-/*
- * Core of Xen paravirt_ops implementation.
- *
- * This file contains the xen_paravirt_ops structure itself, and the
- * implementations for:
- * - privileged instructions
- * - interrupt flags
- * - segment operations
- * - booting and setup
- *
- * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
- */
-
#include <linux/cpu.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/smp.h>
-#include <linux/preempt.h>
-#include <linux/hardirq.h>
-#include <linux/percpu.h>
-#include <linux/delay.h>
-#include <linux/start_kernel.h>
-#include <linux/sched.h>
-#include <linux/kprobes.h>
-#include <linux/bootmem.h>
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/page-flags.h>
-#include <linux/highmem.h>
-#include <linux/console.h>
-#include <linux/pci.h>
-#include <linux/gfp.h>
-#include <linux/memblock.h>
-#include <linux/edd.h>
-#include <linux/frame.h>
-
#include <linux/kexec.h>
-#include <xen/xen.h>
-#include <xen/events.h>
-#include <xen/interface/xen.h>
-#include <xen/interface/version.h>
-#include <xen/interface/physdev.h>
-#include <xen/interface/vcpu.h>
-#include <xen/interface/memory.h>
-#include <xen/interface/nmi.h>
-#include <xen/interface/xen-mca.h>
#include <xen/features.h>
#include <xen/page.h>
-#include <xen/hvc-console.h>
-#include <xen/acpi.h>
-#include <asm/paravirt.h>
-#include <asm/apic.h>
-#include <asm/page.h>
-#include <asm/xen/pci.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
-#include <asm/xen/cpuid.h>
-#include <asm/fixmap.h>
-#include <asm/processor.h>
-#include <asm/proto.h>
-#include <asm/msr-index.h>
-#include <asm/traps.h>
-#include <asm/setup.h>
-#include <asm/desc.h>
-#include <asm/pgalloc.h>
-#include <asm/pgtable.h>
-#include <asm/tlbflush.h>
-#include <asm/reboot.h>
-#include <asm/stackprotector.h>
-#include <asm/hypervisor.h>
-#include <asm/mach_traps.h>
-#include <asm/mwait.h>
-#include <asm/pci_x86.h>
#include <asm/cpu.h>
#include <asm/e820/api.h>
-#ifdef CONFIG_ACPI
-#include <linux/acpi.h>
-#include <asm/acpi.h>
-#include <acpi/pdc_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"
EXPORT_SYMBOL_GPL(hypercall_page);
struct shared_info xen_dummy_shared_info;
-void *xen_initial_gdt;
-
-RESERVE_BRK(shared_info_page_brk, PAGE_SIZE);
-
-static int xen_cpu_up_prepare_pv(unsigned int cpu);
-static int xen_cpu_up_online(unsigned int cpu);
-static int xen_cpu_dead_pv(unsigned int cpu);
-
/*
* Point at some empty memory to start with. We map the real shared_info
* page as soon as fixmap is up and running.
*/
int xen_have_vcpu_info_placement = 1;
-struct tls_descs {
- struct desc_struct desc[3];
-};
+static int xen_cpu_up_online(unsigned int cpu)
+{
+ xen_init_lock_cpu(cpu);
+ return 0;
+}
-/*
- * Updating the 3 TLS descriptors in the GDT on every task switch is
- * surprisingly expensive so we avoid updating them if they haven't
- * changed. Since Xen writes different descriptors than the one
- * passed in the update_descriptor hypercall we keep shadow copies to
- * compare against.
- */
-static DEFINE_PER_CPU(struct tls_descs, shadow_tls_desc);
+int xen_cpuhp_setup(int (*cpu_up_prepare_cb)(unsigned int),
+ int (*cpu_dead_cb)(unsigned int))
+{
+ int rc;
+
+ rc = cpuhp_setup_state_nocalls(CPUHP_XEN_PREPARE,
+ "x86/xen/hvm_guest:prepare",
+ cpu_up_prepare_cb, cpu_dead_cb);
+ if (rc >= 0) {
+ rc = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
+ "x86/xen/hvm_guest:online",
+ xen_cpu_up_online, NULL);
+ if (rc < 0)
+ cpuhp_remove_state_nocalls(CPUHP_XEN_PREPARE);
+ }
+
+ return rc >= 0 ? 0 : rc;
+}
static void clamp_max_cpus(void)
{
}
}
-/*
- * On restore, set the vcpu placement up again.
- * If it fails, then we're in a bad state, since
- * we can't back out from using it...
- */
-void xen_vcpu_restore(void)
+void xen_reboot(int reason)
{
+ struct sched_shutdown r = { .reason = reason };
int cpu;
- for_each_possible_cpu(cpu) {
- bool other_cpu = (cpu != smp_processor_id());
- bool is_up = HYPERVISOR_vcpu_op(VCPUOP_is_up, xen_vcpu_nr(cpu),
- NULL);
-
- if (other_cpu && is_up &&
- HYPERVISOR_vcpu_op(VCPUOP_down, xen_vcpu_nr(cpu), NULL))
- BUG();
-
- xen_setup_runstate_info(cpu);
-
- if (xen_have_vcpu_info_placement)
- xen_vcpu_setup(cpu);
-
- if (other_cpu && is_up &&
- HYPERVISOR_vcpu_op(VCPUOP_up, xen_vcpu_nr(cpu), NULL))
- BUG();
- }
-}
-
-static void __init xen_banner(void)
-{
- unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL);
- struct xen_extraversion extra;
- HYPERVISOR_xen_version(XENVER_extraversion, &extra);
-
- pr_info("Booting paravirtualized kernel %son %s\n",
- xen_feature(XENFEAT_auto_translated_physmap) ?
- "with PVH extensions " : "", pv_info.name);
- printk(KERN_INFO "Xen version: %d.%d%s%s\n",
- version >> 16, version & 0xffff, extra.extraversion,
- xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : "");
-}
-/* Check if running on Xen version (major, minor) or later */
-bool
-xen_running_on_version_or_later(unsigned int major, unsigned int minor)
-{
- unsigned int version;
-
- if (!xen_domain())
- return false;
-
- version = HYPERVISOR_xen_version(XENVER_version, NULL);
- if ((((version >> 16) == major) && ((version & 0xffff) >= minor)) ||
- ((version >> 16) > major))
- return true;
- return false;
-}
-
-#define CPUID_THERM_POWER_LEAF 6
-#define APERFMPERF_PRESENT 0
-
-static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
-static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
-
-static __read_mostly unsigned int cpuid_leaf1_ecx_set_mask;
-static __read_mostly unsigned int cpuid_leaf5_ecx_val;
-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 maskecx = ~0;
- unsigned maskedx = ~0;
- unsigned setecx = 0;
- /*
- * Mask out inconvenient features, to try and disable as many
- * unsupported kernel subsystems as possible.
- */
- switch (*ax) {
- case 1:
- maskecx = cpuid_leaf1_ecx_mask;
- setecx = cpuid_leaf1_ecx_set_mask;
- maskedx = cpuid_leaf1_edx_mask;
- break;
-
- case CPUID_MWAIT_LEAF:
- /* Synthesize the values.. */
- *ax = 0;
- *bx = 0;
- *cx = cpuid_leaf5_ecx_val;
- *dx = cpuid_leaf5_edx_val;
- return;
-
- case CPUID_THERM_POWER_LEAF:
- /* Disabling APERFMPERF for kernel usage */
- maskecx = ~(1 << APERFMPERF_PRESENT);
- break;
-
- case 0xb:
- /* Suppress extended topology stuff */
- maskebx = 0;
- break;
- }
-
- asm(XEN_EMULATE_PREFIX "cpuid"
- : "=a" (*ax),
- "=b" (*bx),
- "=c" (*cx),
- "=d" (*dx)
- : "0" (*ax), "2" (*cx));
-
- *bx &= maskebx;
- *cx &= maskecx;
- *cx |= setecx;
- *dx &= maskedx;
-}
-STACK_FRAME_NON_STANDARD(xen_cpuid); /* XEN_EMULATE_PREFIX */
-
-static bool __init xen_check_mwait(void)
-{
-#ifdef CONFIG_ACPI
- struct xen_platform_op op = {
- .cmd = XENPF_set_processor_pminfo,
- .u.set_pminfo.id = -1,
- .u.set_pminfo.type = XEN_PM_PDC,
- };
- uint32_t buf[3];
- unsigned int ax, bx, cx, dx;
- unsigned int mwait_mask;
-
- /* We need to determine whether it is OK to expose the MWAIT
- * capability to the kernel to harvest deeper than C3 states from ACPI
- * _CST using the processor_harvest_xen.c module. For this to work, we
- * need to gather the MWAIT_LEAF values (which the cstate.c code
- * checks against). The hypervisor won't expose the MWAIT flag because
- * it would break backwards compatibility; so we will find out directly
- * from the hardware and hypercall.
- */
- if (!xen_initial_domain())
- return false;
-
- /*
- * When running under platform earlier than Xen4.2, do not expose
- * mwait, to avoid the risk of loading native acpi pad driver
- */
- if (!xen_running_on_version_or_later(4, 2))
- return false;
-
- ax = 1;
- cx = 0;
-
- native_cpuid(&ax, &bx, &cx, &dx);
-
- mwait_mask = (1 << (X86_FEATURE_EST % 32)) |
- (1 << (X86_FEATURE_MWAIT % 32));
-
- if ((cx & mwait_mask) != mwait_mask)
- return false;
-
- /* We need to emulate the MWAIT_LEAF and for that we need both
- * ecx and edx. The hypercall provides only partial information.
- */
-
- ax = CPUID_MWAIT_LEAF;
- 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,
- * 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);
-
- 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))) {
- cpuid_leaf5_ecx_val = cx;
- cpuid_leaf5_edx_val = dx;
- }
- return true;
-#else
- return false;
-#endif
-}
-static void __init xen_init_cpuid_mask(void)
-{
- unsigned int ax, bx, cx, dx;
- unsigned int xsave_mask;
-
- cpuid_leaf1_edx_mask =
- ~((1 << X86_FEATURE_MTRR) | /* disable MTRR */
- (1 << X86_FEATURE_ACC)); /* thermal monitoring */
-
- if (!xen_initial_domain())
- cpuid_leaf1_edx_mask &=
- ~((1 << X86_FEATURE_ACPI)); /* disable ACPI */
-
- cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_X2APIC % 32));
-
- ax = 1;
- cx = 0;
- cpuid(1, &ax, &bx, &cx, &dx);
-
- xsave_mask =
- (1 << (X86_FEATURE_XSAVE % 32)) |
- (1 << (X86_FEATURE_OSXSAVE % 32));
-
- /* Xen will set CR4.OSXSAVE if supported and not disabled by force */
- if ((cx & xsave_mask) != xsave_mask)
- cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */
- if (xen_check_mwait())
- cpuid_leaf1_ecx_set_mask = (1 << (X86_FEATURE_MWAIT % 32));
-}
-
-static void xen_set_debugreg(int reg, unsigned long val)
-{
- HYPERVISOR_set_debugreg(reg, val);
-}
-
-static unsigned long xen_get_debugreg(int reg)
-{
- return HYPERVISOR_get_debugreg(reg);
-}
-
-static void xen_end_context_switch(struct task_struct *next)
-{
- xen_mc_flush();
- paravirt_end_context_switch(next);
-}
-
-static unsigned long xen_store_tr(void)
-{
- return 0;
-}
-
-/*
- * Set the page permissions for a particular virtual address. If the
- * address is a vmalloc mapping (or other non-linear mapping), then
- * find the linear mapping of the page and also set its protections to
- * match.
- */
-static void set_aliased_prot(void *v, pgprot_t prot)
-{
- int level;
- pte_t *ptep;
- pte_t pte;
- unsigned long pfn;
- struct page *page;
- unsigned char dummy;
-
- ptep = lookup_address((unsigned long)v, &level);
- BUG_ON(ptep == NULL);
-
- pfn = pte_pfn(*ptep);
- page = pfn_to_page(pfn);
-
- pte = pfn_pte(pfn, prot);
-
- /*
- * Careful: update_va_mapping() will fail if the virtual address
- * we're poking isn't populated in the page tables. We don't
- * need to worry about the direct map (that's always in the page
- * tables), but we need to be careful about vmap space. In
- * particular, the top level page table can lazily propagate
- * entries between processes, so if we've switched mms since we
- * vmapped the target in the first place, we might not have the
- * top-level page table entry populated.
- *
- * We disable preemption because we want the same mm active when
- * we probe the target and when we issue the hypercall. We'll
- * have the same nominal mm, but if we're a kernel thread, lazy
- * mm dropping could change our pgd.
- *
- * Out of an abundance of caution, this uses __get_user() to fault
- * in the target address just in case there's some obscure case
- * in which the target address isn't readable.
- */
-
- preempt_disable();
-
- probe_kernel_read(&dummy, v, 1);
+ for_each_online_cpu(cpu)
+ xen_pmu_finish(cpu);
- if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
+ if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
BUG();
-
- if (!PageHighMem(page)) {
- void *av = __va(PFN_PHYS(pfn));
-
- if (av != v)
- if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
- BUG();
- } else
- kmap_flush_unused();
-
- preempt_enable();
-}
-
-static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
-{
- const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
- int i;
-
- /*
- * We need to mark the all aliases of the LDT pages RO. We
- * don't need to call vm_flush_aliases(), though, since that's
- * only responsible for flushing aliases out the TLBs, not the
- * page tables, and Xen will flush the TLB for us if needed.
- *
- * To avoid confusing future readers: none of this is necessary
- * to load the LDT. The hypervisor only checks this when the
- * LDT is faulted in due to subsequent descriptor access.
- */
-
- for(i = 0; i < entries; i += entries_per_page)
- set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
}
-static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
-{
- const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
- int i;
-
- for(i = 0; i < entries; i += entries_per_page)
- set_aliased_prot(ldt + i, PAGE_KERNEL);
-}
-
-static void xen_set_ldt(const void *addr, unsigned entries)
+void xen_emergency_restart(void)
{
- struct mmuext_op *op;
- struct multicall_space mcs = xen_mc_entry(sizeof(*op));
-
- trace_xen_cpu_set_ldt(addr, entries);
-
- op = mcs.args;
- op->cmd = MMUEXT_SET_LDT;
- op->arg1.linear_addr = (unsigned long)addr;
- op->arg2.nr_ents = entries;
-
- MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
-
- xen_mc_issue(PARAVIRT_LAZY_CPU);
+ xen_reboot(SHUTDOWN_reboot);
}
-static void xen_load_gdt(const struct desc_ptr *dtr)
+static int
+xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
{
- unsigned long va = dtr->address;
- unsigned int size = dtr->size + 1;
- unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
- unsigned long frames[pages];
- int f;
-
- /*
- * A GDT can be up to 64k in size, which corresponds to 8192
- * 8-byte entries, or 16 4k pages..
- */
-
- BUG_ON(size > 65536);
- BUG_ON(va & ~PAGE_MASK);
-
- for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
- int level;
- pte_t *ptep;
- unsigned long pfn, mfn;
- void *virt;
-
- /*
- * The GDT is per-cpu and is in the percpu data area.
- * That can be virtually mapped, so we need to do a
- * page-walk to get the underlying MFN for the
- * hypercall. The page can also be in the kernel's
- * linear range, so we need to RO that mapping too.
- */
- ptep = lookup_address(va, &level);
- BUG_ON(ptep == NULL);
-
- pfn = pte_pfn(*ptep);
- mfn = pfn_to_mfn(pfn);
- virt = __va(PFN_PHYS(pfn));
-
- frames[f] = mfn;
-
- make_lowmem_page_readonly((void *)va);
- make_lowmem_page_readonly(virt);
- }
-
- if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
- BUG();
+ if (!kexec_crash_loaded())
+ xen_reboot(SHUTDOWN_crash);
+ return NOTIFY_DONE;
}
-/*
- * load_gdt for early boot, when the gdt is only mapped once
- */
-static void __init xen_load_gdt_boot(const struct desc_ptr *dtr)
-{
- unsigned long va = dtr->address;
- unsigned int size = dtr->size + 1;
- unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
- unsigned long frames[pages];
- int f;
-
- /*
- * A GDT can be up to 64k in size, which corresponds to 8192
- * 8-byte entries, or 16 4k pages..
- */
-
- BUG_ON(size > 65536);
- BUG_ON(va & ~PAGE_MASK);
-
- for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
- pte_t pte;
- unsigned long pfn, mfn;
-
- pfn = virt_to_pfn(va);
- mfn = pfn_to_mfn(pfn);
-
- pte = pfn_pte(pfn, PAGE_KERNEL_RO);
-
- if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0))
- BUG();
-
- frames[f] = mfn;
- }
-
- if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
- BUG();
-}
+static struct notifier_block xen_panic_block = {
+ .notifier_call = xen_panic_event,
+ .priority = INT_MIN
+};
-static inline bool desc_equal(const struct desc_struct *d1,
- const struct desc_struct *d2)
+int xen_panic_handler_init(void)
{
- return d1->a == d2->a && d1->b == d2->b;
+ atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block);
+ return 0;
}
-static void load_TLS_descriptor(struct thread_struct *t,
- unsigned int cpu, unsigned int i)
+void xen_pin_vcpu(int cpu)
{
- struct desc_struct *shadow = &per_cpu(shadow_tls_desc, cpu).desc[i];
- struct desc_struct *gdt;
- xmaddr_t maddr;
- struct multicall_space mc;
+ static bool disable_pinning;
+ struct sched_pin_override pin_override;
+ int ret;
- if (desc_equal(shadow, &t->tls_array[i]))
+ if (disable_pinning)
return;
- *shadow = t->tls_array[i];
-
- gdt = get_cpu_gdt_rw(cpu);
- maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
- mc = __xen_mc_entry(0);
+ pin_override.pcpu = cpu;
+ ret = HYPERVISOR_sched_op(SCHEDOP_pin_override, &pin_override);
- MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
-}
+ /* Ignore errors when removing override. */
+ if (cpu < 0)
+ return;
-static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
-{
- /*
- * XXX sleazy hack: If we're being called in a lazy-cpu zone
- * and lazy gs handling is enabled, it means we're in a
- * context switch, and %gs has just been saved. This means we
- * can zero it out to prevent faults on exit from the
- * hypervisor if the next process has no %gs. Either way, it
- * has been saved, and the new value will get loaded properly.
- * This will go away as soon as Xen has been modified to not
- * save/restore %gs for normal hypercalls.
- *
- * On x86_64, this hack is not used for %gs, because gs points
- * to KERNEL_GS_BASE (and uses it for PDA references), so we
- * must not zero %gs on x86_64
- *
- * For x86_64, we need to zero %fs, otherwise we may get an
- * exception between the new %fs descriptor being loaded and
- * %fs being effectively cleared at __switch_to().
- */
- if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
-#ifdef CONFIG_X86_32
- lazy_load_gs(0);
-#else
- loadsegment(fs, 0);
-#endif
+ switch (ret) {
+ case -ENOSYS:
+ pr_warn("Unable to pin on physical cpu %d. In case of problems consider vcpu pinning.\n",
+ cpu);
+ disable_pinning = true;
+ break;
+ case -EPERM:
+ WARN(1, "Trying to pin vcpu without having privilege to do so\n");
+ disable_pinning = true;
+ break;
+ case -EINVAL:
+ case -EBUSY:
+ pr_warn("Physical cpu %d not available for pinning. Check Xen cpu configuration.\n",
+ cpu);
+ break;
+ case 0:
+ break;
+ default:
+ WARN(1, "rc %d while trying to pin vcpu\n", ret);
+ disable_pinning = true;
}
-
- xen_mc_batch();
-
- load_TLS_descriptor(t, cpu, 0);
- load_TLS_descriptor(t, cpu, 1);
- load_TLS_descriptor(t, cpu, 2);
-
- xen_mc_issue(PARAVIRT_LAZY_CPU);
-}
-
-#ifdef CONFIG_X86_64
-static void xen_load_gs_index(unsigned int idx)
-{
- if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
- BUG();
-}
-#endif
-
-static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
- const void *ptr)
-{
- xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]);
- u64 entry = *(u64 *)ptr;
-
- trace_xen_cpu_write_ldt_entry(dt, entrynum, entry);
-
- preempt_disable();
-
- xen_mc_flush();
- if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
- BUG();
-
- preempt_enable();
}
-static int cvt_gate_to_trap(int vector, const gate_desc *val,
- struct trap_info *info)
-{
- unsigned long addr;
-
- if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
- return 0;
-
- info->vector = vector;
-
- addr = gate_offset(*val);
-#ifdef CONFIG_X86_64
- /*
- * Look for known traps using IST, and substitute them
- * appropriately. The debugger ones are the only ones we care
- * about. Xen will handle faults like double_fault,
- * so we should never see them. Warn if
- * there's an unexpected IST-using fault handler.
- */
- if (addr == (unsigned long)debug)
- addr = (unsigned long)xen_debug;
- else if (addr == (unsigned long)int3)
- addr = (unsigned long)xen_int3;
- else if (addr == (unsigned long)stack_segment)
- addr = (unsigned long)xen_stack_segment;
- else if (addr == (unsigned long)double_fault) {
- /* Don't need to handle these */
- return 0;
-#ifdef CONFIG_X86_MCE
- } else if (addr == (unsigned long)machine_check) {
- /*
- * when xen hypervisor inject vMCE to guest,
- * use native mce handler to handle it
- */
- ;
-#endif
- } else if (addr == (unsigned long)nmi)
- /*
- * Use the native version as well.
- */
- ;
- else {
- /* Some other trap using IST? */
- if (WARN_ON(val->ist != 0))
- return 0;
- }
-#endif /* CONFIG_X86_64 */
- info->address = addr;
-
- info->cs = gate_segment(*val);
- info->flags = val->dpl;
- /* interrupt gates clear IF */
- if (val->type == GATE_INTERRUPT)
- info->flags |= 1 << 2;
-
- return 1;
-}
-
-/* Locations of each CPU's IDT */
-static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
-
-/* Set an IDT entry. If the entry is part of the current IDT, then
- also update Xen. */
-static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
-{
- unsigned long p = (unsigned long)&dt[entrynum];
- unsigned long start, end;
-
- trace_xen_cpu_write_idt_entry(dt, entrynum, g);
-
- preempt_disable();
-
- start = __this_cpu_read(idt_desc.address);
- end = start + __this_cpu_read(idt_desc.size) + 1;
-
- xen_mc_flush();
-
- native_write_idt_entry(dt, entrynum, g);
-
- if (p >= start && (p + 8) <= end) {
- struct trap_info info[2];
-
- info[1].address = 0;
-
- if (cvt_gate_to_trap(entrynum, g, &info[0]))
- if (HYPERVISOR_set_trap_table(info))
- BUG();
- }
-
- preempt_enable();
-}
-
-static void xen_convert_trap_info(const struct desc_ptr *desc,
- struct trap_info *traps)
-{
- unsigned in, out, count;
-
- count = (desc->size+1) / sizeof(gate_desc);
- BUG_ON(count > 256);
-
- for (in = out = 0; in < count; in++) {
- gate_desc *entry = (gate_desc*)(desc->address) + in;
-
- if (cvt_gate_to_trap(in, entry, &traps[out]))
- out++;
- }
- traps[out].address = 0;
-}
-
-void xen_copy_trap_info(struct trap_info *traps)
-{
- const struct desc_ptr *desc = this_cpu_ptr(&idt_desc);
-
- xen_convert_trap_info(desc, traps);
-}
-
-/* Load a new IDT into Xen. In principle this can be per-CPU, so we
- hold a spinlock to protect the static traps[] array (static because
- it avoids allocation, and saves stack space). */
-static void xen_load_idt(const struct desc_ptr *desc)
-{
- static DEFINE_SPINLOCK(lock);
- static struct trap_info traps[257];
-
- trace_xen_cpu_load_idt(desc);
-
- spin_lock(&lock);
-
- memcpy(this_cpu_ptr(&idt_desc), desc, sizeof(idt_desc));
-
- xen_convert_trap_info(desc, traps);
-
- xen_mc_flush();
- if (HYPERVISOR_set_trap_table(traps))
- BUG();
-
- spin_unlock(&lock);
-}
-
-/* Write a GDT descriptor entry. Ignore LDT descriptors, since
- they're handled differently. */
-static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
- const void *desc, int type)
-{
- trace_xen_cpu_write_gdt_entry(dt, entry, desc, type);
-
- preempt_disable();
-
- switch (type) {
- case DESC_LDT:
- case DESC_TSS:
- /* ignore */
- break;
-
- default: {
- xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]);
-
- xen_mc_flush();
- if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
- BUG();
- }
-
- }
-
- preempt_enable();
-}
-
-/*
- * Version of write_gdt_entry for use at early boot-time needed to
- * update an entry as simply as possible.
- */
-static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry,
- const void *desc, int type)
-{
- trace_xen_cpu_write_gdt_entry(dt, entry, desc, type);
-
- switch (type) {
- case DESC_LDT:
- case DESC_TSS:
- /* ignore */
- break;
-
- default: {
- xmaddr_t maddr = virt_to_machine(&dt[entry]);
-
- if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
- dt[entry] = *(struct desc_struct *)desc;
- }
-
- }
-}
-
-static void xen_load_sp0(struct tss_struct *tss,
- struct thread_struct *thread)
-{
- struct multicall_space mcs;
-
- mcs = xen_mc_entry(0);
- MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
- xen_mc_issue(PARAVIRT_LAZY_CPU);
- tss->x86_tss.sp0 = thread->sp0;
-}
-
-void xen_set_iopl_mask(unsigned mask)
-{
- struct physdev_set_iopl set_iopl;
-
- /* Force the change at ring 0. */
- set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
- HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
-}
-
-static void xen_io_delay(void)
-{
-}
-
-static DEFINE_PER_CPU(unsigned long, xen_cr0_value);
-
-static unsigned long xen_read_cr0(void)
-{
- unsigned long cr0 = this_cpu_read(xen_cr0_value);
-
- if (unlikely(cr0 == 0)) {
- cr0 = native_read_cr0();
- this_cpu_write(xen_cr0_value, cr0);
- }
-
- return cr0;
-}
-
-static void xen_write_cr0(unsigned long cr0)
-{
- struct multicall_space mcs;
-
- this_cpu_write(xen_cr0_value, cr0);
-
- /* Only pay attention to cr0.TS; everything else is
- ignored. */
- mcs = xen_mc_entry(0);
-
- MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
-
- xen_mc_issue(PARAVIRT_LAZY_CPU);
-}
-
-static void xen_write_cr4(unsigned long cr4)
-{
- cr4 &= ~(X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PCE);
-
- native_write_cr4(cr4);
-}
-#ifdef CONFIG_X86_64
-static inline unsigned long xen_read_cr8(void)
-{
- return 0;
-}
-static inline void xen_write_cr8(unsigned long val)
-{
- BUG_ON(val);
-}
-#endif
-
-static u64 xen_read_msr_safe(unsigned int msr, int *err)
-{
- u64 val;
-
- if (pmu_msr_read(msr, &val, err))
- return val;
-
- val = native_read_msr_safe(msr, err);
- switch (msr) {
- case MSR_IA32_APICBASE:
-#ifdef CONFIG_X86_X2APIC
- if (!(cpuid_ecx(1) & (1 << (X86_FEATURE_X2APIC & 31))))
-#endif
- val &= ~X2APIC_ENABLE;
- break;
- }
- return val;
-}
-
-static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
-{
- int ret;
-
- ret = 0;
-
- switch (msr) {
-#ifdef CONFIG_X86_64
- unsigned which;
- u64 base;
-
- case MSR_FS_BASE: which = SEGBASE_FS; goto set;
- case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set;
- case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set;
-
- set:
- base = ((u64)high << 32) | low;
- if (HYPERVISOR_set_segment_base(which, base) != 0)
- ret = -EIO;
- break;
-#endif
-
- case MSR_STAR:
- case MSR_CSTAR:
- case MSR_LSTAR:
- case MSR_SYSCALL_MASK:
- case MSR_IA32_SYSENTER_CS:
- case MSR_IA32_SYSENTER_ESP:
- case MSR_IA32_SYSENTER_EIP:
- /* Fast syscall setup is all done in hypercalls, so
- these are all ignored. Stub them out here to stop
- Xen console noise. */
- break;
-
- default:
- if (!pmu_msr_write(msr, low, high, &ret))
- ret = native_write_msr_safe(msr, low, high);
- }
-
- return ret;
-}
-
-static u64 xen_read_msr(unsigned int msr)
-{
- /*
- * This will silently swallow a #GP from RDMSR. It may be worth
- * changing that.
- */
- int err;
-
- return xen_read_msr_safe(msr, &err);
-}
-
-static void xen_write_msr(unsigned int msr, unsigned low, unsigned high)
-{
- /*
- * This will silently swallow a #GP from WRMSR. It may be worth
- * changing that.
- */
- xen_write_msr_safe(msr, low, high);
-}
-
-void xen_setup_shared_info(void)
-{
- if (!xen_feature(XENFEAT_auto_translated_physmap)) {
- set_fixmap(FIX_PARAVIRT_BOOTMAP,
- xen_start_info->shared_info);
-
- HYPERVISOR_shared_info =
- (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
- } else
- HYPERVISOR_shared_info =
- (struct shared_info *)__va(xen_start_info->shared_info);
-
-#ifndef CONFIG_SMP
- /* In UP this is as good a place as any to set up shared info */
- xen_setup_vcpu_info_placement();
-#endif
-
- xen_setup_mfn_list_list();
-}
-
-/* This is called once we have the cpu_possible_mask */
-void xen_setup_vcpu_info_placement(void)
-{
- int cpu;
-
- for_each_possible_cpu(cpu) {
- /* Set up direct vCPU id mapping for PV guests. */
- per_cpu(xen_vcpu_id, cpu) = cpu;
- xen_vcpu_setup(cpu);
- }
-
- /*
- * xen_vcpu_setup managed to place the vcpu_info within the
- * percpu area for all cpus, so make use of it.
- */
- if (xen_have_vcpu_info_placement) {
- pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
- pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
- pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
- pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
- pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
- }
-}
-
-static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
- unsigned long addr, unsigned len)
-{
- char *start, *end, *reloc;
- unsigned ret;
-
- start = end = reloc = NULL;
-
-#define SITE(op, x) \
- case PARAVIRT_PATCH(op.x): \
- if (xen_have_vcpu_info_placement) { \
- start = (char *)xen_##x##_direct; \
- end = xen_##x##_direct_end; \
- reloc = xen_##x##_direct_reloc; \
- } \
- goto patch_site
-
- switch (type) {
- SITE(pv_irq_ops, irq_enable);
- SITE(pv_irq_ops, irq_disable);
- SITE(pv_irq_ops, save_fl);
- SITE(pv_irq_ops, restore_fl);
-#undef SITE
-
- patch_site:
- if (start == NULL || (end-start) > len)
- goto default_patch;
-
- ret = paravirt_patch_insns(insnbuf, len, start, end);
-
- /* Note: because reloc is assigned from something that
- appears to be an array, gcc assumes it's non-null,
- but doesn't know its relationship with start and
- end. */
- if (reloc > start && reloc < end) {
- int reloc_off = reloc - start;
- long *relocp = (long *)(insnbuf + reloc_off);
- long delta = start - (char *)addr;
-
- *relocp += delta;
- }
- break;
-
- default_patch:
- default:
- ret = paravirt_patch_default(type, clobbers, insnbuf,
- addr, len);
- break;
- }
-
- return ret;
-}
-
-static const struct pv_info xen_info __initconst = {
- .shared_kernel_pmd = 0,
-
-#ifdef CONFIG_X86_64
- .extra_user_64bit_cs = FLAT_USER_CS64,
-#endif
- .name = "Xen",
-};
-
-static const struct pv_init_ops xen_init_ops __initconst = {
- .patch = xen_patch,
-};
-
-static const struct pv_cpu_ops xen_cpu_ops __initconst = {
- .cpuid = xen_cpuid,
-
- .set_debugreg = xen_set_debugreg,
- .get_debugreg = xen_get_debugreg,
-
- .read_cr0 = xen_read_cr0,
- .write_cr0 = xen_write_cr0,
-
- .read_cr4 = native_read_cr4,
- .write_cr4 = xen_write_cr4,
-
-#ifdef CONFIG_X86_64
- .read_cr8 = xen_read_cr8,
- .write_cr8 = xen_write_cr8,
-#endif
-
- .wbinvd = native_wbinvd,
-
- .read_msr = xen_read_msr,
- .write_msr = xen_write_msr,
-
- .read_msr_safe = xen_read_msr_safe,
- .write_msr_safe = xen_write_msr_safe,
-
- .read_pmc = xen_read_pmc,
-
- .iret = xen_iret,
-#ifdef CONFIG_X86_64
- .usergs_sysret64 = xen_sysret64,
-#endif
-
- .load_tr_desc = paravirt_nop,
- .set_ldt = xen_set_ldt,
- .load_gdt = xen_load_gdt,
- .load_idt = xen_load_idt,
- .load_tls = xen_load_tls,
-#ifdef CONFIG_X86_64
- .load_gs_index = xen_load_gs_index,
-#endif
-
- .alloc_ldt = xen_alloc_ldt,
- .free_ldt = xen_free_ldt,
-
- .store_idt = native_store_idt,
- .store_tr = xen_store_tr,
-
- .write_ldt_entry = xen_write_ldt_entry,
- .write_gdt_entry = xen_write_gdt_entry,
- .write_idt_entry = xen_write_idt_entry,
- .load_sp0 = xen_load_sp0,
-
- .set_iopl_mask = xen_set_iopl_mask,
- .io_delay = xen_io_delay,
-
- /* Xen takes care of %gs when switching to usermode for us */
- .swapgs = paravirt_nop,
-
- .start_context_switch = paravirt_start_context_switch,
- .end_context_switch = xen_end_context_switch,
-};
-
-void xen_reboot(int reason)
-{
- struct sched_shutdown r = { .reason = reason };
- int cpu;
-
- for_each_online_cpu(cpu)
- xen_pmu_finish(cpu);
-
- if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
- BUG();
-}
-
-static void xen_restart(char *msg)
-{
- xen_reboot(SHUTDOWN_reboot);
-}
-
-void xen_emergency_restart(void)
-{
- xen_reboot(SHUTDOWN_reboot);
-}
-
-static void xen_machine_halt(void)
-{
- xen_reboot(SHUTDOWN_poweroff);
-}
-
-static void xen_machine_power_off(void)
-{
- if (pm_power_off)
- pm_power_off();
- xen_reboot(SHUTDOWN_poweroff);
-}
-
-static void xen_crash_shutdown(struct pt_regs *regs)
-{
- xen_reboot(SHUTDOWN_crash);
-}
-
-static int
-xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
-{
- if (!kexec_crash_loaded())
- xen_reboot(SHUTDOWN_crash);
- return NOTIFY_DONE;
-}
-
-static struct notifier_block xen_panic_block = {
- .notifier_call= xen_panic_event,
- .priority = INT_MIN
-};
-
-int xen_panic_handler_init(void)
-{
- atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block);
- return 0;
-}
-
-static const struct machine_ops xen_machine_ops __initconst = {
- .restart = xen_restart,
- .halt = xen_machine_halt,
- .power_off = xen_machine_power_off,
- .shutdown = xen_machine_halt,
- .crash_shutdown = xen_crash_shutdown,
- .emergency_restart = xen_emergency_restart,
-};
-
-static unsigned char xen_get_nmi_reason(void)
-{
- unsigned char reason = 0;
-
- /* Construct a value which looks like it came from port 0x61. */
- if (test_bit(_XEN_NMIREASON_io_error,
- &HYPERVISOR_shared_info->arch.nmi_reason))
- reason |= NMI_REASON_IOCHK;
- if (test_bit(_XEN_NMIREASON_pci_serr,
- &HYPERVISOR_shared_info->arch.nmi_reason))
- reason |= NMI_REASON_SERR;
-
- return reason;
-}
-
-static void __init xen_boot_params_init_edd(void)
-{
-#if IS_ENABLED(CONFIG_EDD)
- struct xen_platform_op op;
- struct edd_info *edd_info;
- u32 *mbr_signature;
- unsigned nr;
- int ret;
-
- edd_info = boot_params.eddbuf;
- mbr_signature = boot_params.edd_mbr_sig_buffer;
-
- op.cmd = XENPF_firmware_info;
-
- op.u.firmware_info.type = XEN_FW_DISK_INFO;
- for (nr = 0; nr < EDDMAXNR; nr++) {
- struct edd_info *info = edd_info + nr;
-
- op.u.firmware_info.index = nr;
- info->params.length = sizeof(info->params);
- set_xen_guest_handle(op.u.firmware_info.u.disk_info.edd_params,
- &info->params);
- ret = HYPERVISOR_platform_op(&op);
- if (ret)
- break;
-
-#define C(x) info->x = op.u.firmware_info.u.disk_info.x
- C(device);
- C(version);
- C(interface_support);
- C(legacy_max_cylinder);
- C(legacy_max_head);
- C(legacy_sectors_per_track);
-#undef C
- }
- boot_params.eddbuf_entries = nr;
-
- op.u.firmware_info.type = XEN_FW_DISK_MBR_SIGNATURE;
- for (nr = 0; nr < EDD_MBR_SIG_MAX; nr++) {
- op.u.firmware_info.index = nr;
- ret = HYPERVISOR_platform_op(&op);
- if (ret)
- break;
- mbr_signature[nr] = op.u.firmware_info.u.disk_mbr_signature.mbr_signature;
- }
- boot_params.edd_mbr_sig_buf_entries = nr;
-#endif
-}
-
-/*
- * Set up the GDT and segment registers for -fstack-protector. Until
- * we do this, we have to be careful not to call any stack-protected
- * function, which is most of the kernel.
- */
-static void xen_setup_gdt(int cpu)
-{
- pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot;
- pv_cpu_ops.load_gdt = xen_load_gdt_boot;
-
- setup_stack_canary_segment(0);
- switch_to_new_gdt(0);
-
- pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry;
- pv_cpu_ops.load_gdt = xen_load_gdt;
-}
-
-static void __init xen_dom0_set_legacy_features(void)
-{
- x86_platform.legacy.rtc = 1;
-}
-
-int xen_cpuhp_setup(int (*cpu_up_prepare_cb)(unsigned int),
- int (*cpu_dead_cb)(unsigned int))
-{
- int rc;
-
- rc = cpuhp_setup_state_nocalls(CPUHP_XEN_PREPARE,
- "x86/xen/hvm_guest:prepare",
- cpu_up_prepare_cb, cpu_dead_cb);
- if (rc >= 0) {
- rc = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
- "x86/xen/hvm_guest:online",
- xen_cpu_up_online, NULL);
- if (rc < 0)
- cpuhp_remove_state_nocalls(CPUHP_XEN_PREPARE);
- }
-
- return rc >= 0 ? 0 : rc;
-}
-
-/* First C function to be called on Xen boot */
-asmlinkage __visible void __init xen_start_kernel(void)
-{
- struct physdev_set_iopl set_iopl;
- unsigned long initrd_start = 0;
- int rc;
-
- if (!xen_start_info)
- return;
-
- xen_domain_type = XEN_PV_DOMAIN;
-
- xen_setup_features();
-
- xen_setup_machphys_mapping();
-
- /* Install Xen paravirt ops */
- pv_info = xen_info;
- pv_init_ops = xen_init_ops;
- pv_cpu_ops = xen_cpu_ops;
-
- x86_platform.get_nmi_reason = xen_get_nmi_reason;
-
- x86_init.resources.memory_setup = xen_memory_setup;
- x86_init.oem.arch_setup = xen_arch_setup;
- x86_init.oem.banner = xen_banner;
-
- xen_init_time_ops();
-
- /*
- * Set up some pagetable state before starting to set any ptes.
- */
-
- xen_init_mmu_ops();
-
- /* Prevent unwanted bits from being set in PTEs. */
- __supported_pte_mask &= ~_PAGE_GLOBAL;
-
- /*
- * Prevent page tables from being allocated in highmem, even
- * if CONFIG_HIGHPTE is enabled.
- */
- __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
-
- /* Work out if we support NX */
- x86_configure_nx();
-
- /* Get mfn list */
- xen_build_dynamic_phys_to_machine();
-
- /*
- * Set up kernel GDT and segment registers, mainly so that
- * -fstack-protector code can be executed.
- */
- xen_setup_gdt(0);
-
- xen_init_irq_ops();
- xen_init_cpuid_mask();
-
-#ifdef CONFIG_X86_LOCAL_APIC
- /*
- * set up the basic apic ops.
- */
- xen_init_apic();
-#endif
-
- if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
- pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
- pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
- }
-
- machine_ops = xen_machine_ops;
-
- /*
- * The only reliable way to retain the initial address of the
- * percpu gdt_page is to remember it here, so we can go and
- * mark it RW later, when the initial percpu area is freed.
- */
- xen_initial_gdt = &per_cpu(gdt_page, 0);
-
- xen_smp_init();
-
-#ifdef CONFIG_ACPI_NUMA
- /*
- * The pages we from Xen are not related to machine pages, so
- * any NUMA information the kernel tries to get from ACPI will
- * be meaningless. Prevent it from trying.
- */
- acpi_numa = -1;
-#endif
- /* Don't do the full vcpu_info placement stuff until we have a
- possible map and a non-dummy shared_info. */
- per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
-
- 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,
- xen_start_info->nr_pages);
- xen_reserve_special_pages();
-
- /* keep using Xen gdt for now; no urgent need to change it */
-
-#ifdef CONFIG_X86_32
- pv_info.kernel_rpl = 1;
- if (xen_feature(XENFEAT_supervisor_mode_kernel))
- pv_info.kernel_rpl = 0;
-#else
- pv_info.kernel_rpl = 0;
-#endif
- /* set the limit of our address space */
- xen_reserve_top();
-
- /*
- * We used to do this in xen_arch_setup, but that is too late
- * on AMD were early_cpu_init (run before ->arch_setup()) calls
- * early_amd_init which pokes 0xcf8 port.
- */
- set_iopl.iopl = 1;
- rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
- if (rc != 0)
- xen_raw_printk("physdev_op failed %d\n", rc);
-
-#ifdef CONFIG_X86_32
- /* set up basic CPUID stuff */
- cpu_detect(&new_cpu_data);
- set_cpu_cap(&new_cpu_data, X86_FEATURE_FPU);
- new_cpu_data.x86_capability[CPUID_1_EDX] = cpuid_edx(1);
-#endif
-
- if (xen_start_info->mod_start) {
- if (xen_start_info->flags & SIF_MOD_START_PFN)
- initrd_start = PFN_PHYS(xen_start_info->mod_start);
- else
- initrd_start = __pa(xen_start_info->mod_start);
- }
-
- /* Poke various useful things into boot_params */
- boot_params.hdr.type_of_loader = (9 << 4) | 0;
- boot_params.hdr.ramdisk_image = initrd_start;
- boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
- boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
- boot_params.hdr.hardware_subarch = X86_SUBARCH_XEN;
-
- if (!xen_initial_domain()) {
- add_preferred_console("xenboot", 0, NULL);
- add_preferred_console("tty", 0, NULL);
- add_preferred_console("hvc", 0, NULL);
- if (pci_xen)
- x86_init.pci.arch_init = pci_xen_init;
- } else {
- const struct dom0_vga_console_info *info =
- (void *)((char *)xen_start_info +
- xen_start_info->console.dom0.info_off);
- struct xen_platform_op op = {
- .cmd = XENPF_firmware_info,
- .interface_version = XENPF_INTERFACE_VERSION,
- .u.firmware_info.type = XEN_FW_KBD_SHIFT_FLAGS,
- };
-
- x86_platform.set_legacy_features =
- xen_dom0_set_legacy_features;
- xen_init_vga(info, xen_start_info->console.dom0.info_size);
- xen_start_info->console.domU.mfn = 0;
- xen_start_info->console.domU.evtchn = 0;
-
- if (HYPERVISOR_platform_op(&op) == 0)
- boot_params.kbd_status = op.u.firmware_info.u.kbd_shift_flags;
-
- /* Make sure ACS will be enabled */
- pci_request_acs();
-
- xen_acpi_sleep_register();
-
- /* Avoid searching for BIOS MP tables */
- x86_init.mpparse.find_smp_config = x86_init_noop;
- x86_init.mpparse.get_smp_config = x86_init_uint_noop;
-
- xen_boot_params_init_edd();
- }
-#ifdef CONFIG_PCI
- /* PCI BIOS service won't work from a PV guest. */
- pci_probe &= ~PCI_PROBE_BIOS;
-#endif
- xen_raw_console_write("about to get started...\n");
-
- /* Let's presume PV guests always boot on vCPU with id 0. */
- per_cpu(xen_vcpu_id, 0) = 0;
-
- xen_setup_runstate_info(0);
-
- xen_efi_init();
-
- /* Start the world */
-#ifdef CONFIG_X86_32
- i386_start_kernel();
-#else
- cr4_init_shadow(); /* 32b kernel does this in i386_start_kernel() */
- x86_64_start_reservations((char *)__pa_symbol(&boot_params));
-#endif
-}
-
-static int xen_cpu_up_prepare_pv(unsigned int cpu)
-{
- int rc;
-
- xen_setup_timer(cpu);
-
- rc = xen_smp_intr_init(cpu);
- if (rc) {
- WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n",
- cpu, rc);
- return rc;
- }
- return 0;
-}
-
-static int xen_cpu_dead_pv(unsigned int cpu)
-{
- xen_smp_intr_free(cpu);
-
- xen_teardown_timer(cpu);
-
- return 0;
-}
-
-static int xen_cpu_up_online(unsigned int cpu)
-{
- xen_init_lock_cpu(cpu);
- return 0;
-}
-
-static uint32_t __init xen_platform_pv(void)
-{
- if (xen_pv_domain())
- return xen_cpuid_base();
-
- return 0;
-}
-
-static void xen_set_cpu_features(struct cpuinfo_x86 *c)
-{
- clear_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
- set_cpu_cap(c, X86_FEATURE_XENPV);
-}
-
-void xen_pin_vcpu(int cpu)
-{
- static bool disable_pinning;
- struct sched_pin_override pin_override;
- int ret;
-
- if (disable_pinning)
- return;
-
- pin_override.pcpu = cpu;
- ret = HYPERVISOR_sched_op(SCHEDOP_pin_override, &pin_override);
-
- /* Ignore errors when removing override. */
- if (cpu < 0)
- return;
-
- switch (ret) {
- case -ENOSYS:
- pr_warn("Unable to pin on physical cpu %d. In case of problems consider vcpu pinning.\n",
- cpu);
- disable_pinning = true;
- break;
- case -EPERM:
- WARN(1, "Trying to pin vcpu without having privilege to do so\n");
- disable_pinning = true;
- break;
- case -EINVAL:
- case -EBUSY:
- pr_warn("Physical cpu %d not available for pinning. Check Xen cpu configuration.\n",
- cpu);
- break;
- case 0:
- break;
- default:
- WARN(1, "rc %d while trying to pin vcpu\n", ret);
- disable_pinning = true;
- }
-}
-
-const struct hypervisor_x86 x86_hyper_xen_pv = {
- .name = "Xen PV",
- .detect = xen_platform_pv,
- .set_cpu_features = xen_set_cpu_features,
- .pin_vcpu = xen_pin_vcpu,
-};
-EXPORT_SYMBOL(x86_hyper_xen_pv);
-
#ifdef CONFIG_HOTPLUG_CPU
void xen_arch_register_cpu(int num)
{
--- /dev/null
+/*
+ * Core of Xen paravirt_ops implementation.
+ *
+ * This file contains the xen_paravirt_ops structure itself, and the
+ * implementations for:
+ * - privileged instructions
+ * - interrupt flags
+ * - segment operations
+ * - booting and setup
+ *
+ * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
+ */
+
+#include <linux/cpu.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/preempt.h>
+#include <linux/hardirq.h>
+#include <linux/percpu.h>
+#include <linux/delay.h>
+#include <linux/start_kernel.h>
+#include <linux/sched.h>
+#include <linux/kprobes.h>
+#include <linux/bootmem.h>
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/page-flags.h>
+#include <linux/highmem.h>
+#include <linux/console.h>
+#include <linux/pci.h>
+#include <linux/gfp.h>
+#include <linux/memblock.h>
+#include <linux/edd.h>
+#include <linux/frame.h>
+
+#include <xen/xen.h>
+#include <xen/events.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/version.h>
+#include <xen/interface/physdev.h>
+#include <xen/interface/vcpu.h>
+#include <xen/interface/memory.h>
+#include <xen/interface/nmi.h>
+#include <xen/interface/xen-mca.h>
+#include <xen/features.h>
+#include <xen/page.h>
+#include <xen/hvc-console.h>
+#include <xen/acpi.h>
+
+#include <asm/paravirt.h>
+#include <asm/apic.h>
+#include <asm/page.h>
+#include <asm/xen/pci.h>
+#include <asm/xen/hypercall.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/cpuid.h>
+#include <asm/fixmap.h>
+#include <asm/processor.h>
+#include <asm/proto.h>
+#include <asm/msr-index.h>
+#include <asm/traps.h>
+#include <asm/setup.h>
+#include <asm/desc.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+#include <asm/reboot.h>
+#include <asm/stackprotector.h>
+#include <asm/hypervisor.h>
+#include <asm/mach_traps.h>
+#include <asm/mwait.h>
+#include <asm/pci_x86.h>
+#include <asm/cpu.h>
+
+#ifdef CONFIG_ACPI
+#include <linux/acpi.h>
+#include <asm/acpi.h>
+#include <acpi/pdc_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"
+
+void *xen_initial_gdt;
+
+RESERVE_BRK(shared_info_page_brk, PAGE_SIZE);
+
+static int xen_cpu_up_prepare_pv(unsigned int cpu);
+static int xen_cpu_dead_pv(unsigned int cpu);
+
+struct tls_descs {
+ struct desc_struct desc[3];
+};
+
+/*
+ * Updating the 3 TLS descriptors in the GDT on every task switch is
+ * surprisingly expensive so we avoid updating them if they haven't
+ * changed. Since Xen writes different descriptors than the one
+ * passed in the update_descriptor hypercall we keep shadow copies to
+ * compare against.
+ */
+static DEFINE_PER_CPU(struct tls_descs, shadow_tls_desc);
+
+/*
+ * On restore, set the vcpu placement up again.
+ * If it fails, then we're in a bad state, since
+ * we can't back out from using it...
+ */
+void xen_vcpu_restore(void)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ bool other_cpu = (cpu != smp_processor_id());
+ bool is_up = HYPERVISOR_vcpu_op(VCPUOP_is_up, xen_vcpu_nr(cpu),
+ NULL);
+
+ if (other_cpu && is_up &&
+ HYPERVISOR_vcpu_op(VCPUOP_down, xen_vcpu_nr(cpu), NULL))
+ BUG();
+
+ xen_setup_runstate_info(cpu);
+
+ if (xen_have_vcpu_info_placement)
+ xen_vcpu_setup(cpu);
+
+ if (other_cpu && is_up &&
+ HYPERVISOR_vcpu_op(VCPUOP_up, xen_vcpu_nr(cpu), NULL))
+ BUG();
+ }
+}
+
+static void __init xen_banner(void)
+{
+ unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL);
+ struct xen_extraversion extra;
+ HYPERVISOR_xen_version(XENVER_extraversion, &extra);
+
+ pr_info("Booting paravirtualized kernel %son %s\n",
+ xen_feature(XENFEAT_auto_translated_physmap) ?
+ "with PVH extensions " : "", pv_info.name);
+ printk(KERN_INFO "Xen version: %d.%d%s%s\n",
+ version >> 16, version & 0xffff, extra.extraversion,
+ xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : "");
+}
+/* Check if running on Xen version (major, minor) or later */
+bool
+xen_running_on_version_or_later(unsigned int major, unsigned int minor)
+{
+ unsigned int version;
+
+ if (!xen_domain())
+ return false;
+
+ version = HYPERVISOR_xen_version(XENVER_version, NULL);
+ if ((((version >> 16) == major) && ((version & 0xffff) >= minor)) ||
+ ((version >> 16) > major))
+ return true;
+ return false;
+}
+
+#define CPUID_THERM_POWER_LEAF 6
+#define APERFMPERF_PRESENT 0
+
+static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
+static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
+
+static __read_mostly unsigned int cpuid_leaf1_ecx_set_mask;
+static __read_mostly unsigned int cpuid_leaf5_ecx_val;
+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 maskecx = ~0;
+ unsigned maskedx = ~0;
+ unsigned setecx = 0;
+ /*
+ * Mask out inconvenient features, to try and disable as many
+ * unsupported kernel subsystems as possible.
+ */
+ switch (*ax) {
+ case 1:
+ maskecx = cpuid_leaf1_ecx_mask;
+ setecx = cpuid_leaf1_ecx_set_mask;
+ maskedx = cpuid_leaf1_edx_mask;
+ break;
+
+ case CPUID_MWAIT_LEAF:
+ /* Synthesize the values.. */
+ *ax = 0;
+ *bx = 0;
+ *cx = cpuid_leaf5_ecx_val;
+ *dx = cpuid_leaf5_edx_val;
+ return;
+
+ case CPUID_THERM_POWER_LEAF:
+ /* Disabling APERFMPERF for kernel usage */
+ maskecx = ~(1 << APERFMPERF_PRESENT);
+ break;
+
+ case 0xb:
+ /* Suppress extended topology stuff */
+ maskebx = 0;
+ break;
+ }
+
+ asm(XEN_EMULATE_PREFIX "cpuid"
+ : "=a" (*ax),
+ "=b" (*bx),
+ "=c" (*cx),
+ "=d" (*dx)
+ : "0" (*ax), "2" (*cx));
+
+ *bx &= maskebx;
+ *cx &= maskecx;
+ *cx |= setecx;
+ *dx &= maskedx;
+}
+STACK_FRAME_NON_STANDARD(xen_cpuid); /* XEN_EMULATE_PREFIX */
+
+static bool __init xen_check_mwait(void)
+{
+#ifdef CONFIG_ACPI
+ struct xen_platform_op op = {
+ .cmd = XENPF_set_processor_pminfo,
+ .u.set_pminfo.id = -1,
+ .u.set_pminfo.type = XEN_PM_PDC,
+ };
+ uint32_t buf[3];
+ unsigned int ax, bx, cx, dx;
+ unsigned int mwait_mask;
+
+ /* We need to determine whether it is OK to expose the MWAIT
+ * capability to the kernel to harvest deeper than C3 states from ACPI
+ * _CST using the processor_harvest_xen.c module. For this to work, we
+ * need to gather the MWAIT_LEAF values (which the cstate.c code
+ * checks against). The hypervisor won't expose the MWAIT flag because
+ * it would break backwards compatibility; so we will find out directly
+ * from the hardware and hypercall.
+ */
+ if (!xen_initial_domain())
+ return false;
+
+ /*
+ * When running under platform earlier than Xen4.2, do not expose
+ * mwait, to avoid the risk of loading native acpi pad driver
+ */
+ if (!xen_running_on_version_or_later(4, 2))
+ return false;
+
+ ax = 1;
+ cx = 0;
+
+ native_cpuid(&ax, &bx, &cx, &dx);
+
+ mwait_mask = (1 << (X86_FEATURE_EST % 32)) |
+ (1 << (X86_FEATURE_MWAIT % 32));
+
+ if ((cx & mwait_mask) != mwait_mask)
+ return false;
+
+ /* We need to emulate the MWAIT_LEAF and for that we need both
+ * ecx and edx. The hypercall provides only partial information.
+ */
+
+ ax = CPUID_MWAIT_LEAF;
+ 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,
+ * 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);
+
+ 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))) {
+ cpuid_leaf5_ecx_val = cx;
+ cpuid_leaf5_edx_val = dx;
+ }
+ return true;
+#else
+ return false;
+#endif
+}
+static void __init xen_init_cpuid_mask(void)
+{
+ unsigned int ax, bx, cx, dx;
+ unsigned int xsave_mask;
+
+ cpuid_leaf1_edx_mask =
+ ~((1 << X86_FEATURE_MTRR) | /* disable MTRR */
+ (1 << X86_FEATURE_ACC)); /* thermal monitoring */
+
+ if (!xen_initial_domain())
+ cpuid_leaf1_edx_mask &=
+ ~((1 << X86_FEATURE_ACPI)); /* disable ACPI */
+
+ cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_X2APIC % 32));
+
+ ax = 1;
+ cx = 0;
+ cpuid(1, &ax, &bx, &cx, &dx);
+
+ xsave_mask =
+ (1 << (X86_FEATURE_XSAVE % 32)) |
+ (1 << (X86_FEATURE_OSXSAVE % 32));
+
+ /* Xen will set CR4.OSXSAVE if supported and not disabled by force */
+ if ((cx & xsave_mask) != xsave_mask)
+ cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */
+ if (xen_check_mwait())
+ cpuid_leaf1_ecx_set_mask = (1 << (X86_FEATURE_MWAIT % 32));
+}
+
+static void xen_set_debugreg(int reg, unsigned long val)
+{
+ HYPERVISOR_set_debugreg(reg, val);
+}
+
+static unsigned long xen_get_debugreg(int reg)
+{
+ return HYPERVISOR_get_debugreg(reg);
+}
+
+static void xen_end_context_switch(struct task_struct *next)
+{
+ xen_mc_flush();
+ paravirt_end_context_switch(next);
+}
+
+static unsigned long xen_store_tr(void)
+{
+ return 0;
+}
+
+/*
+ * Set the page permissions for a particular virtual address. If the
+ * address is a vmalloc mapping (or other non-linear mapping), then
+ * find the linear mapping of the page and also set its protections to
+ * match.
+ */
+static void set_aliased_prot(void *v, pgprot_t prot)
+{
+ int level;
+ pte_t *ptep;
+ pte_t pte;
+ unsigned long pfn;
+ struct page *page;
+ unsigned char dummy;
+
+ ptep = lookup_address((unsigned long)v, &level);
+ BUG_ON(ptep == NULL);
+
+ pfn = pte_pfn(*ptep);
+ page = pfn_to_page(pfn);
+
+ pte = pfn_pte(pfn, prot);
+
+ /*
+ * Careful: update_va_mapping() will fail if the virtual address
+ * we're poking isn't populated in the page tables. We don't
+ * need to worry about the direct map (that's always in the page
+ * tables), but we need to be careful about vmap space. In
+ * particular, the top level page table can lazily propagate
+ * entries between processes, so if we've switched mms since we
+ * vmapped the target in the first place, we might not have the
+ * top-level page table entry populated.
+ *
+ * We disable preemption because we want the same mm active when
+ * we probe the target and when we issue the hypercall. We'll
+ * have the same nominal mm, but if we're a kernel thread, lazy
+ * mm dropping could change our pgd.
+ *
+ * Out of an abundance of caution, this uses __get_user() to fault
+ * in the target address just in case there's some obscure case
+ * in which the target address isn't readable.
+ */
+
+ preempt_disable();
+
+ probe_kernel_read(&dummy, v, 1);
+
+ if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
+ BUG();
+
+ if (!PageHighMem(page)) {
+ void *av = __va(PFN_PHYS(pfn));
+
+ if (av != v)
+ if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
+ BUG();
+ } else
+ kmap_flush_unused();
+
+ preempt_enable();
+}
+
+static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
+{
+ const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
+ int i;
+
+ /*
+ * We need to mark the all aliases of the LDT pages RO. We
+ * don't need to call vm_flush_aliases(), though, since that's
+ * only responsible for flushing aliases out the TLBs, not the
+ * page tables, and Xen will flush the TLB for us if needed.
+ *
+ * To avoid confusing future readers: none of this is necessary
+ * to load the LDT. The hypervisor only checks this when the
+ * LDT is faulted in due to subsequent descriptor access.
+ */
+
+ for (i = 0; i < entries; i += entries_per_page)
+ set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
+}
+
+static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
+{
+ const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
+ int i;
+
+ for (i = 0; i < entries; i += entries_per_page)
+ set_aliased_prot(ldt + i, PAGE_KERNEL);
+}
+
+static void xen_set_ldt(const void *addr, unsigned entries)
+{
+ struct mmuext_op *op;
+ struct multicall_space mcs = xen_mc_entry(sizeof(*op));
+
+ trace_xen_cpu_set_ldt(addr, entries);
+
+ op = mcs.args;
+ op->cmd = MMUEXT_SET_LDT;
+ op->arg1.linear_addr = (unsigned long)addr;
+ op->arg2.nr_ents = entries;
+
+ MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
+
+ xen_mc_issue(PARAVIRT_LAZY_CPU);
+}
+
+static void xen_load_gdt(const struct desc_ptr *dtr)
+{
+ unsigned long va = dtr->address;
+ unsigned int size = dtr->size + 1;
+ unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
+ unsigned long frames[pages];
+ int f;
+
+ /*
+ * A GDT can be up to 64k in size, which corresponds to 8192
+ * 8-byte entries, or 16 4k pages..
+ */
+
+ BUG_ON(size > 65536);
+ BUG_ON(va & ~PAGE_MASK);
+
+ for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
+ int level;
+ pte_t *ptep;
+ unsigned long pfn, mfn;
+ void *virt;
+
+ /*
+ * The GDT is per-cpu and is in the percpu data area.
+ * That can be virtually mapped, so we need to do a
+ * page-walk to get the underlying MFN for the
+ * hypercall. The page can also be in the kernel's
+ * linear range, so we need to RO that mapping too.
+ */
+ ptep = lookup_address(va, &level);
+ BUG_ON(ptep == NULL);
+
+ pfn = pte_pfn(*ptep);
+ mfn = pfn_to_mfn(pfn);
+ virt = __va(PFN_PHYS(pfn));
+
+ frames[f] = mfn;
+
+ make_lowmem_page_readonly((void *)va);
+ make_lowmem_page_readonly(virt);
+ }
+
+ if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
+ BUG();
+}
+
+/*
+ * load_gdt for early boot, when the gdt is only mapped once
+ */
+static void __init xen_load_gdt_boot(const struct desc_ptr *dtr)
+{
+ unsigned long va = dtr->address;
+ unsigned int size = dtr->size + 1;
+ unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
+ unsigned long frames[pages];
+ int f;
+
+ /*
+ * A GDT can be up to 64k in size, which corresponds to 8192
+ * 8-byte entries, or 16 4k pages..
+ */
+
+ BUG_ON(size > 65536);
+ BUG_ON(va & ~PAGE_MASK);
+
+ for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
+ pte_t pte;
+ unsigned long pfn, mfn;
+
+ pfn = virt_to_pfn(va);
+ mfn = pfn_to_mfn(pfn);
+
+ pte = pfn_pte(pfn, PAGE_KERNEL_RO);
+
+ if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0))
+ BUG();
+
+ frames[f] = mfn;
+ }
+
+ if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
+ BUG();
+}
+
+static inline bool desc_equal(const struct desc_struct *d1,
+ const struct desc_struct *d2)
+{
+ return d1->a == d2->a && d1->b == d2->b;
+}
+
+static void load_TLS_descriptor(struct thread_struct *t,
+ unsigned int cpu, unsigned int i)
+{
+ struct desc_struct *shadow = &per_cpu(shadow_tls_desc, cpu).desc[i];
+ struct desc_struct *gdt;
+ xmaddr_t maddr;
+ struct multicall_space mc;
+
+ if (desc_equal(shadow, &t->tls_array[i]))
+ return;
+
+ *shadow = t->tls_array[i];
+
+ gdt = get_cpu_gdt_rw(cpu);
+ maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
+ mc = __xen_mc_entry(0);
+
+ MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
+}
+
+static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
+{
+ /*
+ * XXX sleazy hack: If we're being called in a lazy-cpu zone
+ * and lazy gs handling is enabled, it means we're in a
+ * context switch, and %gs has just been saved. This means we
+ * can zero it out to prevent faults on exit from the
+ * hypervisor if the next process has no %gs. Either way, it
+ * has been saved, and the new value will get loaded properly.
+ * This will go away as soon as Xen has been modified to not
+ * save/restore %gs for normal hypercalls.
+ *
+ * On x86_64, this hack is not used for %gs, because gs points
+ * to KERNEL_GS_BASE (and uses it for PDA references), so we
+ * must not zero %gs on x86_64
+ *
+ * For x86_64, we need to zero %fs, otherwise we may get an
+ * exception between the new %fs descriptor being loaded and
+ * %fs being effectively cleared at __switch_to().
+ */
+ if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
+#ifdef CONFIG_X86_32
+ lazy_load_gs(0);
+#else
+ loadsegment(fs, 0);
+#endif
+ }
+
+ xen_mc_batch();
+
+ load_TLS_descriptor(t, cpu, 0);
+ load_TLS_descriptor(t, cpu, 1);
+ load_TLS_descriptor(t, cpu, 2);
+
+ xen_mc_issue(PARAVIRT_LAZY_CPU);
+}
+
+#ifdef CONFIG_X86_64
+static void xen_load_gs_index(unsigned int idx)
+{
+ if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
+ BUG();
+}
+#endif
+
+static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
+ const void *ptr)
+{
+ xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]);
+ u64 entry = *(u64 *)ptr;
+
+ trace_xen_cpu_write_ldt_entry(dt, entrynum, entry);
+
+ preempt_disable();
+
+ xen_mc_flush();
+ if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
+ BUG();
+
+ preempt_enable();
+}
+
+static int cvt_gate_to_trap(int vector, const gate_desc *val,
+ struct trap_info *info)
+{
+ unsigned long addr;
+
+ if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
+ return 0;
+
+ info->vector = vector;
+
+ addr = gate_offset(*val);
+#ifdef CONFIG_X86_64
+ /*
+ * Look for known traps using IST, and substitute them
+ * appropriately. The debugger ones are the only ones we care
+ * about. Xen will handle faults like double_fault,
+ * so we should never see them. Warn if
+ * there's an unexpected IST-using fault handler.
+ */
+ if (addr == (unsigned long)debug)
+ addr = (unsigned long)xen_debug;
+ else if (addr == (unsigned long)int3)
+ addr = (unsigned long)xen_int3;
+ else if (addr == (unsigned long)stack_segment)
+ addr = (unsigned long)xen_stack_segment;
+ else if (addr == (unsigned long)double_fault) {
+ /* Don't need to handle these */
+ return 0;
+#ifdef CONFIG_X86_MCE
+ } else if (addr == (unsigned long)machine_check) {
+ /*
+ * when xen hypervisor inject vMCE to guest,
+ * use native mce handler to handle it
+ */
+ ;
+#endif
+ } else if (addr == (unsigned long)nmi)
+ /*
+ * Use the native version as well.
+ */
+ ;
+ else {
+ /* Some other trap using IST? */
+ if (WARN_ON(val->ist != 0))
+ return 0;
+ }
+#endif /* CONFIG_X86_64 */
+ info->address = addr;
+
+ info->cs = gate_segment(*val);
+ info->flags = val->dpl;
+ /* interrupt gates clear IF */
+ if (val->type == GATE_INTERRUPT)
+ info->flags |= 1 << 2;
+
+ return 1;
+}
+
+/* Locations of each CPU's IDT */
+static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
+
+/* Set an IDT entry. If the entry is part of the current IDT, then
+ also update Xen. */
+static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
+{
+ unsigned long p = (unsigned long)&dt[entrynum];
+ unsigned long start, end;
+
+ trace_xen_cpu_write_idt_entry(dt, entrynum, g);
+
+ preempt_disable();
+
+ start = __this_cpu_read(idt_desc.address);
+ end = start + __this_cpu_read(idt_desc.size) + 1;
+
+ xen_mc_flush();
+
+ native_write_idt_entry(dt, entrynum, g);
+
+ if (p >= start && (p + 8) <= end) {
+ struct trap_info info[2];
+
+ info[1].address = 0;
+
+ if (cvt_gate_to_trap(entrynum, g, &info[0]))
+ if (HYPERVISOR_set_trap_table(info))
+ BUG();
+ }
+
+ preempt_enable();
+}
+
+static void xen_convert_trap_info(const struct desc_ptr *desc,
+ struct trap_info *traps)
+{
+ unsigned in, out, count;
+
+ count = (desc->size+1) / sizeof(gate_desc);
+ BUG_ON(count > 256);
+
+ for (in = out = 0; in < count; in++) {
+ gate_desc *entry = (gate_desc *)(desc->address) + in;
+
+ if (cvt_gate_to_trap(in, entry, &traps[out]))
+ out++;
+ }
+ traps[out].address = 0;
+}
+
+void xen_copy_trap_info(struct trap_info *traps)
+{
+ const struct desc_ptr *desc = this_cpu_ptr(&idt_desc);
+
+ xen_convert_trap_info(desc, traps);
+}
+
+/* Load a new IDT into Xen. In principle this can be per-CPU, so we
+ hold a spinlock to protect the static traps[] array (static because
+ it avoids allocation, and saves stack space). */
+static void xen_load_idt(const struct desc_ptr *desc)
+{
+ static DEFINE_SPINLOCK(lock);
+ static struct trap_info traps[257];
+
+ trace_xen_cpu_load_idt(desc);
+
+ spin_lock(&lock);
+
+ memcpy(this_cpu_ptr(&idt_desc), desc, sizeof(idt_desc));
+
+ xen_convert_trap_info(desc, traps);
+
+ xen_mc_flush();
+ if (HYPERVISOR_set_trap_table(traps))
+ BUG();
+
+ spin_unlock(&lock);
+}
+
+/* Write a GDT descriptor entry. Ignore LDT descriptors, since
+ they're handled differently. */
+static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
+ const void *desc, int type)
+{
+ trace_xen_cpu_write_gdt_entry(dt, entry, desc, type);
+
+ preempt_disable();
+
+ switch (type) {
+ case DESC_LDT:
+ case DESC_TSS:
+ /* ignore */
+ break;
+
+ default: {
+ xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]);
+
+ xen_mc_flush();
+ if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
+ BUG();
+ }
+
+ }
+
+ preempt_enable();
+}
+
+/*
+ * Version of write_gdt_entry for use at early boot-time needed to
+ * update an entry as simply as possible.
+ */
+static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry,
+ const void *desc, int type)
+{
+ trace_xen_cpu_write_gdt_entry(dt, entry, desc, type);
+
+ switch (type) {
+ case DESC_LDT:
+ case DESC_TSS:
+ /* ignore */
+ break;
+
+ default: {
+ xmaddr_t maddr = virt_to_machine(&dt[entry]);
+
+ if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
+ dt[entry] = *(struct desc_struct *)desc;
+ }
+
+ }
+}
+
+static void xen_load_sp0(struct tss_struct *tss,
+ struct thread_struct *thread)
+{
+ struct multicall_space mcs;
+
+ mcs = xen_mc_entry(0);
+ MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
+ xen_mc_issue(PARAVIRT_LAZY_CPU);
+ tss->x86_tss.sp0 = thread->sp0;
+}
+
+void xen_set_iopl_mask(unsigned mask)
+{
+ struct physdev_set_iopl set_iopl;
+
+ /* Force the change at ring 0. */
+ set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
+ HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
+}
+
+static void xen_io_delay(void)
+{
+}
+
+static DEFINE_PER_CPU(unsigned long, xen_cr0_value);
+
+static unsigned long xen_read_cr0(void)
+{
+ unsigned long cr0 = this_cpu_read(xen_cr0_value);
+
+ if (unlikely(cr0 == 0)) {
+ cr0 = native_read_cr0();
+ this_cpu_write(xen_cr0_value, cr0);
+ }
+
+ return cr0;
+}
+
+static void xen_write_cr0(unsigned long cr0)
+{
+ struct multicall_space mcs;
+
+ this_cpu_write(xen_cr0_value, cr0);
+
+ /* Only pay attention to cr0.TS; everything else is
+ ignored. */
+ mcs = xen_mc_entry(0);
+
+ MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
+
+ xen_mc_issue(PARAVIRT_LAZY_CPU);
+}
+
+static void xen_write_cr4(unsigned long cr4)
+{
+ cr4 &= ~(X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PCE);
+
+ native_write_cr4(cr4);
+}
+#ifdef CONFIG_X86_64
+static inline unsigned long xen_read_cr8(void)
+{
+ return 0;
+}
+static inline void xen_write_cr8(unsigned long val)
+{
+ BUG_ON(val);
+}
+#endif
+
+static u64 xen_read_msr_safe(unsigned int msr, int *err)
+{
+ u64 val;
+
+ if (pmu_msr_read(msr, &val, err))
+ return val;
+
+ val = native_read_msr_safe(msr, err);
+ switch (msr) {
+ case MSR_IA32_APICBASE:
+#ifdef CONFIG_X86_X2APIC
+ if (!(cpuid_ecx(1) & (1 << (X86_FEATURE_X2APIC & 31))))
+#endif
+ val &= ~X2APIC_ENABLE;
+ break;
+ }
+ return val;
+}
+
+static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
+{
+ int ret;
+
+ ret = 0;
+
+ switch (msr) {
+#ifdef CONFIG_X86_64
+ unsigned which;
+ u64 base;
+
+ case MSR_FS_BASE: which = SEGBASE_FS; goto set;
+ case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set;
+ case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set;
+
+ set:
+ base = ((u64)high << 32) | low;
+ if (HYPERVISOR_set_segment_base(which, base) != 0)
+ ret = -EIO;
+ break;
+#endif
+
+ case MSR_STAR:
+ case MSR_CSTAR:
+ case MSR_LSTAR:
+ case MSR_SYSCALL_MASK:
+ case MSR_IA32_SYSENTER_CS:
+ case MSR_IA32_SYSENTER_ESP:
+ case MSR_IA32_SYSENTER_EIP:
+ /* Fast syscall setup is all done in hypercalls, so
+ these are all ignored. Stub them out here to stop
+ Xen console noise. */
+ break;
+
+ default:
+ if (!pmu_msr_write(msr, low, high, &ret))
+ ret = native_write_msr_safe(msr, low, high);
+ }
+
+ return ret;
+}
+
+static u64 xen_read_msr(unsigned int msr)
+{
+ /*
+ * This will silently swallow a #GP from RDMSR. It may be worth
+ * changing that.
+ */
+ int err;
+
+ return xen_read_msr_safe(msr, &err);
+}
+
+static void xen_write_msr(unsigned int msr, unsigned low, unsigned high)
+{
+ /*
+ * This will silently swallow a #GP from WRMSR. It may be worth
+ * changing that.
+ */
+ xen_write_msr_safe(msr, low, high);
+}
+
+void xen_setup_shared_info(void)
+{
+ if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+ set_fixmap(FIX_PARAVIRT_BOOTMAP,
+ xen_start_info->shared_info);
+
+ HYPERVISOR_shared_info =
+ (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
+ } else
+ HYPERVISOR_shared_info =
+ (struct shared_info *)__va(xen_start_info->shared_info);
+
+#ifndef CONFIG_SMP
+ /* In UP this is as good a place as any to set up shared info */
+ xen_setup_vcpu_info_placement();
+#endif
+
+ xen_setup_mfn_list_list();
+}
+
+/* This is called once we have the cpu_possible_mask */
+void xen_setup_vcpu_info_placement(void)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ /* Set up direct vCPU id mapping for PV guests. */
+ per_cpu(xen_vcpu_id, cpu) = cpu;
+ xen_vcpu_setup(cpu);
+ }
+
+ /*
+ * xen_vcpu_setup managed to place the vcpu_info within the
+ * percpu area for all cpus, so make use of it.
+ */
+ if (xen_have_vcpu_info_placement) {
+ pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
+ pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
+ pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
+ pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
+ pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
+ }
+}
+
+static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
+ unsigned long addr, unsigned len)
+{
+ char *start, *end, *reloc;
+ unsigned ret;
+
+ start = end = reloc = NULL;
+
+#define SITE(op, x) \
+ case PARAVIRT_PATCH(op.x): \
+ if (xen_have_vcpu_info_placement) { \
+ start = (char *)xen_##x##_direct; \
+ end = xen_##x##_direct_end; \
+ reloc = xen_##x##_direct_reloc; \
+ } \
+ goto patch_site
+
+ switch (type) {
+ SITE(pv_irq_ops, irq_enable);
+ SITE(pv_irq_ops, irq_disable);
+ SITE(pv_irq_ops, save_fl);
+ SITE(pv_irq_ops, restore_fl);
+#undef SITE
+
+ patch_site:
+ if (start == NULL || (end-start) > len)
+ goto default_patch;
+
+ ret = paravirt_patch_insns(insnbuf, len, start, end);
+
+ /* Note: because reloc is assigned from something that
+ appears to be an array, gcc assumes it's non-null,
+ but doesn't know its relationship with start and
+ end. */
+ if (reloc > start && reloc < end) {
+ int reloc_off = reloc - start;
+ long *relocp = (long *)(insnbuf + reloc_off);
+ long delta = start - (char *)addr;
+
+ *relocp += delta;
+ }
+ break;
+
+ default_patch:
+ default:
+ ret = paravirt_patch_default(type, clobbers, insnbuf,
+ addr, len);
+ break;
+ }
+
+ return ret;
+}
+
+static const struct pv_info xen_info __initconst = {
+ .shared_kernel_pmd = 0,
+
+#ifdef CONFIG_X86_64
+ .extra_user_64bit_cs = FLAT_USER_CS64,
+#endif
+ .name = "Xen",
+};
+
+static const struct pv_init_ops xen_init_ops __initconst = {
+ .patch = xen_patch,
+};
+
+static const struct pv_cpu_ops xen_cpu_ops __initconst = {
+ .cpuid = xen_cpuid,
+
+ .set_debugreg = xen_set_debugreg,
+ .get_debugreg = xen_get_debugreg,
+
+ .read_cr0 = xen_read_cr0,
+ .write_cr0 = xen_write_cr0,
+
+ .read_cr4 = native_read_cr4,
+ .write_cr4 = xen_write_cr4,
+
+#ifdef CONFIG_X86_64
+ .read_cr8 = xen_read_cr8,
+ .write_cr8 = xen_write_cr8,
+#endif
+
+ .wbinvd = native_wbinvd,
+
+ .read_msr = xen_read_msr,
+ .write_msr = xen_write_msr,
+
+ .read_msr_safe = xen_read_msr_safe,
+ .write_msr_safe = xen_write_msr_safe,
+
+ .read_pmc = xen_read_pmc,
+
+ .iret = xen_iret,
+#ifdef CONFIG_X86_64
+ .usergs_sysret64 = xen_sysret64,
+#endif
+
+ .load_tr_desc = paravirt_nop,
+ .set_ldt = xen_set_ldt,
+ .load_gdt = xen_load_gdt,
+ .load_idt = xen_load_idt,
+ .load_tls = xen_load_tls,
+#ifdef CONFIG_X86_64
+ .load_gs_index = xen_load_gs_index,
+#endif
+
+ .alloc_ldt = xen_alloc_ldt,
+ .free_ldt = xen_free_ldt,
+
+ .store_idt = native_store_idt,
+ .store_tr = xen_store_tr,
+
+ .write_ldt_entry = xen_write_ldt_entry,
+ .write_gdt_entry = xen_write_gdt_entry,
+ .write_idt_entry = xen_write_idt_entry,
+ .load_sp0 = xen_load_sp0,
+
+ .set_iopl_mask = xen_set_iopl_mask,
+ .io_delay = xen_io_delay,
+
+ /* Xen takes care of %gs when switching to usermode for us */
+ .swapgs = paravirt_nop,
+
+ .start_context_switch = paravirt_start_context_switch,
+ .end_context_switch = xen_end_context_switch,
+};
+
+static void xen_restart(char *msg)
+{
+ xen_reboot(SHUTDOWN_reboot);
+}
+
+static void xen_machine_halt(void)
+{
+ xen_reboot(SHUTDOWN_poweroff);
+}
+
+static void xen_machine_power_off(void)
+{
+ if (pm_power_off)
+ pm_power_off();
+ xen_reboot(SHUTDOWN_poweroff);
+}
+
+static void xen_crash_shutdown(struct pt_regs *regs)
+{
+ xen_reboot(SHUTDOWN_crash);
+}
+
+static const struct machine_ops xen_machine_ops __initconst = {
+ .restart = xen_restart,
+ .halt = xen_machine_halt,
+ .power_off = xen_machine_power_off,
+ .shutdown = xen_machine_halt,
+ .crash_shutdown = xen_crash_shutdown,
+ .emergency_restart = xen_emergency_restart,
+};
+
+static unsigned char xen_get_nmi_reason(void)
+{
+ unsigned char reason = 0;
+
+ /* Construct a value which looks like it came from port 0x61. */
+ if (test_bit(_XEN_NMIREASON_io_error,
+ &HYPERVISOR_shared_info->arch.nmi_reason))
+ reason |= NMI_REASON_IOCHK;
+ if (test_bit(_XEN_NMIREASON_pci_serr,
+ &HYPERVISOR_shared_info->arch.nmi_reason))
+ reason |= NMI_REASON_SERR;
+
+ return reason;
+}
+
+static void __init xen_boot_params_init_edd(void)
+{
+#if IS_ENABLED(CONFIG_EDD)
+ struct xen_platform_op op;
+ struct edd_info *edd_info;
+ u32 *mbr_signature;
+ unsigned nr;
+ int ret;
+
+ edd_info = boot_params.eddbuf;
+ mbr_signature = boot_params.edd_mbr_sig_buffer;
+
+ op.cmd = XENPF_firmware_info;
+
+ op.u.firmware_info.type = XEN_FW_DISK_INFO;
+ for (nr = 0; nr < EDDMAXNR; nr++) {
+ struct edd_info *info = edd_info + nr;
+
+ op.u.firmware_info.index = nr;
+ info->params.length = sizeof(info->params);
+ set_xen_guest_handle(op.u.firmware_info.u.disk_info.edd_params,
+ &info->params);
+ ret = HYPERVISOR_platform_op(&op);
+ if (ret)
+ break;
+
+#define C(x) info->x = op.u.firmware_info.u.disk_info.x
+ C(device);
+ C(version);
+ C(interface_support);
+ C(legacy_max_cylinder);
+ C(legacy_max_head);
+ C(legacy_sectors_per_track);
+#undef C
+ }
+ boot_params.eddbuf_entries = nr;
+
+ op.u.firmware_info.type = XEN_FW_DISK_MBR_SIGNATURE;
+ for (nr = 0; nr < EDD_MBR_SIG_MAX; nr++) {
+ op.u.firmware_info.index = nr;
+ ret = HYPERVISOR_platform_op(&op);
+ if (ret)
+ break;
+ mbr_signature[nr] = op.u.firmware_info.u.disk_mbr_signature.mbr_signature;
+ }
+ boot_params.edd_mbr_sig_buf_entries = nr;
+#endif
+}
+
+/*
+ * Set up the GDT and segment registers for -fstack-protector. Until
+ * we do this, we have to be careful not to call any stack-protected
+ * function, which is most of the kernel.
+ */
+static void xen_setup_gdt(int cpu)
+{
+ pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot;
+ pv_cpu_ops.load_gdt = xen_load_gdt_boot;
+
+ setup_stack_canary_segment(0);
+ switch_to_new_gdt(0);
+
+ pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry;
+ pv_cpu_ops.load_gdt = xen_load_gdt;
+}
+
+static void __init xen_dom0_set_legacy_features(void)
+{
+ x86_platform.legacy.rtc = 1;
+}
+
+/* First C function to be called on Xen boot */
+asmlinkage __visible void __init xen_start_kernel(void)
+{
+ struct physdev_set_iopl set_iopl;
+ unsigned long initrd_start = 0;
+ int rc;
+
+ if (!xen_start_info)
+ return;
+
+ xen_domain_type = XEN_PV_DOMAIN;
+
+ xen_setup_features();
+
+ xen_setup_machphys_mapping();
+
+ /* Install Xen paravirt ops */
+ pv_info = xen_info;
+ pv_init_ops = xen_init_ops;
+ pv_cpu_ops = xen_cpu_ops;
+
+ x86_platform.get_nmi_reason = xen_get_nmi_reason;
+
+ x86_init.resources.memory_setup = xen_memory_setup;
+ x86_init.oem.arch_setup = xen_arch_setup;
+ x86_init.oem.banner = xen_banner;
+
+ xen_init_time_ops();
+
+ /*
+ * Set up some pagetable state before starting to set any ptes.
+ */
+
+ xen_init_mmu_ops();
+
+ /* Prevent unwanted bits from being set in PTEs. */
+ __supported_pte_mask &= ~_PAGE_GLOBAL;
+
+ /*
+ * Prevent page tables from being allocated in highmem, even
+ * if CONFIG_HIGHPTE is enabled.
+ */
+ __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
+
+ /* Work out if we support NX */
+ x86_configure_nx();
+
+ /* Get mfn list */
+ xen_build_dynamic_phys_to_machine();
+
+ /*
+ * Set up kernel GDT and segment registers, mainly so that
+ * -fstack-protector code can be executed.
+ */
+ xen_setup_gdt(0);
+
+ xen_init_irq_ops();
+ xen_init_cpuid_mask();
+
+#ifdef CONFIG_X86_LOCAL_APIC
+ /*
+ * set up the basic apic ops.
+ */
+ xen_init_apic();
+#endif
+
+ if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
+ pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
+ pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
+ }
+
+ machine_ops = xen_machine_ops;
+
+ /*
+ * The only reliable way to retain the initial address of the
+ * percpu gdt_page is to remember it here, so we can go and
+ * mark it RW later, when the initial percpu area is freed.
+ */
+ xen_initial_gdt = &per_cpu(gdt_page, 0);
+
+ xen_smp_init();
+
+#ifdef CONFIG_ACPI_NUMA
+ /*
+ * The pages we from Xen are not related to machine pages, so
+ * any NUMA information the kernel tries to get from ACPI will
+ * be meaningless. Prevent it from trying.
+ */
+ acpi_numa = -1;
+#endif
+ /* Don't do the full vcpu_info placement stuff until we have a
+ possible map and a non-dummy shared_info. */
+ per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
+
+ 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,
+ xen_start_info->nr_pages);
+ xen_reserve_special_pages();
+
+ /* keep using Xen gdt for now; no urgent need to change it */
+
+#ifdef CONFIG_X86_32
+ pv_info.kernel_rpl = 1;
+ if (xen_feature(XENFEAT_supervisor_mode_kernel))
+ pv_info.kernel_rpl = 0;
+#else
+ pv_info.kernel_rpl = 0;
+#endif
+ /* set the limit of our address space */
+ xen_reserve_top();
+
+ /*
+ * We used to do this in xen_arch_setup, but that is too late
+ * on AMD were early_cpu_init (run before ->arch_setup()) calls
+ * early_amd_init which pokes 0xcf8 port.
+ */
+ set_iopl.iopl = 1;
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
+ if (rc != 0)
+ xen_raw_printk("physdev_op failed %d\n", rc);
+
+#ifdef CONFIG_X86_32
+ /* set up basic CPUID stuff */
+ cpu_detect(&new_cpu_data);
+ set_cpu_cap(&new_cpu_data, X86_FEATURE_FPU);
+ new_cpu_data.x86_capability[CPUID_1_EDX] = cpuid_edx(1);
+#endif
+
+ if (xen_start_info->mod_start) {
+ if (xen_start_info->flags & SIF_MOD_START_PFN)
+ initrd_start = PFN_PHYS(xen_start_info->mod_start);
+ else
+ initrd_start = __pa(xen_start_info->mod_start);
+ }
+
+ /* Poke various useful things into boot_params */
+ boot_params.hdr.type_of_loader = (9 << 4) | 0;
+ boot_params.hdr.ramdisk_image = initrd_start;
+ boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
+ boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
+ boot_params.hdr.hardware_subarch = X86_SUBARCH_XEN;
+
+ if (!xen_initial_domain()) {
+ add_preferred_console("xenboot", 0, NULL);
+ add_preferred_console("tty", 0, NULL);
+ add_preferred_console("hvc", 0, NULL);
+ if (pci_xen)
+ x86_init.pci.arch_init = pci_xen_init;
+ } else {
+ const struct dom0_vga_console_info *info =
+ (void *)((char *)xen_start_info +
+ xen_start_info->console.dom0.info_off);
+ struct xen_platform_op op = {
+ .cmd = XENPF_firmware_info,
+ .interface_version = XENPF_INTERFACE_VERSION,
+ .u.firmware_info.type = XEN_FW_KBD_SHIFT_FLAGS,
+ };
+
+ x86_platform.set_legacy_features =
+ xen_dom0_set_legacy_features;
+ xen_init_vga(info, xen_start_info->console.dom0.info_size);
+ xen_start_info->console.domU.mfn = 0;
+ xen_start_info->console.domU.evtchn = 0;
+
+ if (HYPERVISOR_platform_op(&op) == 0)
+ boot_params.kbd_status = op.u.firmware_info.u.kbd_shift_flags;
+
+ /* Make sure ACS will be enabled */
+ pci_request_acs();
+
+ xen_acpi_sleep_register();
+
+ /* Avoid searching for BIOS MP tables */
+ x86_init.mpparse.find_smp_config = x86_init_noop;
+ x86_init.mpparse.get_smp_config = x86_init_uint_noop;
+
+ xen_boot_params_init_edd();
+ }
+#ifdef CONFIG_PCI
+ /* PCI BIOS service won't work from a PV guest. */
+ pci_probe &= ~PCI_PROBE_BIOS;
+#endif
+ xen_raw_console_write("about to get started...\n");
+
+ /* Let's presume PV guests always boot on vCPU with id 0. */
+ per_cpu(xen_vcpu_id, 0) = 0;
+
+ xen_setup_runstate_info(0);
+
+ xen_efi_init();
+
+ /* Start the world */
+#ifdef CONFIG_X86_32
+ i386_start_kernel();
+#else
+ cr4_init_shadow(); /* 32b kernel does this in i386_start_kernel() */
+ x86_64_start_reservations((char *)__pa_symbol(&boot_params));
+#endif
+}
+
+static int xen_cpu_up_prepare_pv(unsigned int cpu)
+{
+ int rc;
+
+ xen_setup_timer(cpu);
+
+ rc = xen_smp_intr_init(cpu);
+ if (rc) {
+ WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n",
+ cpu, rc);
+ return rc;
+ }
+ return 0;
+}
+
+static int xen_cpu_dead_pv(unsigned int cpu)
+{
+ xen_smp_intr_free(cpu);
+
+ xen_teardown_timer(cpu);
+
+ return 0;
+}
+
+static uint32_t __init xen_platform_pv(void)
+{
+ if (xen_pv_domain())
+ return xen_cpuid_base();
+
+ return 0;
+}
+
+static void xen_set_cpu_features(struct cpuinfo_x86 *c)
+{
+ clear_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
+ set_cpu_cap(c, X86_FEATURE_XENPV);
+}
+
+const struct hypervisor_x86 x86_hyper_xen_pv = {
+ .name = "Xen PV",
+ .detect = xen_platform_pv,
+ .set_cpu_features = xen_set_cpu_features,
+ .pin_vcpu = xen_pin_vcpu,
+};
+EXPORT_SYMBOL(x86_hyper_xen_pv);
projects / platform / kernel / linux-rpi3.git / commitdiff