Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 4e6299e..ec801d3 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -40,6 +40,7 @@
 #include <asm/stacktrace.h>
 #include <asm/switch_to.h>
 #include <asm/runtime_instr.h>
+#include <asm/unwind.h>
 #include "entry.h"
 
 asmlinkage void ret_from_fork(void) asm ("ret_from_fork");
@@ -79,8 +80,8 @@
 	return 0;
 }
 
-int copy_thread_tls(unsigned long clone_flags, unsigned long new_stackp,
-		    unsigned long arg, struct task_struct *p, unsigned long tls)
+int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
+		unsigned long arg, struct task_struct *p, unsigned long tls)
 {
 	struct fake_frame
 	{
@@ -159,29 +160,10 @@
 	asm volatile("sfpc %0" : : "d" (0));
 }
 
-/*
- * fill in the FPU structure for a core dump.
- */
-int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
-{
-	save_fpu_regs();
-	fpregs->fpc = current->thread.fpu.fpc;
-	fpregs->pad = 0;
-	if (MACHINE_HAS_VX)
-		convert_vx_to_fp((freg_t *)&fpregs->fprs,
-				 current->thread.fpu.vxrs);
-	else
-		memcpy(&fpregs->fprs, current->thread.fpu.fprs,
-		       sizeof(fpregs->fprs));
-	return 1;
-}
-EXPORT_SYMBOL(dump_fpu);
-
 unsigned long get_wchan(struct task_struct *p)
 {
-	struct stack_frame *sf, *low, *high;
-	unsigned long return_address;
-	int count;
+	struct unwind_state state;
+	unsigned long ip = 0;
 
 	if (!p || p == current || p->state == TASK_RUNNING || !task_stack_page(p))
 		return 0;
@@ -189,26 +171,22 @@
 	if (!try_get_task_stack(p))
 		return 0;
 
-	low = task_stack_page(p);
-	high = (struct stack_frame *) task_pt_regs(p);
-	sf = (struct stack_frame *) p->thread.ksp;
-	if (sf <= low || sf > high) {
-		return_address = 0;
-		goto out;
-	}
-	for (count = 0; count < 16; count++) {
-		sf = (struct stack_frame *)READ_ONCE_NOCHECK(sf->back_chain);
-		if (sf <= low || sf > high) {
-			return_address = 0;
-			goto out;
+	unwind_for_each_frame(&state, p, NULL, 0) {
+		if (state.stack_info.type != STACK_TYPE_TASK) {
+			ip = 0;
+			break;
 		}
-		return_address = READ_ONCE_NOCHECK(sf->gprs[8]);
-		if (!in_sched_functions(return_address))
-			goto out;
+
+		ip = unwind_get_return_address(&state);
+		if (!ip)
+			break;
+
+		if (!in_sched_functions(ip))
+			break;
 	}
-out:
+
 	put_task_stack(p);
-	return return_address;
+	return ip;
 }
 
 unsigned long arch_align_stack(unsigned long sp)