6 files changed, 48 insertions, 17 deletions
diff --git a/arch/parisc/kernel/alternative.c b/arch/parisc/kernel/alternative.c
index 66f5672c70bd..25c4d6c3375d 100644
--- a/arch/parisc/kernel/alternative.c
+++ b/arch/parisc/kernel/alternative.c
@@ -25,7 +25,7 @@ void __init_or_module apply_alternatives(struct alt_instr *start,
 {
 	struct alt_instr *entry;
 	int index = 0, applied = 0;
-	int num_cpus = num_online_cpus();
+	int num_cpus = num_present_cpus();
 	u16 cond_check;
 
 	cond_check = ALT_COND_ALWAYS |
diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
index 1d3b8bc8a623..ca4a302d4365 100644
--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -399,6 +399,7 @@ void flush_dcache_page(struct page *page)
 	unsigned long offset;
 	unsigned long addr, old_addr = 0;
 	unsigned long count = 0;
+	unsigned long flags;
 	pgoff_t pgoff;
 
 	if (mapping && !mapping_mapped(mapping)) {
@@ -420,7 +421,7 @@ void flush_dcache_page(struct page *page)
 	 * to flush one address here for them all to become coherent
 	 * on machines that support equivalent aliasing
 	 */
-	flush_dcache_mmap_lock(mapping);
+	flush_dcache_mmap_lock_irqsave(mapping, flags);
 	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
 		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
 		addr = mpnt->vm_start + offset;
@@ -460,7 +461,7 @@ void flush_dcache_page(struct page *page)
 		}
 		WARN_ON(++count == 4096);
 	}
-	flush_dcache_mmap_unlock(mapping);
+	flush_dcache_mmap_unlock_irqrestore(mapping, flags);
 }
 EXPORT_SYMBOL(flush_dcache_page);
 
diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index ba87f791323b..71ed5391f29d 100644
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -446,11 +446,27 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr,
 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
 		enum dma_data_direction dir)
 {
+	/*
+	 * fdc: The data cache line is written back to memory, if and only if
+	 * it is dirty, and then invalidated from the data cache.
+	 */
 	flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
 }
 
 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
 		enum dma_data_direction dir)
 {
-	flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
+	unsigned long addr = (unsigned long) phys_to_virt(paddr);
+
+	switch (dir) {
+	case DMA_TO_DEVICE:
+	case DMA_BIDIRECTIONAL:
+		flush_kernel_dcache_range(addr, size);
+		return;
+	case DMA_FROM_DEVICE:
+		purge_kernel_dcache_range_asm(addr, addr + size);
+		return;
+	default:
+		BUG();
+	}
 }
diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c
index 97c6f875bd0e..abdbf038d643 100644
--- a/arch/parisc/kernel/process.c
+++ b/arch/parisc/kernel/process.c
@@ -122,13 +122,18 @@ void machine_power_off(void)
 	/* It seems we have no way to power the system off via
 	 * software. The user has to press the button himself. */
 
-	printk(KERN_EMERG "System shut down completed.\n"
-	       "Please power this system off now.");
+	printk("Power off or press RETURN to reboot.\n");
 
 	/* prevent soft lockup/stalled CPU messages for endless loop. */
 	rcu_sysrq_start();
 	lockup_detector_soft_poweroff();
-	for (;;);
+	while (1) {
+		/* reboot if user presses RETURN key */
+		if (pdc_iodc_getc() == 13) {
+			printk("Rebooting...\n");
+			machine_restart(NULL);
+		}
+	}
 }
 
 void (*pm_power_off)(void);
@@ -166,8 +171,8 @@ void __noreturn arch_cpu_idle_dead(void)
 
 	local_irq_disable();
 
-	/* Tell __cpu_die() that this CPU is now safe to dispose of. */
-	(void)cpu_report_death();
+	/* Tell the core that this CPU is now safe to dispose of. */
+	cpuhp_ap_report_dead();
 
 	/* Ensure that the cache lines are written out. */
 	flush_cache_all_local();
diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c
index b7fc859fa87d..6b6eaa485946 100644
--- a/arch/parisc/kernel/smp.c
+++ b/arch/parisc/kernel/smp.c
@@ -500,11 +500,10 @@ int __cpu_disable(void)
 void __cpu_die(unsigned int cpu)
 {
 	pdc_cpu_rendezvous_lock();
+}
 
-	if (!cpu_wait_death(cpu, 5)) {
-		pr_crit("CPU%u: cpu didn't die\n", cpu);
-		return;
-	}
+void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu)
+{
 	pr_info("CPU%u: is shutting down\n", cpu);
 
 	/* set task's state to interruptible sleep */
diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c
index f9696fbf646c..304eebd1c83e 100644
--- a/arch/parisc/kernel/traps.c
+++ b/arch/parisc/kernel/traps.c
@@ -47,6 +47,10 @@
 #include <linux/kgdb.h>
 #include <linux/kprobes.h>
 
+#if defined(CONFIG_LIGHTWEIGHT_SPINLOCK_CHECK)
+#include <asm/spinlock.h>
+#endif
+
 #include "../math-emu/math-emu.h"	/* for handle_fpe() */
 
 static void parisc_show_stack(struct task_struct *task,
@@ -291,24 +295,30 @@ static void handle_break(struct pt_regs *regs)
 	}
 
 #ifdef CONFIG_KPROBES
-	if (unlikely(iir == PARISC_KPROBES_BREAK_INSN)) {
+	if (unlikely(iir == PARISC_KPROBES_BREAK_INSN && !user_mode(regs))) {
 		parisc_kprobe_break_handler(regs);
 		return;
 	}
-	if (unlikely(iir == PARISC_KPROBES_BREAK_INSN2)) {
+	if (unlikely(iir == PARISC_KPROBES_BREAK_INSN2 && !user_mode(regs))) {
 		parisc_kprobe_ss_handler(regs);
 		return;
 	}
 #endif
 
 #ifdef CONFIG_KGDB
-	if (unlikely(iir == PARISC_KGDB_COMPILED_BREAK_INSN ||
-		iir == PARISC_KGDB_BREAK_INSN)) {
+	if (unlikely((iir == PARISC_KGDB_COMPILED_BREAK_INSN ||
+		iir == PARISC_KGDB_BREAK_INSN)) && !user_mode(regs)) {
 		kgdb_handle_exception(9, SIGTRAP, 0, regs);
 		return;
 	}
 #endif
 
+#ifdef CONFIG_LIGHTWEIGHT_SPINLOCK_CHECK
+        if ((iir == SPINLOCK_BREAK_INSN) && !user_mode(regs)) {
+		die_if_kernel("Spinlock was trashed", regs, 1);
+	}
+#endif
+
 	if (unlikely(iir != GDB_BREAK_INSN))
 		parisc_printk_ratelimited(0, regs,
 			KERN_DEBUG "break %d,%d: pid=%d command='%s'\n",