)
-{
- return pfn % P2M_PER_PAGE;
-}
-
static void p2m_top_mfn_init(unsigned long *top)
{
unsigned i;
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 8db26f10fb1d..c2be3efb2ba0 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -934,12 +934,8 @@ void xen_enable_syscall(void)
static void __init xen_pvmmu_arch_setup(void)
{
- HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
- HYPERVISOR_vm_assist(VMASST_CMD_enable,
- VMASST_TYPE_pae_extended_cr3);
-
if (register_callback(CALLBACKTYPE_event,
xen_asm_exc_xen_hypervisor_callback) ||
register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback))
diff --git a/arch/x86/xen/smp.h b/arch/x86/xen/smp.h
index bd02f9d50107..22fb982ff971 100644
--- a/arch/x86/xen/smp.h
+++ b/arch/x86/xen/smp.h
@@ -21,6 +21,8 @@ void xen_smp_send_reschedule(int cpu);
void xen_smp_send_call_function_ipi(const struct cpumask *mask);
void xen_smp_send_call_function_single_ipi(int cpu);
+void __noreturn xen_cpu_bringup_again(unsigned long stack);
+
struct xen_common_irq {
int irq;
char *name;
diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c
index 6175f2c5c822..a9cf8c8fa074 100644
--- a/arch/x86/xen/smp_pv.c
+++ b/arch/x86/xen/smp_pv.c
@@ -381,21 +381,12 @@ static void xen_pv_cpu_die(unsigned int cpu)
}
}
-static void xen_pv_play_dead(void) /* used only with HOTPLUG_CPU */
+static void __noreturn xen_pv_play_dead(void) /* used only with HOTPLUG_CPU */
{
play_dead_common();
HYPERVISOR_vcpu_op(VCPUOP_down, xen_vcpu_nr(smp_processor_id()), NULL);
- cpu_bringup();
- /*
- * commit 4b0c0f294 (tick: Cleanup NOHZ per cpu data on cpu down)
- * clears certain data that the cpu_idle loop (which called us
- * and that we return from) expects. The only way to get that
- * data back is to call:
- */
- tick_nohz_idle_enter();
- tick_nohz_idle_stop_tick_protected();
-
- cpuhp_online_idle(CPUHP_AP_ONLINE_IDLE);
+ xen_cpu_bringup_again((unsigned long)task_pt_regs(current));
+ BUG();
}
#else /* !CONFIG_HOTPLUG_CPU */
@@ -409,7 +400,7 @@ static void xen_pv_cpu_die(unsigned int cpu)
BUG();
}
-static void xen_pv_play_dead(void)
+static void __noreturn xen_pv_play_dead(void)
{
BUG();
}
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 9ef0a5cca96e..1d597364b49d 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -60,9 +60,17 @@ static u64 xen_clocksource_get_cycles(struct clocksource *cs)
return xen_clocksource_read();
}
-static u64 xen_sched_clock(void)
+static noinstr u64 xen_sched_clock(void)
{
- return xen_clocksource_read() - xen_sched_clock_offset;
+ struct pvclock_vcpu_time_info *src;
+ u64 ret;
+
+ preempt_disable_notrace();
+ src = &__this_cpu_read(xen_vcpu)->time;
+ ret = pvclock_clocksource_read_nowd(src);
+ ret -= xen_sched_clock_offset;
+ preempt_enable_notrace();
+ return ret;
}
static void xen_read_wallclock(struct timespec64 *ts)
@@ -474,15 +482,51 @@ static void xen_setup_vsyscall_time_info(void)
xen_clocksource.vdso_clock_mode = VDSO_CLOCKMODE_PVCLOCK;
}
+/*
+ * Check if it is possible to safely use the tsc as a clocksource. This is
+ * only true if the hypervisor notifies the guest that its tsc is invariant,
+ * the tsc is stable, and the tsc instruction will never be emulated.
+ */
+static int __init xen_tsc_safe_clocksource(void)
+{
+ u32 eax, ebx, ecx, edx;
+
+ if (!(boot_cpu_has(X86_FEATURE_CONSTANT_TSC)))
+ return 0;
+
+ if (!(boot_cpu_has(X86_FEATURE_NONSTOP_TSC)))
+ return 0;
+
+ if (check_tsc_unstable())
+ return 0;
+
+ /* Leaf 4, sub-leaf 0 (0x40000x03) */
+ cpuid_count(xen_cpuid_base() + 3, 0, &eax, &ebx, &ecx, &edx);
+
+ /* tsc_mode = no_emulate (2) */
+ if (ebx != 2)
+ return 0;
+
+ return 1;
+}
+
static void __init xen_time_init(void)
{
struct pvclock_vcpu_time_info *pvti;
int cpu = smp_processor_id();
struct timespec64 tp;
- /* As Dom0 is never moved, no penalty on using TSC there */
+ /*
+ * As Dom0 is never moved, no penalty on using TSC there.
+ *
+ * If it is possible for the guest to determine that the tsc is a safe
+ * clocksource, then set xen_clocksource rating below that of the tsc
+ * so that the system prefers tsc instead.
+ */
if (xen_initial_domain())
xen_clocksource.rating = 275;
+ else if (xen_tsc_safe_clocksource())
+ xen_clocksource.rating = 299;
clocksource_register_hz(&xen_clocksource, NSEC_PER_SEC);
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index ffaa62167f6e..e36ea4268bd2 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -76,6 +76,13 @@ SYM_CODE_START(asm_cpu_bringup_and_idle)
call cpu_bringup_and_idle
SYM_CODE_END(asm_cpu_bringup_and_idle)
+
+SYM_CODE_START(xen_cpu_bringup_again)
+ UNWIND_HINT_FUNC
+ mov %rdi, %rsp
+ UNWIND_HINT_REGS
+ call cpu_bringup_and_idle
+SYM_CODE_END(xen_cpu_bringup_again)
.popsection
#endif
#endif