Merge tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights:

   - Infrastructure for secure boot on some bare metal Power9 machines.
     The firmware support is still in development, so the code here
     won't actually activate secure boot on any existing systems.

   - A change to xmon (our crash handler / pseudo-debugger) to restrict
     it to read-only mode when the kernel is lockdown'ed, otherwise it's
     trivial to drop into xmon and modify kernel data, such as the
     lockdown state.

   - Support for KASLR on 32-bit BookE machines (Freescale / NXP).

   - Fixes for our flush_icache_range() and __kernel_sync_dicache()
     (VDSO) to work with memory ranges >4GB.

   - Some reworks of the pseries CMM (Cooperative Memory Management)
     driver to make it behave more like other balloon drivers and enable
     some cleanups of generic mm code.

   - A series of fixes to our hardware breakpoint support to properly
     handle unaligned watchpoint addresses.

  Plus a bunch of other smaller improvements, fixes and cleanups.

  Thanks to: Alastair D'Silva, Andrew Donnellan, Aneesh Kumar K.V,
  Anthony Steinhauser, Cédric Le Goater, Chris Packham, Chris Smart,
  Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio
  Carvalho, Daniel Axtens, David Hildenbrand, Deb McLemore, Diana
  Craciun, Eric Richter, Geert Uytterhoeven, Greg Kroah-Hartman, Greg
  Kurz, Gustavo L. F. Walbon, Hari Bathini, Harish, Jason Yan, Krzysztof
  Kozlowski, Leonardo Bras, Mathieu Malaterre, Mauro S. M. Rodrigues,
  Michal Suchanek, Mimi Zohar, Nathan Chancellor, Nathan Lynch, Nayna
  Jain, Nick Desaulniers, Oliver O'Halloran, Qian Cai, Rasmus Villemoes,
  Ravi Bangoria, Sam Bobroff, Santosh Sivaraj, Scott Wood, Thomas Huth,
  Tyrel Datwyler, Vaibhav Jain, Valentin Longchamp, YueHaibing"

* tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (144 commits)
  powerpc/fixmap: fix crash with HIGHMEM
  x86/efi: remove unused variables
  powerpc: Define arch_is_kernel_initmem_freed() for lockdep
  powerpc/prom_init: Use -ffreestanding to avoid a reference to bcmp
  powerpc: Avoid clang warnings around setjmp and longjmp
  powerpc: Don't add -mabi= flags when building with Clang
  powerpc: Fix Kconfig indentation
  powerpc/fixmap: don't clear fixmap area in paging_init()
  selftests/powerpc: spectre_v2 test must be built 64-bit
  powerpc/powernv: Disable native PCIe port management
  powerpc/kexec: Move kexec files into a dedicated subdir.
  powerpc/32: Split kexec low level code out of misc_32.S
  powerpc/sysdev: drop simple gpio
  powerpc/83xx: map IMMR with a BAT.
  powerpc/32s: automatically allocate BAT in setbat()
  powerpc/ioremap: warn on early use of ioremap()
  powerpc: Add support for GENERIC_EARLY_IOREMAP
  powerpc/fixmap: Use __fix_to_virt() instead of fix_to_virt()
  powerpc/8xx: use the fixmapped IMMR in cpm_reset()
  powerpc/8xx: add __init to cpm1 init functions
  ...

1 files changed, 87 insertions, 2 deletions

diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index 38e90270280b..a6ee08009f0f 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -35,6 +35,16 @@
 
 #include "powernv.h"
 
+#define OPAL_MSG_QUEUE_MAX 16
+
+struct opal_msg_node {
+	struct list_head	list;
+	struct opal_msg		msg;
+};
+
+static DEFINE_SPINLOCK(msg_list_lock);
+static LIST_HEAD(msg_list);
+
 /* /sys/firmware/opal */
 struct kobject *opal_kobj;
 
@@ -50,6 +60,8 @@ struct mcheck_recoverable_range {
 	u64 recover_addr;
 };
 
+static int msg_list_size;
+
 static struct mcheck_recoverable_range *mc_recoverable_range;
 static int mc_recoverable_range_len;
 
@@ -237,6 +249,43 @@ static int __init opal_register_exception_handlers(void)
 }
 machine_early_initcall(powernv, opal_register_exception_handlers);
 
+static void queue_replay_msg(void *msg)
+{
+	struct opal_msg_node *msg_node;
+
+	if (msg_list_size < OPAL_MSG_QUEUE_MAX) {
+		msg_node = kzalloc(sizeof(*msg_node), GFP_ATOMIC);
+		if (msg_node) {
+			INIT_LIST_HEAD(&msg_node->list);
+			memcpy(&msg_node->msg, msg, sizeof(struct opal_msg));
+			list_add_tail(&msg_node->list, &msg_list);
+			msg_list_size++;
+		} else
+			pr_warn_once("message queue no memory\n");
+
+		if (msg_list_size >= OPAL_MSG_QUEUE_MAX)
+			pr_warn_once("message queue full\n");
+	}
+}
+
+static void dequeue_replay_msg(enum opal_msg_type msg_type)
+{
+	struct opal_msg_node *msg_node, *tmp;
+
+	list_for_each_entry_safe(msg_node, tmp, &msg_list, list) {
+		if (be32_to_cpu(msg_node->msg.msg_type) != msg_type)
+			continue;
+
+		atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type],
+					msg_type,
+					&msg_node->msg);
+
+		list_del(&msg_node->list);
+		kfree(msg_node);
+		msg_list_size--;
+	}
+}
+
 /*
  * Opal message notifier based on message type. Allow subscribers to get
  * notified for specific messgae type.
@@ -244,14 +293,30 @@ machine_early_initcall(powernv, opal_register_exception_handlers);
 int opal_message_notifier_register(enum opal_msg_type msg_type,
 					struct notifier_block *nb)
 {
+	int ret;
+	unsigned long flags;
+
 	if (!nb || msg_type >= OPAL_MSG_TYPE_MAX) {
 		pr_warn("%s: Invalid arguments, msg_type:%d\n",
 			__func__, msg_type);
 		return -EINVAL;
 	}
 
-	return atomic_notifier_chain_register(
-				&opal_msg_notifier_head[msg_type], nb);
+	spin_lock_irqsave(&msg_list_lock, flags);
+	ret = atomic_notifier_chain_register(
+		&opal_msg_notifier_head[msg_type], nb);
+
+	/*
+	 * If the registration succeeded, replay any queued messages that came
+	 * in prior to the notifier chain registration. msg_list_lock held here
+	 * to ensure they're delivered prior to any subsequent messages.
+	 */
+	if (ret == 0)
+		dequeue_replay_msg(msg_type);
+
+	spin_unlock_irqrestore(&msg_list_lock, flags);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(opal_message_notifier_register);
 
@@ -265,6 +330,23 @@ EXPORT_SYMBOL_GPL(opal_message_notifier_unregister);
 
 static void opal_message_do_notify(uint32_t msg_type, void *msg)
 {
+	unsigned long flags;
+	bool queued = false;
+
+	spin_lock_irqsave(&msg_list_lock, flags);
+	if (opal_msg_notifier_head[msg_type].head == NULL) {
+		/*
+		 * Queue up the msg since no notifiers have registered
+		 * yet for this msg_type.
+		 */
+		queue_replay_msg(msg);
+		queued = true;
+	}
+	spin_unlock_irqrestore(&msg_list_lock, flags);
+
+	if (queued)
+		return;
+
 	/* notify subscribers */
 	atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type],
 					msg_type, msg);
@@ -1002,6 +1084,9 @@ static int __init opal_init(void)
 	/* Initialise OPAL Power control interface */
 	opal_power_control_init();
 
+	/* Initialize OPAL secure variables */
+	opal_pdev_init("ibm,secvar-backend");
+
 	return 0;
 }
 machine_subsys_initcall(powernv, opal_init);