linux/arch/x86/xen/enlighten_hvm.c

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#include <linux/cpu.h>
#include <linux/kexec.h>
#include <xen/features.h>
#include <xen/events.h>
#include <xen/interface/memory.h>
#include <asm/cpu.h>
#include <asm/smp.h>
#include <asm/reboot.h>
#include <asm/setup.h>
#include <asm/hypervisor.h>
#include <asm/xen/cpuid.h>
#include <asm/xen/hypervisor.h>
#include "xen-ops.h"
#include "mmu.h"
#include "smp.h"
void __ref xen_hvm_init_shared_info(void)
{
struct xen_add_to_physmap xatp;
static struct shared_info *shared_info_page;
if (!shared_info_page)
shared_info_page = (struct shared_info *)
extend_brk(PAGE_SIZE, PAGE_SIZE);
xatp.domid = DOMID_SELF;
xatp.idx = 0;
xatp.space = XENMAPSPACE_shared_info;
xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
BUG();
HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
}
static void __init init_hvm_pv_info(void)
{
int major, minor;
uint32_t eax, ebx, ecx, edx, base;
base = xen_cpuid_base();
eax = cpuid_eax(base + 1);
major = eax >> 16;
minor = eax & 0xffff;
printk(KERN_INFO "Xen version %d.%d.\n", major, minor);
xen_domain_type = XEN_HVM_DOMAIN;
/* PVH set up hypercall page in xen_prepare_pvh(). */
if (xen_pvh_domain())
pv_info.name = "Xen PVH";
else {
u64 pfn;
uint32_t msr;
pv_info.name = "Xen HVM";
msr = cpuid_ebx(base + 2);
pfn = __pa(hypercall_page);
wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
}
xen_setup_features();
cpuid(base + 4, &eax, &ebx, &ecx, &edx);
if (eax & XEN_HVM_CPUID_VCPU_ID_PRESENT)
this_cpu_write(xen_vcpu_id, ebx);
else
this_cpu_write(xen_vcpu_id, smp_processor_id());
}
#ifdef CONFIG_KEXEC_CORE
static void xen_hvm_shutdown(void)
{
native_machine_shutdown();
if (kexec_in_progress)
xen_reboot(SHUTDOWN_soft_reset);
}
static void xen_hvm_crash_shutdown(struct pt_regs *regs)
{
native_machine_crash_shutdown(regs);
xen_reboot(SHUTDOWN_soft_reset);
}
#endif
static int xen_cpu_up_prepare_hvm(unsigned int cpu)
{
int rc;
/*
* This can happen if CPU was offlined earlier and
* offlining timed out in common_cpu_die().
*/
if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
xen_smp_intr_free(cpu);
xen_uninit_lock_cpu(cpu);
}
if (cpu_acpi_id(cpu) != U32_MAX)
per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu);
else
per_cpu(xen_vcpu_id, cpu) = cpu;
xen_vcpu_setup(cpu);
xen: Revert commits da72ff5bfcb0 and 72a9b186292d Recent discussion (http://marc.info/?l=xen-devel&m=149192184523741) established that commit 72a9b186292d ("xen: Remove event channel notification through Xen PCI platform device") (and thus commit da72ff5bfcb0 ("partially revert "xen: Remove event channel notification through Xen PCI platform device"")) are unnecessary and, in fact, prevent HVM guests from booting on Xen releases prior to 4.0 Therefore we revert both of those commits. The summary of that discussion is below: Here is the brief summary of the current situation: Before the offending commit (72a9b186292): 1) INTx does not work because of the reset_watches path. 2) The reset_watches path is only taken if you have Xen > 4.0 3) The Linux Kernel by default will use vector inject if the hypervisor support. So even INTx does not work no body running the kernel with Xen > 4.0 would notice. Unless he explicitly disabled this feature either in the kernel or in Xen (and this can only be disabled by modifying the code, not user-supported way to do it). After the offending commit (+ partial revert): 1) INTx is no longer support for HVM (only for PV guests). 2) Any HVM guest The kernel will not boot on Xen < 4.0 which does not have vector injection support. Since the only other mode supported is INTx which. So based on this summary, I think before commit (72a9b186292) we were in much better position from a user point of view. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-04-24 21:04:53 +02:00
if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
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_hvm(unsigned int cpu)
{
xen_smp_intr_free(cpu);
xen: Revert commits da72ff5bfcb0 and 72a9b186292d Recent discussion (http://marc.info/?l=xen-devel&m=149192184523741) established that commit 72a9b186292d ("xen: Remove event channel notification through Xen PCI platform device") (and thus commit da72ff5bfcb0 ("partially revert "xen: Remove event channel notification through Xen PCI platform device"")) are unnecessary and, in fact, prevent HVM guests from booting on Xen releases prior to 4.0 Therefore we revert both of those commits. The summary of that discussion is below: Here is the brief summary of the current situation: Before the offending commit (72a9b186292): 1) INTx does not work because of the reset_watches path. 2) The reset_watches path is only taken if you have Xen > 4.0 3) The Linux Kernel by default will use vector inject if the hypervisor support. So even INTx does not work no body running the kernel with Xen > 4.0 would notice. Unless he explicitly disabled this feature either in the kernel or in Xen (and this can only be disabled by modifying the code, not user-supported way to do it). After the offending commit (+ partial revert): 1) INTx is no longer support for HVM (only for PV guests). 2) Any HVM guest The kernel will not boot on Xen < 4.0 which does not have vector injection support. Since the only other mode supported is INTx which. So based on this summary, I think before commit (72a9b186292) we were in much better position from a user point of view. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-04-24 21:04:53 +02:00
if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
xen_teardown_timer(cpu);
return 0;
}
static void __init xen_hvm_guest_init(void)
{
if (xen_pv_domain())
return;
init_hvm_pv_info();
xen_hvm_init_shared_info();
xen/pvh*: Support > 32 VCPUs at domain restore When Xen restores a PVHVM or PVH guest, its shared_info only holds up to 32 CPUs. The hypercall VCPUOP_register_vcpu_info allows us to setup per-page areas for VCPUs. This means we can boot PVH* guests with more than 32 VCPUs. During restore the per-cpu structure is allocated freshly by the hypervisor (vcpu_info_mfn is set to INVALID_MFN) so that the newly restored guest can make a VCPUOP_register_vcpu_info hypercall. However, we end up triggering this condition in Xen: /* Run this command on yourself or on other offline VCPUS. */ if ( (v != current) && !test_bit(_VPF_down, &v->pause_flags) ) which means we are unable to setup the per-cpu VCPU structures for running VCPUS. The Linux PV code paths makes this work by iterating over cpu_possible in xen_vcpu_restore() with: 1) is target CPU up (VCPUOP_is_up hypercall?) 2) if yes, then VCPUOP_down to pause it 3) VCPUOP_register_vcpu_info 4) if it was down, then VCPUOP_up to bring it back up With Xen commit 192df6f9122d ("xen/x86: allow HVM guests to use hypercalls to bring up vCPUs") this is available for non-PV guests. As such first check if VCPUOP_is_up is actually possible before trying this dance. As most of this dance code is done already in xen_vcpu_restore() let's make it callable on PV, PVH and PVHVM. Based-on-patch-by: Konrad Wilk <konrad.wilk@oracle.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-06-03 02:05:59 +02:00
/*
* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
* page, we use it in the event channel upcall and in some pvclock
* related functions.
*/
xen_vcpu_info_reset(0);
xen_panic_handler_init();
xen: Revert commits da72ff5bfcb0 and 72a9b186292d Recent discussion (http://marc.info/?l=xen-devel&m=149192184523741) established that commit 72a9b186292d ("xen: Remove event channel notification through Xen PCI platform device") (and thus commit da72ff5bfcb0 ("partially revert "xen: Remove event channel notification through Xen PCI platform device"")) are unnecessary and, in fact, prevent HVM guests from booting on Xen releases prior to 4.0 Therefore we revert both of those commits. The summary of that discussion is below: Here is the brief summary of the current situation: Before the offending commit (72a9b186292): 1) INTx does not work because of the reset_watches path. 2) The reset_watches path is only taken if you have Xen > 4.0 3) The Linux Kernel by default will use vector inject if the hypervisor support. So even INTx does not work no body running the kernel with Xen > 4.0 would notice. Unless he explicitly disabled this feature either in the kernel or in Xen (and this can only be disabled by modifying the code, not user-supported way to do it). After the offending commit (+ partial revert): 1) INTx is no longer support for HVM (only for PV guests). 2) Any HVM guest The kernel will not boot on Xen < 4.0 which does not have vector injection support. Since the only other mode supported is INTx which. So based on this summary, I think before commit (72a9b186292) we were in much better position from a user point of view. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-04-24 21:04:53 +02:00
if (xen_feature(XENFEAT_hvm_callback_vector))
xen_have_vector_callback = 1;
xen_hvm_smp_init();
WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm));
xen_unplug_emulated_devices();
x86_init.irqs.intr_init = xen_init_IRQ;
xen_hvm_init_time_ops();
xen_hvm_init_mmu_ops();
if (xen_pvh_domain())
machine_ops.emergency_restart = xen_emergency_restart;
#ifdef CONFIG_KEXEC_CORE
machine_ops.shutdown = xen_hvm_shutdown;
machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
#endif
}
static bool xen_nopv;
static __init int xen_parse_nopv(char *arg)
{
xen_nopv = true;
return 0;
}
early_param("xen_nopv", xen_parse_nopv);
bool xen_hvm_need_lapic(void)
{
if (xen_nopv)
return false;
if (xen_pv_domain())
return false;
if (!xen_hvm_domain())
return false;
xen: Revert commits da72ff5bfcb0 and 72a9b186292d Recent discussion (http://marc.info/?l=xen-devel&m=149192184523741) established that commit 72a9b186292d ("xen: Remove event channel notification through Xen PCI platform device") (and thus commit da72ff5bfcb0 ("partially revert "xen: Remove event channel notification through Xen PCI platform device"")) are unnecessary and, in fact, prevent HVM guests from booting on Xen releases prior to 4.0 Therefore we revert both of those commits. The summary of that discussion is below: Here is the brief summary of the current situation: Before the offending commit (72a9b186292): 1) INTx does not work because of the reset_watches path. 2) The reset_watches path is only taken if you have Xen > 4.0 3) The Linux Kernel by default will use vector inject if the hypervisor support. So even INTx does not work no body running the kernel with Xen > 4.0 would notice. Unless he explicitly disabled this feature either in the kernel or in Xen (and this can only be disabled by modifying the code, not user-supported way to do it). After the offending commit (+ partial revert): 1) INTx is no longer support for HVM (only for PV guests). 2) Any HVM guest The kernel will not boot on Xen < 4.0 which does not have vector injection support. Since the only other mode supported is INTx which. So based on this summary, I think before commit (72a9b186292) we were in much better position from a user point of view. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-04-24 21:04:53 +02:00
if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback)
return false;
return true;
}
EXPORT_SYMBOL_GPL(xen_hvm_need_lapic);
static uint32_t __init xen_platform_hvm(void)
{
if (xen_pv_domain() || xen_nopv)
return 0;
return xen_cpuid_base();
}
const struct hypervisor_x86 x86_hyper_xen_hvm = {
.name = "Xen HVM",
.detect = xen_platform_hvm,
.init_platform = xen_hvm_guest_init,
.pin_vcpu = xen_pin_vcpu,
.x2apic_available = xen_x2apic_para_available,
};
EXPORT_SYMBOL(x86_hyper_xen_hvm);