FAILED: patch "[PATCH] powerpc/tm: Fix clearing MSR[TS] in current when reclaiming" failed to apply to 4.14-stable tree

index e6c30cee6abf..d215f9554553 100644
@@ -200,14 +200,27 @@ unsigned long get_tm_stackpointer(struct task_struct *tsk)
 	 * normal/non-checkpointed stack pointer.
 	 */
 
+	unsigned long ret = tsk->thread.regs->gpr[1];
+
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	BUG_ON(tsk != current);
 
 	if (MSR_TM_ACTIVE(tsk->thread.regs->msr)) {
+		preempt_disable();
 		tm_reclaim_current(TM_CAUSE_SIGNAL);
 		if (MSR_TM_TRANSACTIONAL(tsk->thread.regs->msr))
-			return tsk->thread.ckpt_regs.gpr[1];
+			ret = tsk->thread.ckpt_regs.gpr[1];
+
+		/*
+		 * If we treclaim, we must clear the current thread's TM bits
+		 * before re-enabling preemption. Otherwise we might be
+		 * preempted and have the live MSR[TS] changed behind our back
+		 * (tm_recheckpoint_new_task() would recheckpoint). Besides, we
+		 * enter the signal handler in non-transactional state.
+		 */
+		tsk->thread.regs->msr &= ~MSR_TS_MASK;
+		preempt_enable();
 	}
 #endif
-	return tsk->thread.regs->gpr[1];
+	return ret;
 }

index 98600b276f76..1b090a76b444 100644
@@ -489,19 +489,11 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
  */
 static int save_tm_user_regs(struct pt_regs *regs,
 			     struct mcontext __user *frame,
-			     struct mcontext __user *tm_frame, int sigret)
+			     struct mcontext __user *tm_frame, int sigret,
+			     unsigned long msr)
 {
-	unsigned long msr = regs->msr;
-
 	WARN_ON(tm_suspend_disabled);
 
-	/* Remove TM bits from thread's MSR.  The MSR in the sigcontext
-	 * just indicates to userland that we were doing a transaction, but we
-	 * don't want to return in transactional state.  This also ensures
-	 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
-	 */
-	regs->msr &= ~MSR_TS_MASK;
-
 	/* Save both sets of general registers */
 	if (save_general_regs(&current->thread.ckpt_regs, frame)
 	    || save_general_regs(regs, tm_frame))

@@ -912,6 +904,10 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
 	int sigret;
 	unsigned long tramp;
 	struct pt_regs *regs = tsk->thread.regs;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	/* Save the thread's msr before get_tm_stackpointer() changes it */
+	unsigned long msr = regs->msr;
+#endif
 
 	BUG_ON(tsk != current);
 

@@ -944,13 +940,13 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	tm_frame = &rt_sf->uc_transact.uc_mcontext;
-	if (MSR_TM_ACTIVE(regs->msr)) {
+	if (MSR_TM_ACTIVE(msr)) {
 		if (__put_user((unsigned long)&rt_sf->uc_transact,
 			       &rt_sf->uc.uc_link) ||
 		    __put_user((unsigned long)tm_frame,
 			       &rt_sf->uc_transact.uc_regs))
 			goto badframe;
-		if (save_tm_user_regs(regs, frame, tm_frame, sigret))
+		if (save_tm_user_regs(regs, frame, tm_frame, sigret, msr))
 			goto badframe;
 	}
 	else

@@ -1369,6 +1365,10 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
 	int sigret;
 	unsigned long tramp;
 	struct pt_regs *regs = tsk->thread.regs;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	/* Save the thread's msr before get_tm_stackpointer() changes it */
+	unsigned long msr = regs->msr;
+#endif
 
 	BUG_ON(tsk != current);
 

@@ -1402,9 +1402,9 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	tm_mctx = &frame->mctx_transact;
-	if (MSR_TM_ACTIVE(regs->msr)) {
+	if (MSR_TM_ACTIVE(msr)) {
 		if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
-				      sigret))
+				      sigret, msr))
 			goto badframe;
 	}
 	else

index 117515564ec7..84ed2e77ef9c 100644
@@ -192,7 +192,8 @@ static long setup_sigcontext(struct sigcontext __user *sc,
 static long setup_tm_sigcontexts(struct sigcontext __user *sc,
 				 struct sigcontext __user *tm_sc,
 				 struct task_struct *tsk,
-				 int signr, sigset_t *set, unsigned long handler)
+				 int signr, sigset_t *set, unsigned long handler,
+				 unsigned long msr)
 {
 	/* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
 	 * process never used altivec yet (MSR_VEC is zero in pt_regs of

@@ -207,12 +208,11 @@ static long setup_tm_sigcontexts(struct sigcontext __user *sc,
 	elf_vrreg_t __user *tm_v_regs = sigcontext_vmx_regs(tm_sc);
 #endif
 	struct pt_regs *regs = tsk->thread.regs;
-	unsigned long msr = tsk->thread.regs->msr;
 	long err = 0;
 
 	BUG_ON(tsk != current);
 
-	BUG_ON(!MSR_TM_ACTIVE(regs->msr));
+	BUG_ON(!MSR_TM_ACTIVE(msr));
 
 	WARN_ON(tm_suspend_disabled);
 

@@ -222,13 +222,6 @@ static long setup_tm_sigcontexts(struct sigcontext __user *sc,
 	 */
 	msr |= tsk->thread.ckpt_regs.msr & (MSR_FP | MSR_VEC | MSR_VSX);
 
-	/* Remove TM bits from thread's MSR.  The MSR in the sigcontext
-	 * just indicates to userland that we were doing a transaction, but we
-	 * don't want to return in transactional state.  This also ensures
-	 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
-	 */
-	regs->msr &= ~MSR_TS_MASK;
-
 #ifdef CONFIG_ALTIVEC
 	err |= __put_user(v_regs, &sc->v_regs);
 	err |= __put_user(tm_v_regs, &tm_sc->v_regs);

@@ -824,6 +817,10 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
 	unsigned long newsp = 0;
 	long err = 0;
 	struct pt_regs *regs = tsk->thread.regs;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	/* Save the thread's msr before get_tm_stackpointer() changes it */
+	unsigned long msr = regs->msr;
+#endif
 
 	BUG_ON(tsk != current);
 

@@ -841,7 +838,7 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
 	err |= __put_user(0, &frame->uc.uc_flags);
 	err |= __save_altstack(&frame->uc.uc_stack, regs->gpr[1]);
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-	if (MSR_TM_ACTIVE(regs->msr)) {
+	if (MSR_TM_ACTIVE(msr)) {
 		/* The ucontext_t passed to userland points to the second
 		 * ucontext_t (for transactional state) with its uc_link ptr.
 		 */

@@ -849,7 +846,8 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
 		err |= setup_tm_sigcontexts(&frame->uc.uc_mcontext,
 					    &frame->uc_transact.uc_mcontext,
 					    tsk, ksig->sig, NULL,
-					    (unsigned long)ksig->ka.sa.sa_handler);
+					    (unsigned long)ksig->ka.sa.sa_handler,
+					    msr);
 	} else
 #endif
 	{