These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

1 files changed, 26 insertions, 9 deletions

diff --git a/kernel/arch/arm/lib/uaccess_with_memcpy.c b/kernel/arch/arm/lib/uaccess_with_memcpy.c
index 3e58d7100..588bbc288 100644
--- a/kernel/arch/arm/lib/uaccess_with_memcpy.c
+++ b/kernel/arch/arm/lib/uaccess_with_memcpy.c
@@ -88,6 +88,7 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp)
 static unsigned long noinline
 __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
 {
+	unsigned long ua_flags;
 	int atomic;
 
 	if (unlikely(segment_eq(get_fs(), KERNEL_DS))) {
@@ -96,7 +97,7 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
 	}
 
 	/* the mmap semaphore is taken only if not in an atomic context */
-	atomic = in_atomic();
+	atomic = faulthandler_disabled();
 
 	if (!atomic)
 		down_read(&current->mm->mmap_sem);
@@ -118,7 +119,9 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
 		if (tocopy > n)
 			tocopy = n;
 
+		ua_flags = uaccess_save_and_enable();
 		memcpy((void *)to, from, tocopy);
+		uaccess_restore(ua_flags);
 		to += tocopy;
 		from += tocopy;
 		n -= tocopy;
@@ -136,7 +139,7 @@ out:
 }
 
 unsigned long
-__copy_to_user(void __user *to, const void *from, unsigned long n)
+arm_copy_to_user(void __user *to, const void *from, unsigned long n)
 {
 	/*
 	 * This test is stubbed out of the main function above to keep
@@ -145,14 +148,21 @@ __copy_to_user(void __user *to, const void *from, unsigned long n)
 	 * With frame pointer disabled, tail call optimization kicks in
 	 * as well making this test almost invisible.
 	 */
-	if (n < 64)
-		return __copy_to_user_std(to, from, n);
-	return __copy_to_user_memcpy(to, from, n);
+	if (n < 64) {
+		unsigned long ua_flags = uaccess_save_and_enable();
+		n = __copy_to_user_std(to, from, n);
+		uaccess_restore(ua_flags);
+	} else {
+		n = __copy_to_user_memcpy(to, from, n);
+	}
+	return n;
 }
 	
 static unsigned long noinline
 __clear_user_memset(void __user *addr, unsigned long n)
 {
+	unsigned long ua_flags;
+
 	if (unlikely(segment_eq(get_fs(), KERNEL_DS))) {
 		memset((void *)addr, 0, n);
 		return 0;
@@ -175,7 +185,9 @@ __clear_user_memset(void __user *addr, unsigned long n)
 		if (tocopy > n)
 			tocopy = n;
 
+		ua_flags = uaccess_save_and_enable();
 		memset((void *)addr, 0, tocopy);
+		uaccess_restore(ua_flags);
 		addr += tocopy;
 		n -= tocopy;
 
@@ -190,12 +202,17 @@ out:
 	return n;
 }
 
-unsigned long __clear_user(void __user *addr, unsigned long n)
+unsigned long arm_clear_user(void __user *addr, unsigned long n)
 {
 	/* See rational for this in __copy_to_user() above. */
-	if (n < 64)
-		return __clear_user_std(addr, n);
-	return __clear_user_memset(addr, n);
+	if (n < 64) {
+		unsigned long ua_flags = uaccess_save_and_enable();
+		n = __clear_user_std(addr, n);
+		uaccess_restore(ua_flags);
+	} else {
+		n = __clear_user_memset(addr, n);
+	}
+	return n;
 }
 
 #if 0