From patchwork Mon Jan 22 23:54:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 13526523 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A8FFE6EB41; Mon, 22 Jan 2024 23:56:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.55.52.120 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705967765; cv=none; b=rFAGpxveAolrAByYFCEG8E/1EOjj46ziqfSSMEvDOTZgbjWe4RpGZrhgX6jhvY3fSPATLY1HiaLcyXKJcMCJG0KIp467jUOZog9QnSWLuQUj+rWILvvmX7oAQJK8dglEZv6kkgJ1ZjTEQTn9zv0Gnxq9JIh5AKri5iBWvfzuEKY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705967765; c=relaxed/simple; bh=EHYPJXf4vg/icfK94eFCv7z0kKci7zJ4tVxjGwrDzJg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=MmjmFhhSh/uB0CS1eLzWDqdPifw0rhi/M1gqi7WBfDlGNnfiSS2dSA4MNlUEyJI7ABKJ734hqWScQt8VZdEph1sESRjeBMgZ8zXhB4tEKczuw2cHW4nBNqbujr9ewImYlWHjOdwb4ZbV0QeL6F5a9uA98D/BuUb1D5RDAEb3hp0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=bvPmFCM9; arc=none smtp.client-ip=192.55.52.120 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="bvPmFCM9" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1705967762; x=1737503762; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=EHYPJXf4vg/icfK94eFCv7z0kKci7zJ4tVxjGwrDzJg=; b=bvPmFCM9IT+n6s7FHs8HGbP2QWvrG4G7B26PiybJnMy+UuL5M38pgYPc MZvUzI7RCPHyr7UCOpA1o7Nuo7R+oA72zYIikDzIeBuJVhsPTe1fHG240 kA3vLDW5aqqVkQd/HJ85q7pOeTpFnx0Pa6FW6iNbnDJZPnm4M41o/IwNp zWTqdJCC3tj6hMqERUtjBVFQh27W4Vz29dZZFKIKEjOoj1ajnNVomM1fi ccOyAza7DqCYXNpfHzzvbKQUk0J3wDpbn+Cj5H3ADwZJr2iJVleowFN4T 3Ol8SV+eSdJa2BvwU1pBj0TWBvEoX78dpMEgN1eoM+kj0Q61cp9Omgk4C g==; X-IronPort-AV: E=McAfee;i="6600,9927,10961"; a="400217867" X-IronPort-AV: E=Sophos;i="6.05,212,1701158400"; d="scan'208";a="400217867" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jan 2024 15:55:52 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.05,212,1701158400"; d="scan'208";a="27817983" Received: from ls.sc.intel.com (HELO localhost) ([172.25.112.31]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jan 2024 15:55:51 -0800 From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sean Christopherson , Sagi Shahar , Kai Huang , chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com, Sean Christopherson Subject: [PATCH v18 099/121] KVM: TDX: Handle TDX PV MMIO hypercall Date: Mon, 22 Jan 2024 15:54:15 -0800 Message-Id: X-Mailer: git-send-email 2.25.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Sean Christopherson Export kvm_io_bus_read and kvm_mmio tracepoint and wire up TDX PV MMIO hypercall to the KVM backend functions. kvm_io_bus_read/write() searches KVM device emulated in kernel of the given MMIO address and emulates the MMIO. As TDX PV MMIO also needs it, export kvm_io_bus_read(). kvm_io_bus_write() is already exported. TDX PV MMIO emulates some of MMIO itself. To add trace point consistently with x86 kvm, export kvm_mmio tracepoint. Signed-off-by: Sean Christopherson Signed-off-by: Isaku Yamahata Reviewed-by: Paolo Bonzini --- arch/x86/kvm/vmx/tdx.c | 114 +++++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/x86.c | 1 + virt/kvm/kvm_main.c | 2 + 3 files changed, 117 insertions(+) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 71c444cfbc9e..bca1267b89bd 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1267,6 +1267,118 @@ static int tdx_emulate_io(struct kvm_vcpu *vcpu) return ret; } +static int tdx_complete_mmio(struct kvm_vcpu *vcpu) +{ + unsigned long val = 0; + gpa_t gpa; + int size; + + KVM_BUG_ON(vcpu->mmio_needed != 1, vcpu->kvm); + vcpu->mmio_needed = 0; + + if (!vcpu->mmio_is_write) { + gpa = vcpu->mmio_fragments[0].gpa; + size = vcpu->mmio_fragments[0].len; + + memcpy(&val, vcpu->run->mmio.data, size); + tdvmcall_set_return_val(vcpu, val); + trace_kvm_mmio(KVM_TRACE_MMIO_READ, size, gpa, &val); + } + return 1; +} + +static inline int tdx_mmio_write(struct kvm_vcpu *vcpu, gpa_t gpa, int size, + unsigned long val) +{ + if (kvm_iodevice_write(vcpu, &vcpu->arch.apic->dev, gpa, size, &val) && + kvm_io_bus_write(vcpu, KVM_MMIO_BUS, gpa, size, &val)) + return -EOPNOTSUPP; + + trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, size, gpa, &val); + return 0; +} + +static inline int tdx_mmio_read(struct kvm_vcpu *vcpu, gpa_t gpa, int size) +{ + unsigned long val; + + if (kvm_iodevice_read(vcpu, &vcpu->arch.apic->dev, gpa, size, &val) && + kvm_io_bus_read(vcpu, KVM_MMIO_BUS, gpa, size, &val)) + return -EOPNOTSUPP; + + tdvmcall_set_return_val(vcpu, val); + trace_kvm_mmio(KVM_TRACE_MMIO_READ, size, gpa, &val); + return 0; +} + +static int tdx_emulate_mmio(struct kvm_vcpu *vcpu) +{ + struct kvm_memory_slot *slot; + int size, write, r; + unsigned long val; + gpa_t gpa; + + KVM_BUG_ON(vcpu->mmio_needed, vcpu->kvm); + + size = tdvmcall_a0_read(vcpu); + write = tdvmcall_a1_read(vcpu); + gpa = tdvmcall_a2_read(vcpu); + val = write ? tdvmcall_a3_read(vcpu) : 0; + + if (size != 1 && size != 2 && size != 4 && size != 8) + goto error; + if (write != 0 && write != 1) + goto error; + + /* Strip the shared bit, allow MMIO with and without it set. */ + gpa = gpa & ~gfn_to_gpa(kvm_gfn_shared_mask(vcpu->kvm)); + + if (size > 8u || ((gpa + size - 1) ^ gpa) & PAGE_MASK) + goto error; + + slot = kvm_vcpu_gfn_to_memslot(vcpu, gpa_to_gfn(gpa)); + if (slot && !(slot->flags & KVM_MEMSLOT_INVALID)) + goto error; + + if (!kvm_io_bus_write(vcpu, KVM_FAST_MMIO_BUS, gpa, 0, NULL)) { + trace_kvm_fast_mmio(gpa); + return 1; + } + + if (write) + r = tdx_mmio_write(vcpu, gpa, size, val); + else + r = tdx_mmio_read(vcpu, gpa, size); + if (!r) { + /* Kernel completed device emulation. */ + tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS); + return 1; + } + + /* Request the device emulation to userspace device model. */ + vcpu->mmio_needed = 1; + vcpu->mmio_is_write = write; + vcpu->arch.complete_userspace_io = tdx_complete_mmio; + + vcpu->run->mmio.phys_addr = gpa; + vcpu->run->mmio.len = size; + vcpu->run->mmio.is_write = write; + vcpu->run->exit_reason = KVM_EXIT_MMIO; + + if (write) { + memcpy(vcpu->run->mmio.data, &val, size); + } else { + vcpu->mmio_fragments[0].gpa = gpa; + vcpu->mmio_fragments[0].len = size; + trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, size, gpa, NULL); + } + return 0; + +error: + tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND); + return 1; +} + static int handle_tdvmcall(struct kvm_vcpu *vcpu) { if (tdvmcall_exit_type(vcpu)) @@ -1279,6 +1391,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu) return tdx_emulate_hlt(vcpu); case EXIT_REASON_IO_INSTRUCTION: return tdx_emulate_io(vcpu); + case EXIT_REASON_EPT_VIOLATION: + return tdx_emulate_mmio(vcpu); default: break; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 614d0bccfde2..ac934542b086 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -13935,6 +13935,7 @@ EXPORT_SYMBOL_GPL(kvm_sev_es_string_io); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit); +EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_mmio); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq); EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 912a6179c03c..afff3175a731 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2689,6 +2689,7 @@ struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn return NULL; } +EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_memslot); bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn) { @@ -5925,6 +5926,7 @@ int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr, r = __kvm_io_bus_read(vcpu, bus, &range, val); return r < 0 ? r : 0; } +EXPORT_SYMBOL_GPL(kvm_io_bus_read); int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, int len, struct kvm_io_device *dev)