Upgrade to 4.4.50-rt62

The current kernel is based on rt kernel v4.4.6-rt14. We will upgrade it
to 4.4.50-rt62.
The command to achieve it is:
a) Clone a git repo from
git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git

b) Get the diff between this two changesets:
git diff 640eca2901f3435e616157b11379d3223a44b391
705619beeea1b0b48219a683fd1a901a86fdaf5e

where the two commits are:
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
640eca2901f3435e616157b11379d3223a44b391
640eca2901f3 v4.4.6-rt14
localversion-rt
[yjiang5@jnakajim-build linux-stable-rt]$ git show --oneline --name-only
705619beeea1b0b48219a683fd1a901a86fdaf5e
705619beeea1 Linux 4.4.50-rt62
localversion-rt

c) One patch has been backported thus revert the patch before applying.

 filterdiff -p1 -x scripts/package/Makefile
~/tmp/v4.4.6-rt14-4.4.50-rt62.diff  |patch -p1 --dry-run

Upstream status: backport

Change-Id: I244d57a32f6066e5a5b9915f9fbf99e7bbca6e01
Signed-off-by: Yunhong Jiang <yunhong.jiang@linux.intel.com>

4 files changed, 16 insertions, 7 deletions

diff --git a/kernel/arch/avr32/include/asm/uaccess.h b/kernel/arch/avr32/include/asm/uaccess.h
index 68cf638fa..b1ec1fa06 100644
--- a/kernel/arch/avr32/include/asm/uaccess.h
+++ b/kernel/arch/avr32/include/asm/uaccess.h
@@ -74,7 +74,7 @@ extern __kernel_size_t __copy_user(void *to, const void *from,
 
 extern __kernel_size_t copy_to_user(void __user *to, const void *from,
 				    __kernel_size_t n);
-extern __kernel_size_t copy_from_user(void *to, const void __user *from,
+extern __kernel_size_t ___copy_from_user(void *to, const void __user *from,
 				      __kernel_size_t n);
 
 static inline __kernel_size_t __copy_to_user(void __user *to, const void *from,
@@ -88,6 +88,15 @@ static inline __kernel_size_t __copy_from_user(void *to,
 {
 	return __copy_user(to, (const void __force *)from, n);
 }
+static inline __kernel_size_t copy_from_user(void *to,
+					       const void __user *from,
+					       __kernel_size_t n)
+{
+	size_t res = ___copy_from_user(to, from, n);
+	if (unlikely(res))
+		memset(to + (n - res), 0, res);
+	return res;
+}
 
 #define __copy_to_user_inatomic __copy_to_user
 #define __copy_from_user_inatomic __copy_from_user
diff --git a/kernel/arch/avr32/kernel/avr32_ksyms.c b/kernel/arch/avr32/kernel/avr32_ksyms.c
index d93ead02d..7c6cf14f0 100644
--- a/kernel/arch/avr32/kernel/avr32_ksyms.c
+++ b/kernel/arch/avr32/kernel/avr32_ksyms.c
@@ -36,7 +36,7 @@ EXPORT_SYMBOL(copy_page);
 /*
  * Userspace access stuff.
  */
-EXPORT_SYMBOL(copy_from_user);
+EXPORT_SYMBOL(___copy_from_user);
 EXPORT_SYMBOL(copy_to_user);
 EXPORT_SYMBOL(__copy_user);
 EXPORT_SYMBOL(strncpy_from_user);
diff --git a/kernel/arch/avr32/lib/copy_user.S b/kernel/arch/avr32/lib/copy_user.S
index ea59c04b0..075373471 100644
--- a/kernel/arch/avr32/lib/copy_user.S
+++ b/kernel/arch/avr32/lib/copy_user.S
@@ -23,13 +23,13 @@
 	 */
 	.text
 	.align	1
-	.global	copy_from_user
-	.type	copy_from_user, @function
-copy_from_user:
+	.global	___copy_from_user
+	.type	___copy_from_user, @function
+___copy_from_user:
 	branch_if_kernel r8, __copy_user
 	ret_if_privileged r8, r11, r10, r10
 	rjmp	__copy_user
-	.size	copy_from_user, . - copy_from_user
+	.size	___copy_from_user, . - ___copy_from_user
 
 	.global	copy_to_user
 	.type	copy_to_user, @function
diff --git a/kernel/arch/avr32/mach-at32ap/pio.c b/kernel/arch/avr32/mach-at32ap/pio.c
index 4f61378c3..456128174 100644
--- a/kernel/arch/avr32/mach-at32ap/pio.c
+++ b/kernel/arch/avr32/mach-at32ap/pio.c
@@ -435,7 +435,7 @@ void __init at32_init_pio(struct platform_device *pdev)
 	struct resource *regs;
 	struct pio_device *pio;
 
-	if (pdev->id > MAX_NR_PIO_DEVICES) {
+	if (pdev->id >= MAX_NR_PIO_DEVICES) {
 		dev_err(&pdev->dev, "only %d PIO devices supported\n",
 			MAX_NR_PIO_DEVICES);
 		return;