From patchwork Thu Jun 23 01:49:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Zhongjin X-Patchwork-Id: 12891666 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA79FC19F56 for ; Thu, 23 Jun 2022 01:53:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378123AbiFWBxZ (ORCPT ); Wed, 22 Jun 2022 21:53:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377637AbiFWBwb (ORCPT ); Wed, 22 Jun 2022 21:52:31 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BAD4843EC5; Wed, 22 Jun 2022 18:51:54 -0700 (PDT) Received: from dggpemm500020.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4LT37J1xxkzShCC; Thu, 23 Jun 2022 09:48:28 +0800 (CST) Received: from dggpemm500013.china.huawei.com (7.185.36.172) by dggpemm500020.china.huawei.com (7.185.36.49) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 23 Jun 2022 09:51:53 +0800 Received: from ubuntu1804.huawei.com (10.67.175.36) by dggpemm500013.china.huawei.com (7.185.36.172) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 23 Jun 2022 09:51:52 +0800 From: Chen Zhongjin To: , , , , , CC: , , , , , , , , , , , , , , Subject: [PATCH v6 32/33] arm64: irq-gic: Replace unreachable() with -EINVAL Date: Thu, 23 Jun 2022 09:49:16 +0800 Message-ID: <20220623014917.199563-33-chenzhongjin@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220623014917.199563-1-chenzhongjin@huawei.com> References: <20220623014917.199563-1-chenzhongjin@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.67.175.36] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500013.china.huawei.com (7.185.36.172) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Using unreachable() at default of switch generates an extra branch at end of the function, and compiler won't generate a ret to close this branch because it knows it's unreachable. If there's no instruction in this branch, compiler will generate a NOP, And it will confuse objtool to warn this NOP as a fall through branch. In fact these branches are actually unreachable, so we can replace unreachable() with returning a -EINVAL value. Signed-off-by: Chen Zhongjin --- arch/arm64/kvm/hyp/vgic-v3-sr.c | 7 +++---- drivers/irqchip/irq-gic-v3.c | 2 +- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kvm/hyp/vgic-v3-sr.c b/arch/arm64/kvm/hyp/vgic-v3-sr.c index 4fb419f7b8b6..f3cee92c3038 100644 --- a/arch/arm64/kvm/hyp/vgic-v3-sr.c +++ b/arch/arm64/kvm/hyp/vgic-v3-sr.c @@ -6,7 +6,6 @@ #include -#include #include #include @@ -55,7 +54,7 @@ static u64 __gic_v3_get_lr(unsigned int lr) return read_gicreg(ICH_LR15_EL2); } - unreachable(); + return -EINVAL; } static void __gic_v3_set_lr(u64 val, int lr) @@ -166,7 +165,7 @@ static u32 __vgic_v3_read_ap0rn(int n) val = read_gicreg(ICH_AP0R3_EL2); break; default: - unreachable(); + val = -EINVAL; } return val; @@ -190,7 +189,7 @@ static u32 __vgic_v3_read_ap1rn(int n) val = read_gicreg(ICH_AP1R3_EL2); break; default: - unreachable(); + val = -EINVAL; } return val; diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index b252d5534547..2ef98e32d257 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -475,7 +475,7 @@ static u32 __gic_get_ppi_index(irq_hw_number_t hwirq) case EPPI_RANGE: return hwirq - EPPI_BASE_INTID + 16; default: - unreachable(); + return -EINVAL; } }