From patchwork Tue Aug 6 18:40:53 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoffer Dall X-Patchwork-Id: 2839538 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 54467BF535 for ; Tue, 6 Aug 2013 18:41:38 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2904C20222 for ; Tue, 6 Aug 2013 18:41:37 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B5D912012D for ; Tue, 6 Aug 2013 18:41:35 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V6mCL-0002HL-Lt; Tue, 06 Aug 2013 18:41:33 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1V6mCJ-0006IF-Ft; Tue, 06 Aug 2013 18:41:31 +0000 Received: from mail-pb0-f45.google.com ([209.85.160.45]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V6mCG-0006HP-Ox for linux-arm-kernel@lists.infradead.org; Tue, 06 Aug 2013 18:41:29 +0000 Received: by mail-pb0-f45.google.com with SMTP id mc17so818333pbc.32 for ; Tue, 06 Aug 2013 11:41:07 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=edmR6cS1Z5LoKljYXcTH46/vZWwAtSs56xN+3ULT4Cw=; b=B/vdPqkea3u43QtAj2B0ZTl1eI+1z6Py4gsHM84Y+osjB/wjQwLyAAFKvTktHRHWgS 93sco2menO+G4H9klB9A6xC48ZE11eZLxrTpAISqpVdM2Jt+uhrU+rm/c7qPiV3kE1oZ ESuBrwBQ/mEBKO7vf0VeQJP1YyTxLKAmGKBGs4E0TgrTGJECkR8hHIwzRhWuOYzxBlge 7SHHrZRT2V7qGQrxxHrGIzbm2dzdHUlgJiHrqAgGNefbDGBxUIT2Ho/YW6r3ULLxTl6s +wIZlQqbwaag26HEjuM8QDV07uQDCsWpqZMAcnZxENhG7zTdKcxboyR2FDpydKO0kOhZ A/vw== X-Gm-Message-State: ALoCoQnePvvKHX+TVetw9TXLH38cEayL/JLHqd0hNvb3J/jOTGu5CEHJpTkiXzs0quKTE6C/5R5V X-Received: by 10.69.0.9 with SMTP id au9mr3131310pbd.62.1375814466996; Tue, 06 Aug 2013 11:41:06 -0700 (PDT) Received: from localhost.localdomain (c-67-169-183-77.hsd1.ca.comcast.net. [67.169.183.77]) by mx.google.com with ESMTPSA id om2sm3409768pbc.30.2013.08.06.11.41.05 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 06 Aug 2013 11:41:06 -0700 (PDT) From: Christoffer Dall To: kvmarm@lists.cs.columbia.edu Subject: [PATCH v2] ARM: KVM: Fix 64-bit coprocessor handling Date: Tue, 6 Aug 2013 11:40:53 -0700 Message-Id: <1375814453-8425-1-git-send-email-christoffer.dall@linaro.org> X-Mailer: git-send-email 1.7.10.4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130806_144128_978206_78058D43 X-CRM114-Status: GOOD ( 15.20 ) X-Spam-Score: -2.6 (--) Cc: linaro-kernel@lists.linaro.org, kvm@vger.kernel.org, patches@linaro.org, Marc Zyngier , linux-arm-kernel@lists.infradead.org, Christoffer Dall X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The PAR was exported as CRn == 7 and CRm == 0, but in fact the primary coprocessor register number was determined by CRm for 64-bit coprocessor registers as the user space API was modeled after the coprocessor access instructions (see the ARM ARM rev. C - B3-1445). However, just changing the CRn to CRm breaks the sorting check when booting the kernel, because the internal kernel logic always treats CRn as the primary register number, and it makes the table sorting impossible to understand for humans. Alternatively we could change the logic to always have CRn == CRm, but that becomes unclear in the number of ways we do look up of a coprocessor register. We could also have a separate 64-bit table but that feels somewhat over-engineered. Instead, keep CRn the primary representation of the primary coproc. register number in-kernel and always export the primary number as CRm as per the existing user space ABI. Note: The TTBR registers just magically worked because they happened to follow the CRn(0) regs and were considered CRn(0) in the in-kernel representation. Cc: Marc Zyngier Signed-off-by: Christoffer Dall --- [Changes v1 -> v2]: - Use CRm64 macro as suggested by Marc Zyngier - Fix spelling issues arch/arm/kvm/coproc.c | 26 +++++++++++++++++++------- arch/arm/kvm/coproc.h | 3 +++ arch/arm/kvm/coproc_a15.c | 6 +++++- 3 files changed, 27 insertions(+), 8 deletions(-) diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c index 4a51990..db9cf69 100644 --- a/arch/arm/kvm/coproc.c +++ b/arch/arm/kvm/coproc.c @@ -146,7 +146,11 @@ static bool pm_fake(struct kvm_vcpu *vcpu, #define access_pmintenclr pm_fake /* Architected CP15 registers. - * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 + * CRn denotes the primary register number, but is copied to the CRm in the + * user space API for 64-bit register access in line with the terminology used + * in the ARM ARM. + * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 and with 64-bit + * registers preceding 32-bit ones. */ static const struct coproc_reg cp15_regs[] = { /* CSSELR: swapped by interrupt.S. */ @@ -154,8 +158,8 @@ static const struct coproc_reg cp15_regs[] = { NULL, reset_unknown, c0_CSSELR }, /* TTBR0/TTBR1: swapped by interrupt.S. */ - { CRm( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 }, - { CRm( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 }, + { CRm64( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 }, + { CRm64( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 }, /* TTBCR: swapped by interrupt.S. */ { CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32, @@ -182,7 +186,7 @@ static const struct coproc_reg cp15_regs[] = { NULL, reset_unknown, c6_IFAR }, /* PAR swapped by interrupt.S */ - { CRn( 7), Op1( 0), is64, NULL, reset_unknown64, c7_PAR }, + { CRm64( 7), Op1( 0), is64, NULL, reset_unknown64, c7_PAR }, /* * DC{C,I,CI}SW operations: @@ -399,12 +403,13 @@ static bool index_to_params(u64 id, struct coproc_params *params) | KVM_REG_ARM_OPC1_MASK)) return false; params->is_64bit = true; - params->CRm = ((id & KVM_REG_ARM_CRM_MASK) + /* CRm to CRn: see cp15_to_index for details */ + params->CRn = ((id & KVM_REG_ARM_CRM_MASK) >> KVM_REG_ARM_CRM_SHIFT); params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK) >> KVM_REG_ARM_OPC1_SHIFT); params->Op2 = 0; - params->CRn = 0; + params->CRm = 0; return true; default: return false; @@ -898,7 +903,14 @@ static u64 cp15_to_index(const struct coproc_reg *reg) if (reg->is_64) { val |= KVM_REG_SIZE_U64; val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT); - val |= (reg->CRm << KVM_REG_ARM_CRM_SHIFT); + /* + * CRn always denotes the primary coproc. reg. nr. for the + * in-kernel representation, but the user space API uses the + * CRm for the encoding, because it is modelled after the + * MRRC/MCRR instructions: see the ARM ARM rev. c page + * B3-1445 + */ + val |= (reg->CRn << KVM_REG_ARM_CRM_SHIFT); } else { val |= KVM_REG_SIZE_U32; val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT); diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h index b7301d3..0461d5c 100644 --- a/arch/arm/kvm/coproc.h +++ b/arch/arm/kvm/coproc.h @@ -135,6 +135,8 @@ static inline int cmp_reg(const struct coproc_reg *i1, return -1; if (i1->CRn != i2->CRn) return i1->CRn - i2->CRn; + if (i1->is_64 != i2->is_64) + return i2->is_64 - i1->is_64; if (i1->CRm != i2->CRm) return i1->CRm - i2->CRm; if (i1->Op1 != i2->Op1) @@ -145,6 +147,7 @@ static inline int cmp_reg(const struct coproc_reg *i1, #define CRn(_x) .CRn = _x #define CRm(_x) .CRm = _x +#define CRm64(_x) .CRn = _x, .CRm = 0 #define Op1(_x) .Op1 = _x #define Op2(_x) .Op2 = _x #define is64 .is_64 = true diff --git a/arch/arm/kvm/coproc_a15.c b/arch/arm/kvm/coproc_a15.c index 685063a..cf93472 100644 --- a/arch/arm/kvm/coproc_a15.c +++ b/arch/arm/kvm/coproc_a15.c @@ -114,7 +114,11 @@ static bool access_l2ectlr(struct kvm_vcpu *vcpu, /* * A15-specific CP15 registers. - * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 + * CRn denotes the primary register number, but is copied to the CRm in the + * user space API for 64-bit register access in line with the terminology used + * in the ARM ARM. + * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 and with 64-bit + * registers preceding 32-bit ones. */ static const struct coproc_reg a15_regs[] = { /* MPIDR: we use VMPIDR for guest access. */