From patchwork Wed Jul 31 17:36:47 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 11068933 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A85B11395 for ; Wed, 31 Jul 2019 17:37:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9010B1FFBE for ; Wed, 31 Jul 2019 17:37:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 83AFC228C9; Wed, 31 Jul 2019 17:37:08 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1DFD11FFBE for ; Wed, 31 Jul 2019 17:37:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728232AbfGaRhH (ORCPT ); Wed, 31 Jul 2019 13:37:07 -0400 Received: from foss.arm.com ([217.140.110.172]:52480 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727125AbfGaRhH (ORCPT ); Wed, 31 Jul 2019 13:37:07 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 35BDC1596; Wed, 31 Jul 2019 10:37:06 -0700 (PDT) Received: from big-swifty.lan (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1D8E13F71F; Wed, 31 Jul 2019 10:37:02 -0700 (PDT) From: Marc Zyngier To: Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= Cc: Anders Roxell , Andrew Murray , James Morse , Julien Thierry , Zenghui Yu , Suzuki K Poulose , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Subject: [PATCH 2/5] arm64: KVM: regmap: Fix unexpected switch fall-through Date: Wed, 31 Jul 2019 18:36:47 +0100 Message-Id: <20190731173650.12627-3-maz@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190731173650.12627-1-maz@kernel.org> References: <20190731173650.12627-1-maz@kernel.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Anders Roxell When fall-through warnings was enabled by default, commit d93512ef0f0e ("Makefile: Globally enable fall-through warning"), the following warnings was starting to show up: In file included from ../arch/arm64/include/asm/kvm_emulate.h:19, from ../arch/arm64/kvm/regmap.c:13: ../arch/arm64/kvm/regmap.c: In function ‘vcpu_write_spsr32’: ../arch/arm64/include/asm/kvm_hyp.h:31:3: warning: this statement may fall through [-Wimplicit-fallthrough=] asm volatile(ALTERNATIVE(__msr_s(r##nvh, "%x0"), \ ^~~ ../arch/arm64/include/asm/kvm_hyp.h:46:31: note: in expansion of macro ‘write_sysreg_elx’ #define write_sysreg_el1(v,r) write_sysreg_elx(v, r, _EL1, _EL12) ^~~~~~~~~~~~~~~~ ../arch/arm64/kvm/regmap.c:180:3: note: in expansion of macro ‘write_sysreg_el1’ write_sysreg_el1(v, SYS_SPSR); ^~~~~~~~~~~~~~~~ ../arch/arm64/kvm/regmap.c:181:2: note: here case KVM_SPSR_ABT: ^~~~ In file included from ../arch/arm64/include/asm/cputype.h:132, from ../arch/arm64/include/asm/cache.h:8, from ../include/linux/cache.h:6, from ../include/linux/printk.h:9, from ../include/linux/kernel.h:15, from ../include/asm-generic/bug.h:18, from ../arch/arm64/include/asm/bug.h:26, from ../include/linux/bug.h:5, from ../include/linux/mmdebug.h:5, from ../include/linux/mm.h:9, from ../arch/arm64/kvm/regmap.c:11: ../arch/arm64/include/asm/sysreg.h:837:2: warning: this statement may fall through [-Wimplicit-fallthrough=] asm volatile("msr " __stringify(r) ", %x0" \ ^~~ ../arch/arm64/kvm/regmap.c:182:3: note: in expansion of macro ‘write_sysreg’ write_sysreg(v, spsr_abt); ^~~~~~~~~~~~ ../arch/arm64/kvm/regmap.c:183:2: note: here case KVM_SPSR_UND: ^~~~ Rework to add a 'break;' in the swich-case since it didn't have that, leading to an interresting set of bugs. Cc: stable@vger.kernel.org # v4.17+ Fixes: a892819560c4 ("KVM: arm64: Prepare to handle deferred save/restore of 32-bit registers") Signed-off-by: Anders Roxell [maz: reworked commit message, fixed stable range] Signed-off-by: Marc Zyngier --- arch/arm64/kvm/regmap.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm64/kvm/regmap.c b/arch/arm64/kvm/regmap.c index 0d60e4f0af66..a900181e3867 100644 --- a/arch/arm64/kvm/regmap.c +++ b/arch/arm64/kvm/regmap.c @@ -178,13 +178,18 @@ void vcpu_write_spsr32(struct kvm_vcpu *vcpu, unsigned long v) switch (spsr_idx) { case KVM_SPSR_SVC: write_sysreg_el1(v, SYS_SPSR); + break; case KVM_SPSR_ABT: write_sysreg(v, spsr_abt); + break; case KVM_SPSR_UND: write_sysreg(v, spsr_und); + break; case KVM_SPSR_IRQ: write_sysreg(v, spsr_irq); + break; case KVM_SPSR_FIQ: write_sysreg(v, spsr_fiq); + break; } }