4 files changed, 61 insertions, 4 deletions

diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 2db42b18f53..8517c3c3eb3 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -436,7 +436,7 @@ __und_usr:
 	usr_entry
 
 	tst	r3, #PSR_T_BIT			@ Thumb mode?
-	bne	fpundefinstr			@ ignore FP
+	bne	__und_usr_unknown		@ ignore FP
 	sub	r4, r2, #4
 
 	@
@@ -448,7 +448,7 @@ __und_usr:
 	@
 1:	ldrt	r0, [r4]
 	adr	r9, ret_from_exception
-	adr	lr, fpundefinstr
+	adr	lr, __und_usr_unknown
 	@
 	@ fallthrough to call_fpe
 	@
@@ -476,7 +476,9 @@ __und_usr:
  * Emulators may wish to make use of the following registers:
  *  r0  = instruction opcode.
  *  r2  = PC+4
+ *  r9  = normal "successful" return address
  *  r10 = this threads thread_info structure.
+ *  lr  = unrecognised instruction return address
  */
 call_fpe:
 	tst	r0, #0x08000000			@ only CDP/CPRT/LDC/STC have bit 27
@@ -545,10 +547,12 @@ do_fpe:
 
 	.data
 ENTRY(fp_enter)
-	.word	fpundefinstr
+	.word	no_fp
 	.text
 
-fpundefinstr:
+no_fp:	mov	pc, lr
+
+__und_usr_unknown:
 	mov	r0, sp
 	adr	lr, ret_from_exception
 	b	do_undefinstr
diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c
index 6ff5e3ff6cb..3c8cdcfe8d4 100644
--- a/arch/arm/kernel/time.c
+++ b/arch/arm/kernel/time.c
@@ -29,6 +29,8 @@
 #include <linux/timer.h>
 #include <linux/irq.h>
 
+#include <linux/mc146818rtc.h>
+
 #include <asm/leds.h>
 #include <asm/thread_info.h>
 #include <asm/mach/time.h>
@@ -85,6 +87,17 @@ unsigned long long __attribute__((weak)) sched_clock(void)
 	return (unsigned long long)jiffies * (1000000000 / HZ);
 }
 
+/*
+ * An implementation of printk_clock() independent from
+ * sched_clock().  This avoids non-bootable kernels when
+ * printk_clock is enabled.
+ */
+unsigned long long printk_clock(void)
+{
+	return (unsigned long long)(jiffies - INITIAL_JIFFIES) *
+			(1000000000 / HZ);
+}
+
 static unsigned long next_rtc_update;
 
 /*
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 042a12982e9..908915675ed 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -27,6 +27,7 @@
 #include <asm/uaccess.h>
 #include <asm/unistd.h>
 #include <asm/traps.h>
+#include <asm/io.h>
 
 #include "ptrace.h"
 #include "signal.h"
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index 628348c9f6c..9df507d36e0 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -202,3 +202,42 @@ void flush_dcache_page(struct page *page)
 	}
 }
 EXPORT_SYMBOL(flush_dcache_page);
+
+/*
+ * Flush an anonymous page so that users of get_user_pages()
+ * can safely access the data.  The expected sequence is:
+ *
+ *  get_user_pages()
+ *    -> flush_anon_page
+ *  memcpy() to/from page
+ *  if written to page, flush_dcache_page()
+ */
+void __flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
+{
+	unsigned long pfn;
+
+	/* VIPT non-aliasing caches need do nothing */
+	if (cache_is_vipt_nonaliasing())
+		return;
+
+	/*
+	 * Write back and invalidate userspace mapping.
+	 */
+	pfn = page_to_pfn(page);
+	if (cache_is_vivt()) {
+		flush_cache_page(vma, vmaddr, pfn);
+	} else {
+		/*
+		 * For aliasing VIPT, we can flush an alias of the
+		 * userspace address only.
+		 */
+		flush_pfn_alias(pfn, vmaddr);
+	}
+
+	/*
+	 * Invalidate kernel mapping.  No data should be contained
+	 * in this mapping of the page.  FIXME: this is overkill
+	 * since we actually ask for a write-back and invalidate.
+	 */
+	__cpuc_flush_dcache_page(page_address(page));
+}