Patch "ARM: fix PTRACE_SETVFPREGS on SMP systems" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

ARM: fix PTRACE_SETVFPREGS on SMP systems

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
arm-fix-ptrace_setvfpregs-on-smp-systems.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Russell King <[email protected]>
Date: Mon, 30 May 2016 23:14:56 +0100
Subject: ARM: fix PTRACE_SETVFPREGS on SMP systems

From: Russell King <[email protected]>

commit e2dfb4b880146bfd4b6aa8e138c0205407cebbaf upstream.

PTRACE_SETVFPREGS fails to properly mark the VFP register set to be reloaded, because it undoes one of the effects of vfp_flush_hwstate().

Specifically vfp_flush_hwstate() sets thread->vfpstate.hard.cpu to an invalid CPU number, but vfp_set() overwrites this with the original CPU number, thereby rendering the hardware state as apparently "valid", even though the software state is more recent.

Fix this by reverting the previous change.

---
 arch/arm/kernel/ptrace.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -733,8 +733,8 @@ static int vfp_set(struct task_struct *t
 	if (ret)
 		return ret;
 
-	vfp_flush_hwstate(thread);
 	thread->vfpstate.hard = new_vfp;
+	vfp_flush_hwstate(thread);
 
 	return 0;
 }

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/arm-fix-ptrace_setvfpregs-on-smp-systems.patch