1 files changed, 50 insertions, 33 deletions

diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index d7e288f3a1e7..af4c862ec5ff 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -9,50 +9,35 @@
  * Copyright (C) 2004 Thiemo Seufer
  * Copyright (C) 2013  Imagination Technologies Ltd.
  */
+#include <linux/cpu.h>
 #include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/sched/debug.h>
-#include <linux/sched/task.h>
-#include <linux/sched/task_stack.h>
-#include <linux/tick.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/stddef.h>
-#include <linux/unistd.h>
-#include <linux/export.h>
-#include <linux/ptrace.h>
-#include <linux/mman.h>
-#include <linux/personality.h>
-#include <linux/sys.h>
 #include <linux/init.h>
-#include <linux/completion.h>
 #include <linux/kallsyms.h>
-#include <linux/random.h>
-#include <linux/prctl.h>
+#include <linux/kernel.h>
 #include <linux/nmi.h>
-#include <linux/cpu.h>
+#include <linux/personality.h>
+#include <linux/prctl.h>
+#include <linux/random.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task_stack.h>
 
 #include <asm/abi.h>
 #include <asm/asm.h>
-#include <asm/bootinfo.h>
-#include <asm/cpu.h>
 #include <asm/dsemul.h>
 #include <asm/dsp.h>
+#include <asm/exec.h>
 #include <asm/fpu.h>
+#include <asm/inst.h>
 #include <asm/irq.h>
-#include <asm/mips-cps.h>
+#include <asm/irq_regs.h>
+#include <asm/isadep.h>
 #include <asm/msa.h>
+#include <asm/mips-cps.h>
 #include <asm/mipsregs.h>
 #include <asm/processor.h>
 #include <asm/reg.h>
-#include <linux/uaccess.h>
-#include <asm/io.h>
-#include <asm/elf.h>
-#include <asm/isadep.h>
-#include <asm/inst.h>
 #include <asm/stacktrace.h>
-#include <asm/irq_regs.h>
-#include <asm/exec.h>
 
 #ifdef CONFIG_HOTPLUG_CPU
 void arch_cpu_idle_dead(void)
@@ -205,6 +190,36 @@ struct mips_frame_info {
 #define J_TARGET(pc,target)	\
 		(((unsigned long)(pc) & 0xf0000000) | ((target) << 2))
 
+static inline int is_jr_ra_ins(union mips_instruction *ip)
+{
+#ifdef CONFIG_CPU_MICROMIPS
+	/*
+	 * jr16 ra
+	 * jr ra
+	 */
+	if (mm_insn_16bit(ip->word >> 16)) {
+		if (ip->mm16_r5_format.opcode == mm_pool16c_op &&
+		    ip->mm16_r5_format.rt == mm_jr16_op &&
+		    ip->mm16_r5_format.imm == 31)
+			return 1;
+		return 0;
+	}
+
+	if (ip->r_format.opcode == mm_pool32a_op &&
+	    ip->r_format.func == mm_pool32axf_op &&
+	    ((ip->u_format.uimmediate >> 6) & GENMASK(9, 0)) == mm_jalr_op &&
+	    ip->r_format.rt == 31)
+		return 1;
+	return 0;
+#else
+	if (ip->r_format.opcode == spec_op &&
+	    ip->r_format.func == jr_op &&
+	    ip->r_format.rs == 31)
+		return 1;
+	return 0;
+#endif
+}
+
 static inline int is_ra_save_ins(union mips_instruction *ip, int *poff)
 {
 #ifdef CONFIG_CPU_MICROMIPS
@@ -390,10 +405,8 @@ static inline int is_sp_move_ins(union mips_instruction *ip, int *frame_size)
 static int get_frame_info(struct mips_frame_info *info)
 {
 	bool is_mmips = IS_ENABLED(CONFIG_CPU_MICROMIPS);
-	union mips_instruction insn, *ip;
-	const unsigned int max_insns = 128;
+	union mips_instruction insn, *ip, *ip_end;
 	unsigned int last_insn_size = 0;
-	unsigned int i;
 	bool saw_jump = false;
 
 	info->pc_offset = -1;
@@ -403,7 +416,9 @@ static int get_frame_info(struct mips_frame_info *info)
 	if (!ip)
 		goto err;
 
-	for (i = 0; i < max_insns; i++) {
+	ip_end = (void *)ip + (info->func_size ? info->func_size : 512);
+
+	while (ip < ip_end) {
 		ip = (void *)ip + last_insn_size;
 
 		if (is_mmips && mm_insn_16bit(ip->halfword[0])) {
@@ -417,7 +432,9 @@ static int get_frame_info(struct mips_frame_info *info)
 			last_insn_size = 4;
 		}
 
-		if (!info->frame_size) {
+		if (is_jr_ra_ins(ip)) {
+			break;
+		} else if (!info->frame_size) {
 			is_sp_move_ins(&insn, &info->frame_size);
 			continue;
 		} else if (!saw_jump && is_jump_ins(ip)) {