From mboxrd@z Thu Jan 1 00:00:00 1970 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 67C52CF65F1 for ; Mon, 26 Jan 2026 12:18:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=onjDqlTOMWI8ZHCwAMNlWqocnMp1H7tfe//+SWdg78g=; b=jZp3uosXPYJpHRpnaaGE5cB6tq HKJOdfs9fpXZkKhE66sr6hp+BBVSVy5Smm7fDHVDsIp8E5I0W0+waHM6X/IWpST3U3Mdg1xd2RyCG avVtTMa6sVbgazGbiW1Ckq9bzaedTdbpcbSrSpyQP3V0OjYZ6VzjYfnhbXZFPZvDTGGGroEhN0kPZ /xVq0xWNReW58/OT7ht27rSQ89EML8GC153UK2rs+QSJWGMccimKkTi+k1ocHhAV3ROEqC54QSF+U GW+eod9mxMBFgHgIFFLcEt7SEgKRUekSeOR9ojc8/cS3HxNnPA5xC9Lk5HJMWKoMbpv6OENSXEPro M/zyYSag==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vkLXY-0000000CVE6-2ErF; Mon, 26 Jan 2026 12:17:56 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vkLXG-0000000CUwP-23x9 for linux-arm-kernel@lists.infradead.org; Mon, 26 Jan 2026 12:17:41 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 2A98C44426; Mon, 26 Jan 2026 12:17:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 093AAC116C6; Mon, 26 Jan 2026 12:17:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769429858; bh=rJgheB6THcstxt2wbh5QI4RzkAO+EKvuEAN0WWCmPRA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KxYqgDIvPwCgbKnPAopDR2//Jz9pVsvT5YHWC738jTDv4KBhEAyrwcrY/NyqNNJOA KUHBstcoKcMAdw6bGLLDK+mgfbJMd4nF6ew6cxdXvGv/KwM6ilQwhjr3j4SLSLJj+/ nuHt7kh9EpaEJ2kKQkt949FoyRmYnFNsEV7MbnNOycVyIolEhAp43rgfPEvteYHJCN bi1cPvc7dRaiEO9gCF1hl4toIe/Sd7pubnURSoyovO38m7LkhQGpS3KmsnS02NG1C3 Q3xtsDgoTEwHdOh8NpDj6WXzpRweM4FwqfwI+h4RQXyQP6MuoF4PJYc7eK/kTdXPqS BgRQqAajx4Pog== 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 4.98.2) (envelope-from ) id 1vkLXE-00000005hx6-1DLf; Mon, 26 Jan 2026 12:17:36 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Cc: Joey Gouly , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Fuad Tabba , Will Deacon , Catalin Marinas Subject: [PATCH 20/20] KVM: arm64: Add debugfs file dumping computed RESx values Date: Mon, 26 Jan 2026 12:16:54 +0000 Message-ID: <20260126121655.1641736-21-maz@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260126121655.1641736-1-maz@kernel.org> References: <20260126121655.1641736-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, joey.gouly@arm.com, suzuki.poulose@arm.com, oupton@kernel.org, yuzenghui@huawei.com, tabba@google.com, will@kernel.org, catalin.marinas@arm.com 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-20260126_041738_597954_6CC196E9 X-CRM114-Status: GOOD ( 16.04 ) 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 Computing RESx values is hard. Verifying that they are correct is harder. Add a debugfs file called "resx" that will dump all the RESx values for a given VM. I found it useful, maybe you will too. Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_host.h | 1 + arch/arm64/kvm/sys_regs.c | 98 +++++++++++++++++++++++++++++++ 2 files changed, 99 insertions(+) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index c82b071ade2a5..54072f6ec9d4b 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -375,6 +375,7 @@ struct kvm_arch { /* Iterator for idreg debugfs */ u8 idreg_debugfs_iter; + u16 sr_resx_iter; /* Hypercall features firmware registers' descriptor */ struct kvm_smccc_features smccc_feat; diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 88a57ca36d96c..f3f92b489b588 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -5090,12 +5090,110 @@ static const struct seq_operations idregs_debug_sops = { DEFINE_SEQ_ATTRIBUTE(idregs_debug); +static const struct sys_reg_desc *sr_resx_find(struct kvm *kvm, u16 pos) +{ + unsigned long i, sr_idx = 0; + + for (i = 0; i < ARRAY_SIZE(sys_reg_descs); i++) { + const struct sys_reg_desc *r = &sys_reg_descs[i]; + + if (r->reg < __SANITISED_REG_START__) + continue; + + if (sr_idx == pos) + return r; + + sr_idx++; + } + + return NULL; +} + +static void *sr_resx_start(struct seq_file *s, loff_t *pos) +{ + struct kvm *kvm = s->private; + u16 *iter; + + guard(mutex)(&kvm->arch.config_lock); + + if (!kvm->arch.sysreg_masks) + return NULL; + + iter = &kvm->arch.sr_resx_iter; + if (*iter != (u16)~0) + return ERR_PTR(-EBUSY); + + *iter = *pos; + if (!sr_resx_find(kvm, *iter)) + iter = NULL; + + return iter; +} + +static void *sr_resx_next(struct seq_file *s, void *v, loff_t *pos) +{ + struct kvm *kvm = s->private; + + (*pos)++; + + if (sr_resx_find(kvm, kvm->arch.sr_resx_iter + 1)) { + kvm->arch.sr_resx_iter++; + + return &kvm->arch.sr_resx_iter; + } + + return NULL; +} + +static void sr_resx_stop(struct seq_file *s, void *v) +{ + struct kvm *kvm = s->private; + + if (IS_ERR(v)) + return; + + guard(mutex)(&kvm->arch.config_lock); + + kvm->arch.sr_resx_iter = ~0; +} + +static int sr_resx_show(struct seq_file *s, void *v) +{ + const struct sys_reg_desc *desc; + struct kvm *kvm = s->private; + struct resx resx; + + desc = sr_resx_find(kvm, kvm->arch.sr_resx_iter); + + if (!desc->name) + return 0; + + resx = kvm_get_sysreg_resx(kvm, desc->reg); + + seq_printf(s, "%20s:\tRES0:%016llx\tRES1:%016llx\n", + desc->name, resx.res0, resx.res1); + + return 0; +} + +static const struct seq_operations sr_resx_sops = { + .start = sr_resx_start, + .next = sr_resx_next, + .stop = sr_resx_stop, + .show = sr_resx_show, +}; + +DEFINE_SEQ_ATTRIBUTE(sr_resx); + void kvm_sys_regs_create_debugfs(struct kvm *kvm) { kvm->arch.idreg_debugfs_iter = ~0; + kvm->arch.sr_resx_iter = ~0; debugfs_create_file("idregs", 0444, kvm->debugfs_dentry, kvm, &idregs_debug_fops); + debugfs_create_file("resx", 0444, kvm->debugfs_dentry, kvm, + &sr_resx_fops); } static void reset_vm_ftr_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *reg) -- 2.47.3