LoongArch: Make compute_return_era() return void

mainline inclusion
from mainline-v5.19-rc4
commit ea18d434
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5OHOB
CVE: NA

--------------------------------

compute_return_era() always returns 0, make it return void,
and then no need to check its return value for its callers.
Signed-off-by: NTiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: NHuacai Chen <chenhuacai@loongson.cn>

arch/loongarch/include/asm/branch.h

@@ -12,10 +12,9 @@ static inline unsigned long exception_era(struct pt_regs *regs)
 	return regs->csr_era;
 }
 
-static inline int compute_return_era(struct pt_regs *regs)
+static inline void compute_return_era(struct pt_regs *regs)
 {
 	regs->csr_era += 4;
-	return 0;
 }
 
 #endif /* _ASM_BRANCH_H */

arch/loongarch/kernel/traps.c

@@ -477,8 +477,7 @@ asmlinkage void noinstr do_ri(struct pt_regs *regs)
 
 	die_if_kernel("Reserved instruction in kernel code", regs);
 
-	if (unlikely(compute_return_era(regs) < 0))
-		goto out;
+	compute_return_era(regs);
 
 	if (unlikely(get_user(opcode, era) < 0)) {
 		status = SIGSEGV;