Merge tag 's390-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Vasily Gorbik:

 - Fix a couple of late pt_regs flags handling findings of conversion to
   generic entry.

 - Fix potential register clobbering in stack switch helper.

 - Fix thread/group masks for offline cpus.

 - Fix cleanup of mdev resources when remove callback is invoked in
   vfio-ap code.

* tag 's390-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/stack: fix possible register corruption with stack switch helper
  s390/topology: clear thread/group maps for offline cpus
  s390/vfio-ap: clean up mdev resources when remove callback invoked
  s390: clear pt_regs::flags on irq entry
  s390: fix system call restart with multiple signals

4 files changed, 21 insertions, 11 deletions

diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h
index 2b543163d90a..76c6034428be 100644
--- a/arch/s390/include/asm/stacktrace.h
+++ b/arch/s390/include/asm/stacktrace.h
@@ -91,12 +91,16 @@ struct stack_frame {
 	CALL_ARGS_4(arg1, arg2, arg3, arg4);				\
 	register unsigned long r4 asm("6") = (unsigned long)(arg5)
 
-#define CALL_FMT_0 "=&d" (r2) :
-#define CALL_FMT_1 "+&d" (r2) :
-#define CALL_FMT_2 CALL_FMT_1 "d" (r3),
-#define CALL_FMT_3 CALL_FMT_2 "d" (r4),
-#define CALL_FMT_4 CALL_FMT_3 "d" (r5),
-#define CALL_FMT_5 CALL_FMT_4 "d" (r6),
+/*
+ * To keep this simple mark register 2-6 as being changed (volatile)
+ * by the called function, even though register 6 is saved/nonvolatile.
+ */
+#define CALL_FMT_0 "=&d" (r2)
+#define CALL_FMT_1 "+&d" (r2)
+#define CALL_FMT_2 CALL_FMT_1, "+&d" (r3)
+#define CALL_FMT_3 CALL_FMT_2, "+&d" (r4)
+#define CALL_FMT_4 CALL_FMT_3, "+&d" (r5)
+#define CALL_FMT_5 CALL_FMT_4, "+&d" (r6)
 
 #define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory"
 #define CALL_CLOBBER_4 CALL_CLOBBER_5
@@ -118,7 +122,7 @@ struct stack_frame {
 		"	brasl	14,%[_fn]\n"				\
 		"	la	15,0(%[_prev])\n"			\
 		: [_prev] "=&a" (prev), CALL_FMT_##nr			\
-		  [_stack] "R" (stack),					\
+		: [_stack] "R" (stack),					\
 		  [_bc] "i" (offsetof(struct stack_frame, back_chain)),	\
 		  [_frame] "d" (frame),					\
 		  [_fn] "X" (fn) : CALL_CLOBBER_##nr);			\
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 9cc71ca9a88f..e84f495e7eb2 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -418,6 +418,7 @@ ENTRY(\name)
 	xgr	%r6,%r6
 	xgr	%r7,%r7
 	xgr	%r10,%r10
+	xc	__PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
 	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
 	stmg	%r8,%r9,__PT_PSW(%r11)
 	tm	%r8,0x0001		# coming from user space?
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 90163e6184f5..080e7aed181f 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -512,7 +512,6 @@ void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal)
 
 	/* No handlers present - check for system call restart */
 	clear_pt_regs_flag(regs, PIF_SYSCALL);
-	clear_pt_regs_flag(regs, PIF_SYSCALL_RESTART);
 	if (current->thread.system_call) {
 		regs->int_code = current->thread.system_call;
 		switch (regs->gprs[2]) {
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index bfcc327acc6b..26aa2614ee35 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -66,7 +66,10 @@ static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int c
 {
 	static cpumask_t mask;
 
-	cpumask_copy(&mask, cpumask_of(cpu));
+	cpumask_clear(&mask);
+	if (!cpu_online(cpu))
+		goto out;
+	cpumask_set_cpu(cpu, &mask);
 	switch (topology_mode) {
 	case TOPOLOGY_MODE_HW:
 		while (info) {
@@ -83,10 +86,10 @@ static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int c
 	default:
 		fallthrough;
 	case TOPOLOGY_MODE_SINGLE:
-		cpumask_copy(&mask, cpumask_of(cpu));
 		break;
 	}
 	cpumask_and(&mask, &mask, cpu_online_mask);
+out:
 	cpumask_copy(dst, &mask);
 }
 
@@ -95,7 +98,10 @@ static void cpu_thread_map(cpumask_t *dst, unsigned int cpu)
 	static cpumask_t mask;
 	int i;
 
-	cpumask_copy(&mask, cpumask_of(cpu));
+	cpumask_clear(&mask);
+	if (!cpu_online(cpu))
+		goto out;
+	cpumask_set_cpu(cpu, &mask);
 	if (topology_mode != TOPOLOGY_MODE_HW)
 		goto out;
 	cpu -= cpu % (smp_cpu_mtid + 1);