From patchwork Mon Jan 22 20:18:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13526222 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 22E63C47DD3 for ; Mon, 22 Jan 2024 20:20:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=CzCTDP98hyaxJSVH43aZXstgrNAZYwTTBYKbXpU21YQ=; b=frXVe9fAz4G3mc elYGWg19M6wToHdb9RNJLWBldDU3gh4zg6stx+3y0WON+Y/yKVl4wWMh9JtOnQy2+4tXZS/dviHLP 2vSu3IpNilPN6TDSvdyKrW3m5ip3Z+H7xSRPQhLANExQ6WbJHMyakOlktbx87hL67OWtG2UC6J5bc uAZQ5GADjW2sSQclL9ACYrbkNVXDkOBgwjGRQbUSTPNNl+PyCkFHV21B7IZcDue+6olM835V0/aai uM0iBW5TJDYRgkbJqmdVDrj7rlXR68elQ0rdeD+wHvCbPIh9Lq5SIlH1VfK1qG6Rbwr5mOx2CeqmZ dLaNO59gU6b2pb6ZE/tQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rS0lT-00DsF1-1a; Mon, 22 Jan 2024 20:19:27 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rS0l5-00DrrK-31 for linux-arm-kernel@lists.infradead.org; Mon, 22 Jan 2024 20:19:07 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id CE09F61A1D; Mon, 22 Jan 2024 20:19:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D571C433A6; Mon, 22 Jan 2024 20:19:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705954742; bh=qY2D63nr7CXZXtPqpmI7dtxD0dAWJWy0xSTh5/zrD7s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SjM7a8GZWgNffa6vPtmh5KcZlWafesLra3V+pLzv6Uj51DJA/pr4XbvrwJH0bhbwK c49/g8f+9H3iaUcR+XbSRzuUToW4MBs7SGS40+D30G+8cJGTQC4KJpgZ2HHN7VBPIe La+HSRa/Vf1pfMWCuEEKxvcRK5//gnk8qOZkfDdqzuX5dOsQuvZrlXSMRS6t38gpce ricn7bgDfyp3+hgaF9YDusPlezRP8LLbIQWys98j4Zl9p/p75sSjQxBCZAWLrWnaDG jSiS2qXknnZfYh4pY3yFiGSqa+dkMuaD/J7o+RCpDu/4UmstXRINGFa03BliljLRYA XXIp5ozUZNgPw== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1rS0l2-00DjkQ-GI; Mon, 22 Jan 2024 20:19:00 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org Cc: James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Catalin Marinas , Will Deacon , Joey Gouly , Mark Brown Subject: [PATCH 25/25] KVM: arm64: Add debugfs file for guest's ID registers Date: Mon, 22 Jan 2024 20:18:52 +0000 Message-Id: <20240122201852.262057-26-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240122201852.262057-1-maz@kernel.org> References: <20240122201852.262057-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, joey.gouly@arm.com, broonie@kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240122_121904_086443_6B3D3A12 X-CRM114-Status: GOOD ( 17.09 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Debugging ID register setup can be a complicated affair. Give the kernel hacker a way to dump that state in an easy to parse way. Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_host.h | 3 ++ arch/arm64/kvm/sys_regs.c | 81 +++++++++++++++++++++++++++++++ 2 files changed, 84 insertions(+) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 22343354db3e..065e2deb3ea4 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -319,6 +319,9 @@ struct kvm_arch { /* PMCR_EL0.N value for the guest */ u8 pmcr_n; + /* Iterator for idreg debugfs */ + u8 idreg_debugfs_iter; + /* Hypercall features firmware registers' descriptor */ struct kvm_smccc_features smccc_feat; struct maple_tree smccc_filter; diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index b7977e08e4ef..3278ba0d0347 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -3423,6 +3424,81 @@ static bool emulate_sys_reg(struct kvm_vcpu *vcpu, return false; } +static void *idregs_debug_start(struct seq_file *s, loff_t *pos) +{ + struct kvm *kvm = s->private; + u8 *iter; + + mutex_lock(&kvm->arch.config_lock); + + iter = &kvm->arch.idreg_debugfs_iter; + if (*iter == (u8)~0) { + *iter = *pos; + if (*iter >= KVM_ARM_ID_REG_NUM) + iter = NULL; + } else { + iter = ERR_PTR(-EBUSY); + } + + mutex_unlock(&kvm->arch.config_lock); + + return iter; +} + +static void *idregs_debug_next(struct seq_file *s, void *v, loff_t *pos) +{ + struct kvm *kvm = s->private; + + (*pos)++; + + if ((kvm->arch.idreg_debugfs_iter + 1) < KVM_ARM_ID_REG_NUM) { + kvm->arch.idreg_debugfs_iter++; + + return &kvm->arch.idreg_debugfs_iter; + } + + return NULL; +} + +static void idregs_debug_stop(struct seq_file *s, void *v) +{ + struct kvm *kvm = s->private; + + if (IS_ERR(v)) + return; + + mutex_lock(&kvm->arch.config_lock); + + kvm->arch.idreg_debugfs_iter = ~0; + + mutex_unlock(&kvm->arch.config_lock); +} + +static int idregs_debug_show(struct seq_file *s, void *v) +{ + struct kvm *kvm = s->private; + const struct sys_reg_desc *desc; + + desc = first_idreg + kvm->arch.idreg_debugfs_iter; + + if (!desc->name) + return 0; + + seq_printf(s, "%20s:\t%016llx\n", + desc->name, IDREG(kvm, IDX_IDREG(kvm->arch.idreg_debugfs_iter))); + + return 0; +} + +static const struct seq_operations idregs_debug_sops = { + .start = idregs_debug_start, + .next = idregs_debug_next, + .stop = idregs_debug_stop, + .show = idregs_debug_show, +}; + +DEFINE_SEQ_ATTRIBUTE(idregs_debug); + static void kvm_reset_id_regs(struct kvm_vcpu *vcpu) { const struct sys_reg_desc *idreg = first_idreg; @@ -3442,6 +3518,11 @@ static void kvm_reset_id_regs(struct kvm_vcpu *vcpu) id = reg_to_encoding(idreg); } + kvm->arch.idreg_debugfs_iter = ~0; + + debugfs_create_file("idregs", 0444, kvm->debugfs_dentry, kvm, + &idregs_debug_fops); + set_bit(KVM_ARCH_FLAG_ID_REGS_INITIALIZED, &kvm->arch.flags); }