LoongArch: uprobes: Remove redundant code about resume_era

arch_uprobe_skip_sstep() returns true if instruction was emulated, that
is to say, there is no need to single step for the emulated instructions.
regs->csr_era will point to the destination address directly after the
exception, so the resume_era related code is redundant, just remove them.

Cc: stable@vger.kernel.org
Fixes: 19bc6cb ("LoongArch: Add uprobes support")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Author: seehearfeel

arch/loongarch/include/asm/uprobes.h

@@ -15,7 +15,6 @@ typedef u32 uprobe_opcode_t;
 #define UPROBE_XOLBP_INSN	__emit_break(BRK_UPROBE_XOLBP)
 
 struct arch_uprobe {
-	unsigned long	resume_era;
 	u32	insn[2];
 	u32	ixol[2];
 	bool	simulate;

arch/loongarch/kernel/uprobes.c

@@ -52,11 +52,7 @@ int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
 
 	WARN_ON_ONCE(current->thread.trap_nr != UPROBE_TRAP_NR);
 	current->thread.trap_nr = utask->autask.saved_trap_nr;
-
-	if (auprobe->simulate)
-		instruction_pointer_set(regs, auprobe->resume_era);
-	else
-		instruction_pointer_set(regs, utask->vaddr + LOONGARCH_INSN_SIZE);
+	instruction_pointer_set(regs, utask->vaddr + LOONGARCH_INSN_SIZE);
 
 	return 0;
 }
@@ -86,7 +82,6 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs)
 
 	insn.word = auprobe->insn[0];
 	arch_simulate_insn(insn, regs);
-	auprobe->resume_era = regs->csr_era;
 
 	return true;
 }