Merge tag 'for-linus-4.11b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "Fixes for PM under Xen"

* tag 'for-linus-4.11b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/acpi: upload PM state from init-domain to Xen
  xen/acpi: Replace hard coded "ACPI0007"

1 files changed, 27 insertions, 9 deletions

diff --git a/drivers/xen/xen-acpi-processor.c b/drivers/xen/xen-acpi-processor.c
index 4ce10bcca18b..23e391d3ec01 100644
--- a/drivers/xen/xen-acpi-processor.c
+++ b/drivers/xen/xen-acpi-processor.c
@@ -27,10 +27,10 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/types.h>
+#include <linux/syscore_ops.h>
 #include <linux/acpi.h>
 #include <acpi/processor.h>
 #include <xen/xen.h>
-#include <xen/xen-ops.h>
 #include <xen/interface/platform.h>
 #include <asm/xen/hypercall.h>
 
@@ -408,7 +408,7 @@ static int check_acpi_ids(struct acpi_processor *pr_backup)
         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
                             ACPI_UINT32_MAX,
                             read_acpi_id, NULL, NULL, NULL);
-        acpi_get_devices("ACPI0007", read_acpi_id, NULL, NULL);
+        acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, read_acpi_id, NULL, NULL);
 
 upload:
         if (!bitmap_equal(acpi_id_present, acpi_ids_done, nr_acpi_bits)) {
@@ -466,15 +466,33 @@ static int xen_upload_processor_pm_data(void)
         return rc;
 }
 
-static int xen_acpi_processor_resume(struct notifier_block *nb,
-                                     unsigned long action, void *data)
+static void xen_acpi_processor_resume_worker(struct work_struct *dummy)
 {
+        int rc;
+
         bitmap_zero(acpi_ids_done, nr_acpi_bits);
-        return xen_upload_processor_pm_data();
+
+        rc = xen_upload_processor_pm_data();
+        if (rc != 0)
+                pr_info("ACPI data upload failed, error = %d\n", rc);
+}
+
+static void xen_acpi_processor_resume(void)
+{
+        static DECLARE_WORK(wq, xen_acpi_processor_resume_worker);
+
+        /*
+         * xen_upload_processor_pm_data() calls non-atomic code.
+         * However, the context for xen_acpi_processor_resume is syscore
+         * with only the boot CPU online and in an atomic context.
+         *
+         * So defer the upload for some point safer.
+         */
+        schedule_work(&wq);
 }
 
-struct notifier_block xen_acpi_processor_resume_nb = {
-        .notifier_call = xen_acpi_processor_resume,
+static struct syscore_ops xap_syscore_ops = {
+        .resume = xen_acpi_processor_resume,
 };
 
 static int __init xen_acpi_processor_init(void)
@@ -527,7 +545,7 @@ static int __init xen_acpi_processor_init(void)
         if (rc)
                 goto err_unregister;
 
-        xen_resume_notifier_register(&xen_acpi_processor_resume_nb);
+        register_syscore_ops(&xap_syscore_ops);
 
         return 0;
 err_unregister:
@@ -544,7 +562,7 @@ static void __exit xen_acpi_processor_exit(void)
 {
         int i;
 
-        xen_resume_notifier_unregister(&xen_acpi_processor_resume_nb);
+        unregister_syscore_ops(&xap_syscore_ops);
         kfree(acpi_ids_done);
         kfree(acpi_id_present);
         kfree(acpi_id_cst_present);