Merge tag 'for-linus-5.11-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
- A series to fix a regression when running as a fully virtualized
guest on an old Xen hypervisor not supporting PV interrupt callbacks
for HVM guests.
- A patch to add support to query Xen resource sizes (setting was
possible already) from user mode.
* tag 'for-linus-5.11-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/xen: Fix xen_hvm_smp_init() when vector callback not available
x86/xen: Don't register Xen IPIs when they aren't going to be used
x86/xen: Add xen_no_vector_callback option to test PCI INTX delivery
xen: Set platform PCI device INTX affinity to CPU0
xen: Fix event channel callback via INTX/GSI
xen/privcmd: allow fetching resource sizes
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 9e3cdb2..a10b545 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -5972,6 +5972,10 @@
This option is obsoleted by the "nopv" option, which
has equivalent effect for XEN platform.
+ xen_no_vector_callback
+ [KNL,X86,XEN] Disable the vector callback for Xen
+ event channel interrupts.
+
xen_scrub_pages= [XEN]
Boolean option to control scrubbing pages before giving them back
to Xen, for use by other domains. Can be also changed at runtime
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index 60e901c..5a957a9 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -371,7 +371,7 @@
}
gnttab_init();
if (!xen_initial_domain())
- xenbus_probe(NULL);
+ xenbus_probe();
/*
* Making sure board specific code will not set up ops for
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index 9e87ab0..e68ea5f 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -164,10 +164,10 @@
else
per_cpu(xen_vcpu_id, cpu) = cpu;
rc = xen_vcpu_setup(cpu);
- if (rc)
+ if (rc || !xen_have_vector_callback)
return rc;
- if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
+ if (xen_feature(XENFEAT_hvm_safe_pvclock))
xen_setup_timer(cpu);
rc = xen_smp_intr_init(cpu);
@@ -188,6 +188,8 @@
return 0;
}
+static bool no_vector_callback __initdata;
+
static void __init xen_hvm_guest_init(void)
{
if (xen_pv_domain())
@@ -207,7 +209,7 @@
xen_panic_handler_init();
- if (xen_feature(XENFEAT_hvm_callback_vector))
+ if (!no_vector_callback && xen_feature(XENFEAT_hvm_callback_vector))
xen_have_vector_callback = 1;
xen_hvm_smp_init();
@@ -233,6 +235,13 @@
}
early_param("xen_nopv", xen_parse_nopv);
+static __init int xen_parse_no_vector_callback(char *arg)
+{
+ no_vector_callback = true;
+ return 0;
+}
+early_param("xen_no_vector_callback", xen_parse_no_vector_callback);
+
bool __init xen_hvm_need_lapic(void)
{
if (xen_pv_domain())
diff --git a/arch/x86/xen/smp_hvm.c b/arch/x86/xen/smp_hvm.c
index f5e7db4..056430a 100644
--- a/arch/x86/xen/smp_hvm.c
+++ b/arch/x86/xen/smp_hvm.c
@@ -33,9 +33,11 @@
int cpu;
native_smp_prepare_cpus(max_cpus);
- WARN_ON(xen_smp_intr_init(0));
- xen_init_lock_cpu(0);
+ if (xen_have_vector_callback) {
+ WARN_ON(xen_smp_intr_init(0));
+ xen_init_lock_cpu(0);
+ }
for_each_possible_cpu(cpu) {
if (cpu == 0)
@@ -50,9 +52,11 @@
static void xen_hvm_cpu_die(unsigned int cpu)
{
if (common_cpu_die(cpu) == 0) {
- xen_smp_intr_free(cpu);
- xen_uninit_lock_cpu(cpu);
- xen_teardown_timer(cpu);
+ if (xen_have_vector_callback) {
+ xen_smp_intr_free(cpu);
+ xen_uninit_lock_cpu(cpu);
+ xen_teardown_timer(cpu);
+ }
}
}
#else
@@ -64,14 +68,17 @@
void __init xen_hvm_smp_init(void)
{
- if (!xen_have_vector_callback)
- return;
-
+ smp_ops.smp_prepare_boot_cpu = xen_hvm_smp_prepare_boot_cpu;
smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
- smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
+ smp_ops.smp_cpus_done = xen_smp_cpus_done;
smp_ops.cpu_die = xen_hvm_cpu_die;
+
+ if (!xen_have_vector_callback) {
+ nopvspin = true;
+ return;
+ }
+
+ smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
- smp_ops.smp_prepare_boot_cpu = xen_hvm_smp_prepare_boot_cpu;
- smp_ops.smp_cpus_done = xen_smp_cpus_done;
}
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index a803033..e850f79 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -2060,16 +2060,6 @@
.irq_ack = ack_dynirq,
};
-int xen_set_callback_via(uint64_t via)
-{
- struct xen_hvm_param a;
- a.domid = DOMID_SELF;
- a.index = HVM_PARAM_CALLBACK_IRQ;
- a.value = via;
- return HYPERVISOR_hvm_op(HVMOP_set_param, &a);
-}
-EXPORT_SYMBOL_GPL(xen_set_callback_via);
-
#ifdef CONFIG_XEN_PVHVM
/* Vector callbacks are better than PCI interrupts to receive event
* channel notifications because we can receive vector callbacks on any
diff --git a/drivers/xen/platform-pci.c b/drivers/xen/platform-pci.c
index dd911e1..18f0ed8 100644
--- a/drivers/xen/platform-pci.c
+++ b/drivers/xen/platform-pci.c
@@ -132,6 +132,13 @@
dev_warn(&pdev->dev, "request_irq failed err=%d\n", ret);
goto out;
}
+ /*
+ * It doesn't strictly *have* to run on CPU0 but it sure
+ * as hell better process the event channel ports delivered
+ * to CPU0.
+ */
+ irq_set_affinity(pdev->irq, cpumask_of(0));
+
callback_via = get_callback_via(pdev);
ret = xen_set_callback_via(callback_via);
if (ret) {
@@ -149,7 +156,6 @@
ret = gnttab_init();
if (ret)
goto grant_out;
- xenbus_probe(NULL);
return 0;
grant_out:
gnttab_free_auto_xlat_frames();
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index b0c73c5..720a7b7 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -717,14 +717,15 @@
return 0;
}
-static long privcmd_ioctl_mmap_resource(struct file *file, void __user *udata)
+static long privcmd_ioctl_mmap_resource(struct file *file,
+ struct privcmd_mmap_resource __user *udata)
{
struct privcmd_data *data = file->private_data;
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
struct privcmd_mmap_resource kdata;
xen_pfn_t *pfns = NULL;
- struct xen_mem_acquire_resource xdata;
+ struct xen_mem_acquire_resource xdata = { };
int rc;
if (copy_from_user(&kdata, udata, sizeof(kdata)))
@@ -734,6 +735,22 @@
if (data->domid != DOMID_INVALID && data->domid != kdata.dom)
return -EPERM;
+ /* Both fields must be set or unset */
+ if (!!kdata.addr != !!kdata.num)
+ return -EINVAL;
+
+ xdata.domid = kdata.dom;
+ xdata.type = kdata.type;
+ xdata.id = kdata.id;
+
+ if (!kdata.addr && !kdata.num) {
+ /* Query the size of the resource. */
+ rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata);
+ if (rc)
+ return rc;
+ return __put_user(xdata.nr_frames, &udata->num);
+ }
+
mmap_write_lock(mm);
vma = find_vma(mm, kdata.addr);
@@ -768,10 +785,6 @@
} else
vma->vm_private_data = PRIV_VMA_LOCKED;
- memset(&xdata, 0, sizeof(xdata));
- xdata.domid = kdata.dom;
- xdata.type = kdata.type;
- xdata.id = kdata.id;
xdata.frame = kdata.idx;
xdata.nr_frames = kdata.num;
set_xen_guest_handle(xdata.frame_list, pfns);
diff --git a/drivers/xen/xenbus/xenbus.h b/drivers/xen/xenbus/xenbus.h
index 2a93b7c..dc15373 100644
--- a/drivers/xen/xenbus/xenbus.h
+++ b/drivers/xen/xenbus/xenbus.h
@@ -115,6 +115,7 @@
const char *type,
const char *nodename);
int xenbus_probe_devices(struct xen_bus_type *bus);
+void xenbus_probe(void);
void xenbus_dev_changed(const char *node, struct xen_bus_type *bus);
diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c
index eb5151f..e5fda02 100644
--- a/drivers/xen/xenbus/xenbus_comms.c
+++ b/drivers/xen/xenbus/xenbus_comms.c
@@ -57,16 +57,8 @@
static int xenbus_irq;
static struct task_struct *xenbus_task;
-static DECLARE_WORK(probe_work, xenbus_probe);
-
-
static irqreturn_t wake_waiting(int irq, void *unused)
{
- if (unlikely(xenstored_ready == 0)) {
- xenstored_ready = 1;
- schedule_work(&probe_work);
- }
-
wake_up(&xb_waitq);
return IRQ_HANDLED;
}
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 44634d9..c8f0282 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -683,29 +683,76 @@
}
EXPORT_SYMBOL_GPL(unregister_xenstore_notifier);
-void xenbus_probe(struct work_struct *unused)
+void xenbus_probe(void)
{
xenstored_ready = 1;
+ /*
+ * In the HVM case, xenbus_init() deferred its call to
+ * xs_init() in case callbacks were not operational yet.
+ * So do it now.
+ */
+ if (xen_store_domain_type == XS_HVM)
+ xs_init();
+
/* Notify others that xenstore is up */
blocking_notifier_call_chain(&xenstore_chain, 0, NULL);
}
-EXPORT_SYMBOL_GPL(xenbus_probe);
+
+/*
+ * Returns true when XenStore init must be deferred in order to
+ * allow the PCI platform device to be initialised, before we
+ * can actually have event channel interrupts working.
+ */
+static bool xs_hvm_defer_init_for_callback(void)
+{
+#ifdef CONFIG_XEN_PVHVM
+ return xen_store_domain_type == XS_HVM &&
+ !xen_have_vector_callback;
+#else
+ return false;
+#endif
+}
static int __init xenbus_probe_initcall(void)
{
- if (!xen_domain())
- return -ENODEV;
+ /*
+ * Probe XenBus here in the XS_PV case, and also XS_HVM unless we
+ * need to wait for the platform PCI device to come up.
+ */
+ if (xen_store_domain_type == XS_PV ||
+ (xen_store_domain_type == XS_HVM &&
+ !xs_hvm_defer_init_for_callback()))
+ xenbus_probe();
- if (xen_initial_domain() || xen_hvm_domain())
- return 0;
-
- xenbus_probe(NULL);
return 0;
}
-
device_initcall(xenbus_probe_initcall);
+int xen_set_callback_via(uint64_t via)
+{
+ struct xen_hvm_param a;
+ int ret;
+
+ a.domid = DOMID_SELF;
+ a.index = HVM_PARAM_CALLBACK_IRQ;
+ a.value = via;
+
+ ret = HYPERVISOR_hvm_op(HVMOP_set_param, &a);
+ if (ret)
+ return ret;
+
+ /*
+ * If xenbus_probe_initcall() deferred the xenbus_probe()
+ * due to the callback not functioning yet, we can do it now.
+ */
+ if (!xenstored_ready && xs_hvm_defer_init_for_callback())
+ xenbus_probe();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xen_set_callback_via);
+
/* Set up event channel for xenstored which is run as a local process
* (this is normally used only in dom0)
*/
@@ -818,11 +865,17 @@
break;
}
- /* Initialize the interface to xenstore. */
- err = xs_init();
- if (err) {
- pr_warn("Error initializing xenstore comms: %i\n", err);
- goto out_error;
+ /*
+ * HVM domains may not have a functional callback yet. In that
+ * case let xs_init() be called from xenbus_probe(), which will
+ * get invoked at an appropriate time.
+ */
+ if (xen_store_domain_type != XS_HVM) {
+ err = xs_init();
+ if (err) {
+ pr_warn("Error initializing xenstore comms: %i\n", err);
+ goto out_error;
+ }
}
if ((xen_store_domain_type != XS_LOCAL) &&
diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h
index 00c7235..2c43b0ef 100644
--- a/include/xen/xenbus.h
+++ b/include/xen/xenbus.h
@@ -192,7 +192,7 @@
struct work_struct;
-void xenbus_probe(struct work_struct *);
+void xenbus_probe(void);
#define XENBUS_IS_ERR_READ(str) ({ \
if (!IS_ERR(str) && strlen(str) == 0) { \
