Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index d4f7fd4..339870e 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -371,7 +371,7 @@
 static int get_frame_info(struct mips_frame_info *info)
 {
 	bool is_mmips = IS_ENABLED(CONFIG_CPU_MICROMIPS);
-	union mips_instruction insn, *ip, *ip_end;
+	union mips_instruction insn, *ip;
 	const unsigned int max_insns = 128;
 	unsigned int last_insn_size = 0;
 	unsigned int i;
@@ -384,10 +384,9 @@
 	if (!ip)
 		goto err;
 
-	ip_end = (void *)ip + info->func_size;
-
-	for (i = 0; i < max_insns && ip < ip_end; i++) {
+	for (i = 0; i < max_insns; i++) {
 		ip = (void *)ip + last_insn_size;
+
 		if (is_mmips && mm_insn_16bit(ip->halfword[0])) {
 			insn.word = ip->halfword[0] << 16;
 			last_insn_size = 2;
@@ -737,10 +736,9 @@
 	/*
 	 * This is icky, but we use this to simply ensure that all CPUs have
 	 * context switched, regardless of whether they were previously running
-	 * kernel or user code. This ensures that no CPU currently has its FPU
-	 * enabled, or is about to attempt to enable it through any path other
-	 * than enable_restore_fp_context() which will wait appropriately for
-	 * fp_mode_switching to be zero.
+	 * kernel or user code. This ensures that no CPU that a mode-switching
+	 * program may execute on keeps its FPU enabled (& in the old mode)
+	 * throughout the mode switch.
 	 */
 	return 0;
 }
@@ -829,8 +827,6 @@
 		work_on_cpu(cpu, prepare_for_fp_mode_switch, NULL);
 	put_online_cpus();
 
-	wake_up_var(&task->mm->context.fp_mode_switching);
-
 	return 0;
 }