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-rw-r--r--arch/x86/include/asm/xen/events.h11
-rw-r--r--arch/x86/pci/xen.c2
-rw-r--r--arch/x86/xen/enlighten_hvm.c12
-rw-r--r--arch/x86/xen/smp_hvm.c5
-rw-r--r--arch/x86/xen/time.c8
-rw-r--r--drivers/xen/events/events_base.c25
-rw-r--r--drivers/xen/platform-pci.c14
7 files changed, 54 insertions, 23 deletions
diff --git a/arch/x86/include/asm/xen/events.h b/arch/x86/include/asm/xen/events.h
index 608a79d5a466..e6911caf5bbf 100644
--- a/arch/x86/include/asm/xen/events.h
+++ b/arch/x86/include/asm/xen/events.h
@@ -20,4 +20,15 @@ static inline int xen_irqs_disabled(struct pt_regs *regs)
/* No need for a barrier -- XCHG is a barrier on x86. */
#define xchg_xen_ulong(ptr, val) xchg((ptr), (val))
+extern int xen_have_vector_callback;
+
+/*
+ * Events delivered via platform PCI interrupts are always
+ * routed to vcpu 0 and hence cannot be rebound.
+ */
+static inline bool xen_support_evtchn_rebind(void)
+{
+ return (!xen_hvm_domain() || xen_have_vector_callback);
+}
+
#endif /* _ASM_X86_XEN_EVENTS_H */
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 292ab0364a89..c4b3646bd04c 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -447,7 +447,7 @@ void __init xen_msi_init(void)
int __init pci_xen_hvm_init(void)
{
- if (!xen_feature(XENFEAT_hvm_pirqs))
+ if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs))
return 0;
#ifdef CONFIG_ACPI
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index 72df54a481d6..078c512b8720 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -18,6 +18,9 @@
#include "mmu.h"
#include "smp.h"
+__read_mostly int xen_have_vector_callback;
+EXPORT_SYMBOL_GPL(xen_have_vector_callback);
+
void __ref xen_hvm_init_shared_info(void)
{
int cpu;
@@ -123,7 +126,7 @@ static int xen_cpu_up_prepare_hvm(unsigned int cpu)
per_cpu(xen_vcpu_id, cpu) = cpu;
xen_vcpu_setup(cpu);
- if (xen_feature(XENFEAT_hvm_safe_pvclock))
+ if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
xen_setup_timer(cpu);
rc = xen_smp_intr_init(cpu);
@@ -139,7 +142,7 @@ static int xen_cpu_dead_hvm(unsigned int cpu)
{
xen_smp_intr_free(cpu);
- if (xen_feature(XENFEAT_hvm_safe_pvclock))
+ if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
xen_teardown_timer(cpu);
return 0;
@@ -156,7 +159,8 @@ static void __init xen_hvm_guest_init(void)
xen_panic_handler_init();
- BUG_ON(!xen_feature(XENFEAT_hvm_callback_vector));
+ 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));
@@ -189,7 +193,7 @@ bool xen_hvm_need_lapic(void)
return false;
if (!xen_hvm_domain())
return false;
- if (xen_feature(XENFEAT_hvm_pirqs))
+ if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback)
return false;
return true;
}
diff --git a/arch/x86/xen/smp_hvm.c b/arch/x86/xen/smp_hvm.c
index 8bed434cd7d7..f18561bbf5c9 100644
--- a/arch/x86/xen/smp_hvm.c
+++ b/arch/x86/xen/smp_hvm.c
@@ -1,5 +1,7 @@
#include <asm/smp.h>
+#include <xen/events.h>
+
#include "xen-ops.h"
#include "smp.h"
@@ -49,6 +51,9 @@ static void xen_hvm_cpu_die(unsigned int cpu)
void __init xen_hvm_smp_init(void)
{
+ if (!xen_have_vector_callback)
+ return;
+
smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
smp_ops.cpu_die = xen_hvm_cpu_die;
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 7a3089285c59..090c7eb4dca9 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -436,6 +436,14 @@ static void xen_hvm_setup_cpu_clockevents(void)
void __init xen_hvm_init_time_ops(void)
{
+ /*
+ * vector callback is needed otherwise we cannot receive interrupts
+ * on cpu > 0 and at this point we don't know how many cpus are
+ * available.
+ */
+ if (!xen_have_vector_callback)
+ return;
+
if (!xen_feature(XENFEAT_hvm_safe_pvclock)) {
printk(KERN_INFO "Xen doesn't support pvclock on HVM,"
"disable pv timer\n");
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 6a53577772c9..b52852f38cff 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -1312,6 +1312,9 @@ static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
if (!VALID_EVTCHN(evtchn))
return -1;
+ if (!xen_support_evtchn_rebind())
+ return -1;
+
/* Send future instances of this interrupt to other vcpu. */
bind_vcpu.port = evtchn;
bind_vcpu.vcpu = xen_vcpu_nr(tcpu);
@@ -1646,14 +1649,20 @@ void xen_callback_vector(void)
int rc;
uint64_t callback_via;
- callback_via = HVM_CALLBACK_VECTOR(HYPERVISOR_CALLBACK_VECTOR);
- rc = xen_set_callback_via(callback_via);
- BUG_ON(rc);
- pr_info("Xen HVM callback vector for event delivery is enabled\n");
- /* in the restore case the vector has already been allocated */
- if (!test_bit(HYPERVISOR_CALLBACK_VECTOR, used_vectors))
- alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR,
- xen_hvm_callback_vector);
+ if (xen_have_vector_callback) {
+ callback_via = HVM_CALLBACK_VECTOR(HYPERVISOR_CALLBACK_VECTOR);
+ rc = xen_set_callback_via(callback_via);
+ if (rc) {
+ pr_err("Request for Xen HVM callback vector failed\n");
+ xen_have_vector_callback = 0;
+ return;
+ }
+ pr_info("Xen HVM callback vector for event delivery is enabled\n");
+ /* in the restore case the vector has already been allocated */
+ if (!test_bit(HYPERVISOR_CALLBACK_VECTOR, used_vectors))
+ alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR,
+ xen_hvm_callback_vector);
+ }
}
#else
void xen_callback_vector(void) {}
diff --git a/drivers/xen/platform-pci.c b/drivers/xen/platform-pci.c
index 2a165cc8a43c..1275df83070f 100644
--- a/drivers/xen/platform-pci.c
+++ b/drivers/xen/platform-pci.c
@@ -90,8 +90,10 @@ static int xen_allocate_irq(struct pci_dev *pdev)
static int platform_pci_resume(struct pci_dev *pdev)
{
int err;
- if (!xen_pv_domain())
+
+ if (xen_have_vector_callback)
return 0;
+
err = xen_set_callback_via(callback_via);
if (err) {
dev_err(&pdev->dev, "platform_pci_resume failure!\n");
@@ -137,15 +139,7 @@ static int platform_pci_probe(struct pci_dev *pdev,
platform_mmio = mmio_addr;
platform_mmiolen = mmio_len;
-
- /*
- * Xen HVM guests always use the vector callback mechanism.
- * L1 Dom0 in a nested Xen environment is a PV guest inside in an
- * HVM environment. It needs the platform-pci driver to get
- * notifications from L0 Xen, but it cannot use the vector callback
- * as it is not exported by L1 Xen.
- */
- if (xen_pv_domain()) {
+ if (!xen_have_vector_callback) {
ret = xen_allocate_irq(pdev);
if (ret) {
dev_warn(&pdev->dev, "request_irq failed err=%d\n", ret);