1 files changed, 163 insertions, 63 deletions

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 93b658248d01..4806cc28d7ca 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -49,6 +49,7 @@
 #include <xen/hvc-console.h>
 #include <xen/acpi.h>
 
+#include <asm/cpuid/api.h>
 #include <asm/paravirt.h>
 #include <asm/apic.h>
 #include <asm/page.h>
@@ -60,6 +61,7 @@
 #include <asm/processor.h>
 #include <asm/proto.h>
 #include <asm/msr-index.h>
+#include <asm/msr.h>
 #include <asm/traps.h>
 #include <asm/setup.h>
 #include <asm/desc.h>
@@ -72,6 +74,7 @@
 #include <asm/mwait.h>
 #include <asm/pci_x86.h>
 #include <asm/cpu.h>
+#include <asm/irq_stack.h>
 #ifdef CONFIG_X86_IOPL_IOPERM
 #include <asm/io_bitmap.h>
 #endif
@@ -79,16 +82,12 @@
 #ifdef CONFIG_ACPI
 #include <linux/acpi.h>
 #include <asm/acpi.h>
-#include <acpi/pdc_intel.h>
+#include <acpi/proc_cap_intel.h>
 #include <acpi/processor.h>
 #include <xen/interface/platform.h>
 #endif
 
 #include "xen-ops.h"
-#include "mmu.h"
-#include "smp.h"
-#include "multicalls.h"
-#include "pmu.h"
 
 #include "../kernel/cpu/cpu.h" /* get_cpu_cap() */
 
@@ -97,10 +96,58 @@ void *xen_initial_gdt;
 static int xen_cpu_up_prepare_pv(unsigned int cpu);
 static int xen_cpu_dead_pv(unsigned int cpu);
 
+#ifndef CONFIG_PREEMPTION
+/*
+ * Some hypercalls issued by the toolstack can take many 10s of
+ * seconds. Allow tasks running hypercalls via the privcmd driver to
+ * be voluntarily preempted even if full kernel preemption is
+ * disabled.
+ *
+ * Such preemptible hypercalls are bracketed by
+ * xen_preemptible_hcall_begin() and xen_preemptible_hcall_end()
+ * calls.
+ */
+DEFINE_PER_CPU(bool, xen_in_preemptible_hcall);
+EXPORT_SYMBOL_GPL(xen_in_preemptible_hcall);
+
+/*
+ * In case of scheduling the flag must be cleared and restored after
+ * returning from schedule as the task might move to a different CPU.
+ */
+static __always_inline bool get_and_clear_inhcall(void)
+{
+	bool inhcall = __this_cpu_read(xen_in_preemptible_hcall);
+
+	__this_cpu_write(xen_in_preemptible_hcall, false);
+	return inhcall;
+}
+
+static __always_inline void restore_inhcall(bool inhcall)
+{
+	__this_cpu_write(xen_in_preemptible_hcall, inhcall);
+}
+
+#else
+
+static __always_inline bool get_and_clear_inhcall(void) { return false; }
+static __always_inline void restore_inhcall(bool inhcall) { }
+
+#endif
+
 struct tls_descs {
 	struct desc_struct desc[3];
 };
 
+DEFINE_PER_CPU(enum xen_lazy_mode, xen_lazy_mode) = XEN_LAZY_NONE;
+
+enum xen_lazy_mode xen_get_lazy_mode(void)
+{
+	if (in_interrupt())
+		return XEN_LAZY_NONE;
+
+	return this_cpu_read(xen_lazy_mode);
+}
+
 /*
  * Updating the 3 TLS descriptors in the GDT on every task switch is
  * surprisingly expensive so we avoid updating them if they haven't
@@ -164,7 +211,7 @@ static void __init xen_set_mtrr_data(void)
 
 	/* Only overwrite MTRR state if any MTRR could be got from Xen. */
 	if (reg)
-		mtrr_overwrite_state(var, reg, MTRR_TYPE_UNCACHABLE);
+		guest_force_mtrr_state(var, reg, MTRR_TYPE_UNCACHABLE);
 #endif
 }
 
@@ -188,7 +235,10 @@ static void __init xen_pv_init_platform(void)
 	if (xen_initial_domain())
 		xen_set_mtrr_data();
 	else
-		mtrr_overwrite_state(NULL, 0, MTRR_TYPE_WRBACK);
+		guest_force_mtrr_state(NULL, 0, MTRR_TYPE_WRBACK);
+
+	/* Adjust nr_cpu_ids before "enumeration" happens */
+	xen_smp_count_cpus();
 }
 
 static void __init xen_pv_guest_late_init(void)
@@ -205,14 +255,22 @@ static __read_mostly unsigned int cpuid_leaf5_edx_val;
 static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 		      unsigned int *cx, unsigned int *dx)
 {
-	unsigned maskebx = ~0;
+	unsigned int maskebx = ~0;
+	unsigned int or_ebx = 0;
 
 	/*
 	 * Mask out inconvenient features, to try and disable as many
 	 * unsupported kernel subsystems as possible.
 	 */
 	switch (*ax) {
-	case CPUID_MWAIT_LEAF:
+	case 0x1:
+		/* Replace initial APIC ID in bits 24-31 of EBX. */
+		/* See xen_pv_smp_config() for related topology preparations. */
+		maskebx = 0x00ffffff;
+		or_ebx = smp_processor_id() << 24;
+		break;
+
+	case CPUID_LEAF_MWAIT:
 		/* Synthesize the values.. */
 		*ax = 0;
 		*bx = 0;
@@ -234,6 +292,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 		: "0" (*ax), "2" (*cx));
 
 	*bx &= maskebx;
+	*bx |= or_ebx;
 }
 
 static bool __init xen_check_mwait(void)
@@ -281,24 +340,24 @@ static bool __init xen_check_mwait(void)
 	 * ecx and edx. The hypercall provides only partial information.
 	 */
 
-	ax = CPUID_MWAIT_LEAF;
+	ax = CPUID_LEAF_MWAIT;
 	bx = 0;
 	cx = 0;
 	dx = 0;
 
 	native_cpuid(&ax, &bx, &cx, &dx);
 
-	/* Ask the Hypervisor whether to clear ACPI_PDC_C_C2C3_FFH. If so,
+	/* Ask the Hypervisor whether to clear ACPI_PROC_CAP_C_C2C3_FFH. If so,
 	 * don't expose MWAIT_LEAF and let ACPI pick the IOPORT version of C3.
 	 */
 	buf[0] = ACPI_PDC_REVISION_ID;
 	buf[1] = 1;
-	buf[2] = (ACPI_PDC_C_CAPABILITY_SMP | ACPI_PDC_EST_CAPABILITY_SWSMP);
+	buf[2] = (ACPI_PROC_CAP_C_CAPABILITY_SMP | ACPI_PROC_CAP_EST_CAPABILITY_SWSMP);
 
 	set_xen_guest_handle(op.u.set_pminfo.pdc, buf);
 
 	if ((HYPERVISOR_platform_op(&op) == 0) &&
-	    (buf[2] & (ACPI_PDC_C_C1_FFH | ACPI_PDC_C_C2C3_FFH))) {
+	    (buf[2] & (ACPI_PROC_CAP_C_C1_FFH | ACPI_PROC_CAP_C_C2C3_FFH))) {
 		cpuid_leaf5_ecx_val = cx;
 		cpuid_leaf5_edx_val = dx;
 	}
@@ -323,7 +382,6 @@ static bool __init xen_check_xsave(void)
 
 static void __init xen_init_capabilities(void)
 {
-	setup_force_cpu_cap(X86_FEATURE_XENPV);
 	setup_clear_cpu_cap(X86_FEATURE_DCA);
 	setup_clear_cpu_cap(X86_FEATURE_APERFMPERF);
 	setup_clear_cpu_cap(X86_FEATURE_MTRR);
@@ -362,10 +420,25 @@ static noinstr unsigned long xen_get_debugreg(int reg)
 	return HYPERVISOR_get_debugreg(reg);
 }
 
+static void xen_start_context_switch(struct task_struct *prev)
+{
+	BUG_ON(preemptible());
+
+	if (this_cpu_read(xen_lazy_mode) == XEN_LAZY_MMU) {
+		arch_leave_lazy_mmu_mode();
+		set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES);
+	}
+	enter_lazy(XEN_LAZY_CPU);
+}
+
 static void xen_end_context_switch(struct task_struct *next)
 {
+	BUG_ON(preemptible());
+
 	xen_mc_flush();
-	paravirt_end_context_switch(next);
+	leave_lazy(XEN_LAZY_CPU);
+	if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
+		arch_enter_lazy_mmu_mode();
 }
 
 static unsigned long xen_store_tr(void)
@@ -472,7 +545,7 @@ static void xen_set_ldt(const void *addr, unsigned entries)
 
 	MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
 
-	xen_mc_issue(PARAVIRT_LAZY_CPU);
+	xen_mc_issue(XEN_LAZY_CPU);
 }
 
 static void xen_load_gdt(const struct desc_ptr *dtr)
@@ -523,7 +596,7 @@ static void __init xen_load_gdt_boot(const struct desc_ptr *dtr)
 	BUG_ON(size > PAGE_SIZE);
 	BUG_ON(va & ~PAGE_MASK);
 
-	pfn = virt_to_pfn(va);
+	pfn = virt_to_pfn((void *)va);
 	mfn = pfn_to_mfn(pfn);
 
 	pte = pfn_pte(pfn, PAGE_KERNEL_RO);
@@ -568,7 +641,7 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
 	 * exception between the new %fs descriptor being loaded and
 	 * %fs being effectively cleared at __switch_to().
 	 */
-	if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU)
+	if (xen_get_lazy_mode() == XEN_LAZY_CPU)
 		loadsegment(fs, 0);
 
 	xen_mc_batch();
@@ -577,7 +650,7 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
 	load_TLS_descriptor(t, cpu, 1);
 	load_TLS_descriptor(t, cpu, 2);
 
-	xen_mc_issue(PARAVIRT_LAZY_CPU);
+	xen_mc_issue(XEN_LAZY_CPU);
 }
 
 static void xen_load_gs_index(unsigned int idx)
@@ -652,6 +725,36 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_machine_check)
 }
 #endif
 
+static void __xen_pv_evtchn_do_upcall(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	inc_irq_stat(irq_hv_callback_count);
+
+	xen_evtchn_do_upcall();
+
+	set_irq_regs(old_regs);
+}
+
+__visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
+{
+	irqentry_state_t state = irqentry_enter(regs);
+	bool inhcall;
+
+	instrumentation_begin();
+	run_sysvec_on_irqstack_cond(__xen_pv_evtchn_do_upcall, regs);
+
+	inhcall = get_and_clear_inhcall();
+	if (inhcall && !WARN_ON_ONCE(state.exit_rcu)) {
+		irqentry_exit_cond_resched();
+		instrumentation_end();
+		restore_inhcall(inhcall);
+	} else {
+		instrumentation_end();
+		irqentry_exit(regs, state);
+	}
+}
+
 struct trap_array_entry {
 	void (*orig)(void);
 	void (*xen)(void);
@@ -678,7 +781,7 @@ static struct trap_array_entry trap_array[] = {
 	TRAP_ENTRY(exc_int3,				false ),
 	TRAP_ENTRY(exc_overflow,			false ),
 #ifdef CONFIG_IA32_EMULATION
-	{ entry_INT80_compat,          xen_entry_INT80_compat,          false },
+	TRAP_ENTRY(int80_emulation,			false ),
 #endif
 	TRAP_ENTRY(exc_page_fault,			false ),
 	TRAP_ENTRY(exc_divide_error,			false ),
@@ -694,7 +797,7 @@ static struct trap_array_entry trap_array[] = {
 	TRAP_ENTRY(exc_coprocessor_error,		false ),
 	TRAP_ENTRY(exc_alignment_check,			false ),
 	TRAP_ENTRY(exc_simd_coprocessor_error,		false ),
-#ifdef CONFIG_X86_KERNEL_IBT
+#ifdef CONFIG_X86_CET
 	TRAP_ENTRY(exc_control_protection,		false ),
 #endif
 };
@@ -909,7 +1012,7 @@ static void xen_load_sp0(unsigned long sp0)
 
 	mcs = xen_mc_entry(0);
 	MULTI_stack_switch(mcs.mc, __KERNEL_DS, sp0);
-	xen_mc_issue(PARAVIRT_LAZY_CPU);
+	xen_mc_issue(XEN_LAZY_CPU);
 	this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
 }
 
@@ -973,7 +1076,7 @@ static void xen_write_cr0(unsigned long cr0)
 
 	MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
 
-	xen_mc_issue(PARAVIRT_LAZY_CPU);
+	xen_mc_issue(XEN_LAZY_CPU);
 }
 
 static void xen_write_cr4(unsigned long cr4)
@@ -983,37 +1086,33 @@ static void xen_write_cr4(unsigned long cr4)
 	native_write_cr4(cr4);
 }
 
-static u64 xen_do_read_msr(unsigned int msr, int *err)
+static u64 xen_do_read_msr(u32 msr, int *err)
 {
 	u64 val = 0;	/* Avoid uninitialized value for safe variant. */
 
-	if (pmu_msr_read(msr, &val, err))
+	if (pmu_msr_chk_emulated(msr, &val, true))
 		return val;
 
 	if (err)
-		val = native_read_msr_safe(msr, err);
+		*err = native_read_msr_safe(msr, &val);
 	else
 		val = native_read_msr(msr);
 
 	switch (msr) {
 	case MSR_IA32_APICBASE:
 		val &= ~X2APIC_ENABLE;
+		if (smp_processor_id() == 0)
+			val |= MSR_IA32_APICBASE_BSP;
+		else
+			val &= ~MSR_IA32_APICBASE_BSP;
 		break;
 	}
 	return val;
 }
 
-static void set_seg(unsigned int which, unsigned int low, unsigned int high,
-		    int *err)
+static void set_seg(u32 which, u64 base)
 {
-	u64 base = ((u64)high << 32) | low;
-
-	if (HYPERVISOR_set_segment_base(which, base) == 0)
-		return;
-
-	if (err)
-		*err = -EIO;
-	else
+	if (HYPERVISOR_set_segment_base(which, base))
 		WARN(1, "Xen set_segment_base(%u, %llx) failed\n", which, base);
 }
 
@@ -1022,20 +1121,19 @@ static void set_seg(unsigned int which, unsigned int low, unsigned int high,
  * With err == NULL write_msr() semantics are selected.
  * Supplying an err pointer requires err to be pre-initialized with 0.
  */
-static void xen_do_write_msr(unsigned int msr, unsigned int low,
-			     unsigned int high, int *err)
+static void xen_do_write_msr(u32 msr, u64 val, int *err)
 {
 	switch (msr) {
 	case MSR_FS_BASE:
-		set_seg(SEGBASE_FS, low, high, err);
+		set_seg(SEGBASE_FS, val);
 		break;
 
 	case MSR_KERNEL_GS_BASE:
-		set_seg(SEGBASE_GS_USER, low, high, err);
+		set_seg(SEGBASE_GS_USER, val);
 		break;
 
 	case MSR_GS_BASE:
-		set_seg(SEGBASE_GS_KERNEL, low, high, err);
+		set_seg(SEGBASE_GS_KERNEL, val);
 		break;
 
 	case MSR_STAR:
@@ -1051,42 +1149,45 @@ static void xen_do_write_msr(unsigned int msr, unsigned int low,
 		break;
 
 	default:
-		if (!pmu_msr_write(msr, low, high, err)) {
-			if (err)
-				*err = native_write_msr_safe(msr, low, high);
-			else
-				native_write_msr(msr, low, high);
-		}
+		if (pmu_msr_chk_emulated(msr, &val, false))
+			return;
+
+		if (err)
+			*err = native_write_msr_safe(msr, val);
+		else
+			native_write_msr(msr, val);
 	}
 }
 
-static u64 xen_read_msr_safe(unsigned int msr, int *err)
+static int xen_read_msr_safe(u32 msr, u64 *val)
 {
-	return xen_do_read_msr(msr, err);
+	int err = 0;
+
+	*val = xen_do_read_msr(msr, &err);
+	return err;
 }
 
-static int xen_write_msr_safe(unsigned int msr, unsigned int low,
-			      unsigned int high)
+static int xen_write_msr_safe(u32 msr, u64 val)
 {
 	int err = 0;
 
-	xen_do_write_msr(msr, low, high, &err);
+	xen_do_write_msr(msr, val, &err);
 
 	return err;
 }
 
-static u64 xen_read_msr(unsigned int msr)
+static u64 xen_read_msr(u32 msr)
 {
-	int err;
+	int err = 0;
 
 	return xen_do_read_msr(msr, xen_msr_safe ? &err : NULL);
 }
 
-static void xen_write_msr(unsigned int msr, unsigned low, unsigned high)
+static void xen_write_msr(u32 msr, u64 val)
 {
 	int err;
 
-	xen_do_write_msr(msr, low, high, xen_msr_safe ? &err : NULL);
+	xen_do_write_msr(msr, val, xen_msr_safe ? &err : NULL);
 }
 
 /* This is called once we have the cpu_possible_mask */
@@ -1123,8 +1224,6 @@ static const typeof(pv_ops) xen_cpu_ops __initconst = {
 
 		.write_cr4 = xen_write_cr4,
 
-		.wbinvd = pv_native_wbinvd,
-
 		.read_msr = xen_read_msr,
 		.write_msr = xen_write_msr,
 
@@ -1156,7 +1255,7 @@ static const typeof(pv_ops) xen_cpu_ops __initconst = {
 #endif
 		.io_delay = xen_io_delay,
 
-		.start_context_switch = paravirt_start_context_switch,
+		.start_context_switch = xen_start_context_switch,
 		.end_context_switch = xen_end_context_switch,
 	},
 };
@@ -1302,7 +1401,11 @@ asmlinkage __visible void __init xen_start_kernel(struct start_info *si)
 			JMP32_INSN_SIZE);
 
 	xen_domain_type = XEN_PV_DOMAIN;
+	setup_force_cpu_cap(X86_FEATURE_XENPV);
 	xen_start_flags = xen_start_info->flags;
+	/* Interrupts are guaranteed to be off initially. */
+	early_boot_irqs_disabled = true;
+	static_call_update_early(xen_hypercall, xen_hypercall_pv);
 
 	xen_setup_features();
 
@@ -1326,7 +1429,7 @@ asmlinkage __visible void __init xen_start_kernel(struct start_info *si)
 
 	x86_init.resources.memory_setup = xen_memory_setup;
 	x86_init.irqs.intr_mode_select	= x86_init_noop;
-	x86_init.irqs.intr_mode_init	= x86_init_noop;
+	x86_init.irqs.intr_mode_init	= x86_64_probe_apic;
 	x86_init.oem.arch_setup = xen_arch_setup;
 	x86_init.oem.banner = xen_banner;
 	x86_init.hyper.init_platform = xen_pv_init_platform;
@@ -1366,12 +1469,10 @@ asmlinkage __visible void __init xen_start_kernel(struct start_info *si)
 
 	xen_init_capabilities();
 
-#ifdef CONFIG_X86_LOCAL_APIC
 	/*
 	 * set up the basic apic ops.
 	 */
 	xen_init_apic();
-#endif
 
 	machine_ops = xen_machine_ops;
 
@@ -1395,7 +1496,6 @@ asmlinkage __visible void __init xen_start_kernel(struct start_info *si)
 	WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_pv, xen_cpu_dead_pv));
 
 	local_irq_disable();
-	early_boot_irqs_disabled = true;
 
 	xen_raw_console_write("mapping kernel into physical memory\n");
 	xen_setup_kernel_pagetable((pgd_t *)xen_start_info->pt_base,