From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Wed, 6 Dec 2017 07:45:02 +0000 (+0100)
Subject: 4.14-stable patches
X-Git-Tag: v3.18.87~27
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e0df803052c1d67a1f71258033da0f8f6dfe002c;p=thirdparty%2Fkernel%2Fstable-queue.git

4.14-stable patches

added patches:
	s390-runtime-instrumentation-simplify-task-exit-handling.patch
---

diff --git a/queue-4.14/s390-runtime-instrumentation-simplify-task-exit-handling.patch b/queue-4.14/s390-runtime-instrumentation-simplify-task-exit-handling.patch
new file mode 100644
index 00000000000..002edf9676b
--- /dev/null
+++ b/queue-4.14/s390-runtime-instrumentation-simplify-task-exit-handling.patch
@@ -0,0 +1,118 @@
+From 8d9047f8b967ce6181fd824ae922978e1b055cc0 Mon Sep 17 00:00:00 2001
+From: Heiko Carstens <heiko.carstens@de.ibm.com>
+Date: Mon, 11 Sep 2017 11:24:22 +0200
+Subject: s390/runtime instrumentation: simplify task exit handling
+
+From: Heiko Carstens <heiko.carstens@de.ibm.com>
+
+commit 8d9047f8b967ce6181fd824ae922978e1b055cc0 upstream.
+
+Free data structures required for runtime instrumentation from
+arch_release_task_struct(). This allows to simplify the code a bit,
+and also makes the semantics a bit easier: arch_release_task_struct()
+is never called from the task that is being removed.
+
+In addition this allows to get rid of exit_thread() in a later patch.
+
+Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
+Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
+Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/s390/include/asm/runtime_instr.h |    4 +++-
+ arch/s390/kernel/process.c            |    5 ++---
+ arch/s390/kernel/runtime_instr.c      |   30 +++++++++++++++---------------
+ 3 files changed, 20 insertions(+), 19 deletions(-)
+
+--- a/arch/s390/include/asm/runtime_instr.h
++++ b/arch/s390/include/asm/runtime_instr.h
+@@ -86,6 +86,8 @@ static inline void restore_ri_cb(struct
+ 		load_runtime_instr_cb(&runtime_instr_empty_cb);
+ }
+ 
+-void exit_thread_runtime_instr(void);
++struct task_struct;
++
++void runtime_instr_release(struct task_struct *tsk);
+ 
+ #endif /* _RUNTIME_INSTR_H */
+--- a/arch/s390/kernel/process.c
++++ b/arch/s390/kernel/process.c
+@@ -49,10 +49,8 @@ extern void kernel_thread_starter(void);
+  */
+ void exit_thread(struct task_struct *tsk)
+ {
+-	if (tsk == current) {
+-		exit_thread_runtime_instr();
++	if (tsk == current)
+ 		exit_thread_gs();
+-	}
+ }
+ 
+ void flush_thread(void)
+@@ -65,6 +63,7 @@ void release_thread(struct task_struct *
+ 
+ void arch_release_task_struct(struct task_struct *tsk)
+ {
++	runtime_instr_release(tsk);
+ }
+ 
+ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
+--- a/arch/s390/kernel/runtime_instr.c
++++ b/arch/s390/kernel/runtime_instr.c
+@@ -21,11 +21,24 @@
+ /* empty control block to disable RI by loading it */
+ struct runtime_instr_cb runtime_instr_empty_cb;
+ 
++void runtime_instr_release(struct task_struct *tsk)
++{
++	kfree(tsk->thread.ri_cb);
++}
++
+ static void disable_runtime_instr(void)
+ {
+-	struct pt_regs *regs = task_pt_regs(current);
++	struct task_struct *task = current;
++	struct pt_regs *regs;
+ 
++	if (!task->thread.ri_cb)
++		return;
++	regs = task_pt_regs(task);
++	preempt_disable();
+ 	load_runtime_instr_cb(&runtime_instr_empty_cb);
++	kfree(task->thread.ri_cb);
++	task->thread.ri_cb = NULL;
++	preempt_enable();
+ 
+ 	/*
+ 	 * Make sure the RI bit is deleted from the PSW. If the user did not
+@@ -46,19 +59,6 @@ static void init_runtime_instr_cb(struct
+ 	cb->valid = 1;
+ }
+ 
+-void exit_thread_runtime_instr(void)
+-{
+-	struct task_struct *task = current;
+-
+-	preempt_disable();
+-	if (!task->thread.ri_cb)
+-		return;
+-	disable_runtime_instr();
+-	kfree(task->thread.ri_cb);
+-	task->thread.ri_cb = NULL;
+-	preempt_enable();
+-}
+-
+ SYSCALL_DEFINE1(s390_runtime_instr, int, command)
+ {
+ 	struct runtime_instr_cb *cb;
+@@ -67,7 +67,7 @@ SYSCALL_DEFINE1(s390_runtime_instr, int,
+ 		return -EOPNOTSUPP;
+ 
+ 	if (command == S390_RUNTIME_INSTR_STOP) {
+-		exit_thread_runtime_instr();
++		disable_runtime_instr();
+ 		return 0;
+ 	}
+ 
diff --git a/queue-4.14/series b/queue-4.14/series
index 92080601028..4a807c5779a 100644
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -1,3 +1,4 @@
 drm-fsl-dcu-avoid-disabling-pixel-clock-twice-on-suspend.patch
 drm-fsl-dcu-enable-irq-before-drm_atomic_helper_resume.patch
 drm-amdgpu-use-unsigned-ring-indices-in-amdgpu_queue_mgr_map.patch
+s390-runtime-instrumentation-simplify-task-exit-handling.patch