arm64: fault: avoid send SIGBUS two times

do_sea() calls arm64_notify_die() which will always signal
user-space. It also returns whether APEI claimed the external
abort as a RAS notification. If it returns failure do_mem_abort()
will signal user-space too.

do_mem_abort() wants to know if we handled the error, we always
call arm64_notify_die() so can always return success.
Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm64/mm/fault.c

@@ -574,7 +574,6 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 {
 	struct siginfo info;
 	const struct fault_info *inf;
-	int ret = 0;
 
 	inf = esr_to_fault_info(esr);
 	pr_err("Synchronous External Abort: %s (0x%08x) at 0x%016lx\n",
@@ -589,7 +588,7 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 		if (interrupts_enabled(regs))
 			nmi_enter();
 
-		ret = ghes_notify_sea();
+		ghes_notify_sea();
 
 		if (interrupts_enabled(regs))
 			nmi_exit();
@@ -604,7 +603,7 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 		info.si_addr  = (void __user *)addr;
 	arm64_notify_die("", regs, &info, esr);
 
-	return ret;
+	return 0;
 }
 
 static const struct fault_info fault_info[] = {