4 files changed, 33 insertions, 18 deletions

diff --git a/arch/arm/kernel/early_printk.c b/arch/arm/kernel/early_printk.c
index 85aa2b292692..43076536965c 100644
--- a/arch/arm/kernel/early_printk.c
+++ b/arch/arm/kernel/early_printk.c
@@ -29,28 +29,17 @@ static void early_console_write(struct console *con, const char *s, unsigned n)
 	early_write(s, n);
 }
 
-static struct console early_console = {
+static struct console early_console_dev = {
 	.name =		"earlycon",
 	.write =	early_console_write,
 	.flags =	CON_PRINTBUFFER | CON_BOOT,
 	.index =	-1,
 };
 
-asmlinkage void early_printk(const char *fmt, ...)
-{
-	char buf[512];
-	int n;
-	va_list ap;
-
-	va_start(ap, fmt);
-	n = vscnprintf(buf, sizeof(buf), fmt, ap);
-	early_write(buf, n);
-	va_end(ap);
-}
-
 static int __init setup_early_printk(char *buf)
 {
-	register_console(&early_console);
+	early_console = &early_console_dev;
+	register_console(&early_console_dev);
 	return 0;
 }
 
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index ecebb893f1e7..e1286fb056f4 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -435,7 +435,7 @@ armpmu_reserve_hardware(struct arm_pmu *armpmu)
 		}
 
 		err = request_irq(irq, handle_irq,
-				  IRQF_DISABLED | IRQF_NOBALANCING,
+				  IRQF_NOBALANCING | IRQF_NO_THREAD,
 				  "arm-pmu", armpmu);
 		if (err) {
 			pr_err("unable to request IRQ%d for ARM PMU counters\n",
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 3d0c6fb74ae4..75227b36c234 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -214,9 +214,7 @@ void cpu_idle(void)
 		}
 		leds_event(led_idle_end);
 		tick_nohz_restart_sched_tick();
-		preempt_enable_no_resched();
-		schedule();
-		preempt_disable();
+		schedule_preempt_disabled();
 	}
 }
 
@@ -491,6 +489,31 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)
 }
 
 #ifdef CONFIG_MMU
+
+/*
+ * CONFIG_SPLIT_PTLOCK_CPUS results in a page->ptl lock.  If the lock is not
+ * initialized by pgtable_page_ctor() then a coredump of the vector page will
+ * fail.
+ */
+static int __init vectors_user_mapping_init_page(void)
+{
+	struct page *page;
+	unsigned long addr = 0xffff0000;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	pgd = pgd_offset_k(addr);
+	pud = pud_offset(pgd, addr);
+	pmd = pmd_offset(pud, addr);
+	page = pmd_page(*(pmd));
+
+	pgtable_page_ctor(page);
+
+	return 0;
+}
+late_initcall(vectors_user_mapping_init_page);
+
 /*
  * The vectors page is always readable from user space for the
  * atomic helpers and the signal restart code.  Let's declare a mapping
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 9e617bd4a146..c7001bc72eb0 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -672,6 +672,9 @@ static void do_signal(struct pt_regs *regs, int syscall)
 	if (!user_mode(regs))
 		return;
 
+	local_irq_enable();
+	preempt_check_resched();
+
 	/*
 	 * If we were from a system call, check for system call restarting...
 	 */