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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 996D3C4332F for ; Tue, 5 Apr 2022 10:08:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352960AbiDEKFY (ORCPT ); Tue, 5 Apr 2022 06:05:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52752 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239125AbiDEIbL (ORCPT ); Tue, 5 Apr 2022 04:31:11 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 19740496B3; Tue, 5 Apr 2022 01:23:10 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 5828CB81BD6; Tue, 5 Apr 2022 08:23:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C48E5C385B4; Tue, 5 Apr 2022 08:23:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649146988; bh=Iq2ZvXe9ADabMGnOc1m2KwnYvzAf0dQnMn6C1TUJ2QA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jEY5HTEuUy52xcqnIf3YhC79PsF4NV9Ez311b1I8w7cw54TDTQpx4V2LMLcM7NTSW djcUOZXEdhPSFzlrPnS5xcuq/JL5SNG7DDm/tb8Hlr4+W5/eeUAqb7LDXqp0aKIGcs TVpkDAB+9/iAfYW15JKFCoAjZvL3p+MXHc/58NbM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vitaly Kuznetsov , Paolo Bonzini Subject: [PATCH 5.17 0959/1126] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall Date: Tue, 5 Apr 2022 09:28:26 +0200 Message-Id: <20220405070435.653745066@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070407.513532867@linuxfoundation.org> References: <20220405070407.513532867@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vitaly Kuznetsov commit 47d3e5cdfe607ec6883eb0faa7acf05b8cb3f92a upstream. It has been proven on practice that at least Windows Server 2019 tries using HVCALL_SEND_IPI_EX in 'XMM fast' mode when it has more than 64 vCPUs and it needs to send an IPI to a vCPU > 63. Similarly to other XMM Fast hypercalls (HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}{,_EX}), this information is missing in TLFS as of 6.0b. Currently, KVM returns an error (HV_STATUS_INVALID_HYPERCALL_INPUT) and Windows crashes. Note, HVCALL_SEND_IPI is a 'standard' fast hypercall (not 'XMM fast') as all its parameters fit into RDX:R8 and this is handled by KVM correctly. Cc: stable@vger.kernel.org # 5.14.x: 3244867af8c0: KVM: x86: Ignore sparse banks size for an "all CPUs", non-sparse IPI req Cc: stable@vger.kernel.org # 5.14.x Fixes: d8f5537a8816 ("KVM: hyper-v: Advertise support for fast XMM hypercalls") Signed-off-by: Vitaly Kuznetsov Message-Id: <20220222154642.684285-5-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/hyperv.c | 52 ++++++++++++++++++++++++++++++++------------------ 1 file changed, 34 insertions(+), 18 deletions(-) --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1890,6 +1890,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vc int sparse_banks_len; u32 vector; bool all_cpus; + int i; if (hc->code == HVCALL_SEND_IPI) { if (!hc->fast) { @@ -1910,9 +1911,15 @@ static u64 kvm_hv_send_ipi(struct kvm_vc trace_kvm_hv_send_ipi(vector, sparse_banks[0]); } else { - if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex, - sizeof(send_ipi_ex)))) - return HV_STATUS_INVALID_HYPERCALL_INPUT; + if (!hc->fast) { + if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex, + sizeof(send_ipi_ex)))) + return HV_STATUS_INVALID_HYPERCALL_INPUT; + } else { + send_ipi_ex.vector = (u32)hc->ingpa; + send_ipi_ex.vp_set.format = hc->outgpa; + send_ipi_ex.vp_set.valid_bank_mask = sse128_lo(hc->xmm[0]); + } trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector, send_ipi_ex.vp_set.format, @@ -1920,8 +1927,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vc vector = send_ipi_ex.vector; valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask; - sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) * - sizeof(sparse_banks[0]); + sparse_banks_len = bitmap_weight(&valid_bank_mask, 64); all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL; @@ -1931,12 +1937,27 @@ static u64 kvm_hv_send_ipi(struct kvm_vc if (!sparse_banks_len) goto ret_success; - if (kvm_read_guest(kvm, - hc->ingpa + offsetof(struct hv_send_ipi_ex, - vp_set.bank_contents), - sparse_banks, - sparse_banks_len)) - return HV_STATUS_INVALID_HYPERCALL_INPUT; + if (!hc->fast) { + if (kvm_read_guest(kvm, + hc->ingpa + offsetof(struct hv_send_ipi_ex, + vp_set.bank_contents), + sparse_banks, + sparse_banks_len * sizeof(sparse_banks[0]))) + return HV_STATUS_INVALID_HYPERCALL_INPUT; + } else { + /* + * The lower half of XMM0 is already consumed, each XMM holds + * two sparse banks. + */ + if (sparse_banks_len > (2 * HV_HYPERCALL_MAX_XMM_REGISTERS - 1)) + return HV_STATUS_INVALID_HYPERCALL_INPUT; + for (i = 0; i < sparse_banks_len; i++) { + if (i % 2) + sparse_banks[i] = sse128_lo(hc->xmm[(i + 1) / 2]); + else + sparse_banks[i] = sse128_hi(hc->xmm[i / 2]); + } + } } check_and_send_ipi: @@ -2098,6 +2119,7 @@ static bool is_xmm_fast_hypercall(struct case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE: case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX: case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX: + case HVCALL_SEND_IPI_EX: return true; } @@ -2265,14 +2287,8 @@ int kvm_hv_hypercall(struct kvm_vcpu *vc ret = kvm_hv_flush_tlb(vcpu, &hc); break; case HVCALL_SEND_IPI: - if (unlikely(hc.rep)) { - ret = HV_STATUS_INVALID_HYPERCALL_INPUT; - break; - } - ret = kvm_hv_send_ipi(vcpu, &hc); - break; case HVCALL_SEND_IPI_EX: - if (unlikely(hc.fast || hc.rep)) { + if (unlikely(hc.rep)) { ret = HV_STATUS_INVALID_HYPERCALL_INPUT; break; }