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 C4218CDB483 for ; Wed, 18 Oct 2023 01:10:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344258AbjJRBKR (ORCPT ); Tue, 17 Oct 2023 21:10:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45242 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229463AbjJRBKP (ORCPT ); Tue, 17 Oct 2023 21:10:15 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 75CCDB6 for ; Tue, 17 Oct 2023 18:10:14 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id 41be03b00d2f7-5b7179ff4easo2441183a12.0 for ; Tue, 17 Oct 2023 18:10:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1697591414; x=1698196214; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=E16mHWskjTK/3B68Q/Af3Teg1/R8lnVGjDiVWL3Gi8c=; b=XxajgS6DEeyskLQvwZCq4+hzkNK3/lfws5r3oQW+RYnw1cUNQRQ9Kg5K16vDWNnPNI YtjXOsod+tCYYiFHg3UG+nWORmehgOBNKWh4u5bjGVC5yHCOvPmRyjbiSCaQ7woanc5T U2DJLNWabXj0YEqKMt9R7MkrIPNDxosa/6HkNY8Sle74XM4dtNGsK8XMMdDj2+hjaaBh iohbD/a80XQ6ZaurfgjXQUwmQ0ddWtzLwh5yjLWcznMWbqBqZXuFm1gdjYrlVLSd+Y1K ZIdDaoq6Phr2xk670Ul/pqyCMVNmDZjbe3p/p7JDL0L3xJEnN0KaPw4VNhpqa6Z+Gssl Re2g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697591414; x=1698196214; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=E16mHWskjTK/3B68Q/Af3Teg1/R8lnVGjDiVWL3Gi8c=; b=d20C1AMwBx7P3g4IMT23IdhxPYgto9hzLmfQ9a+6dHLTgkDOU0xcVorhQqJxr4F8X/ UjHp2yGPK+VD+9CyLBjFWvrxKtNwmsnbXVaz4+RXElhdZP9DKWWUHzH6mf6ZFqAvbM8V MiGvcyoabXtog7MWc6usJQN1r8PRaVTHeilLHWL+uDoUbktQq/zBGvWli9JbTV4GU+CA UE8+dyc54RFfSXFPtEFJiRuPBohetENAZWy2oJqZf8TSw/lx5XfaCw09eGr7viJd91S5 x95sI2gkmOkpYIOmmeKhE5G+uarPRS/62z3PmIn7hVjppzagUfOoxqVeVTcSxtq9qjGR Qhjw== X-Gm-Message-State: AOJu0YyoIcgJ6TP/tvjXneLn1lFEfjKrRzVMHtsm6kkhnfch1vfltI8w Hsp3Fu/JycMBc5LPK1ZDBWgjJmMP8NY= X-Google-Smtp-Source: AGHT+IGHyYI6m11j74GgAMpc6cp+2vjYXNqQ9yFJFAolNqis+S4xnhwYV0x/iBUJz9i94LnYDn3tHaUP2g4= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:902:ab54:b0:1ca:7295:8127 with SMTP id ij20-20020a170902ab5400b001ca72958127mr78911plb.13.1697591413896; Tue, 17 Oct 2023 18:10:13 -0700 (PDT) Date: Tue, 17 Oct 2023 18:10:12 -0700 In-Reply-To: <20231016184737.1027930-1-michael.roth@amd.com> Mime-Version: 1.0 References: <20231016184737.1027930-1-michael.roth@amd.com> Message-ID: Subject: Re: [PATCH gmem] KVM: selftests: Fix gmem conversion tests for multiple vCPUs From: Sean Christopherson To: Michael Roth Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, vannapurve@google.com Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 16, 2023, Michael Roth wrote: > Currently the private_mem_conversions_test crashes if invoked with the > -n option without also specifying multiple memslots via -m. Totally a PEBKAC, not a bug ;-) > This is because the current implementation assumes -m is specified and > always sets up the per-vCPU memory with a dedicated memslot for each > vCPU. When -m is not specified, the test skips setting up > memslots/memory for secondary vCPUs. > > The current code does seem to try to handle using a single memslot for > multiple vCPUs in some places, e.g. the call-site, but > test_mem_conversions() is missing the important bit of sizing the single > memslot appropriately to handle all the per-vCPU memory. Implement that > handling. > > Signed-off-by: Michael Roth > --- > .../kvm/x86_64/private_mem_conversions_test.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/tools/testing/selftests/kvm/x86_64/private_mem_conversions_test.c b/tools/testing/selftests/kvm/x86_64/private_mem_conversions_test.c > index c04e7d61a585..5eb693fead33 100644 > --- a/tools/testing/selftests/kvm/x86_64/private_mem_conversions_test.c > +++ b/tools/testing/selftests/kvm/x86_64/private_mem_conversions_test.c > @@ -388,10 +388,14 @@ static void test_mem_conversions(enum vm_mem_backing_src_type src_type, uint32_t > gmem_flags = 0; > memfd = vm_create_guest_memfd(vm, memfd_size, gmem_flags); > > - for (i = 0; i < nr_memslots; i++) > - vm_mem_add(vm, src_type, BASE_DATA_GPA + size * i, > - BASE_DATA_SLOT + i, size / vm->page_size, > - KVM_MEM_PRIVATE, memfd, size * i); > + if (nr_memslots == 1) > + vm_mem_add(vm, src_type, BASE_DATA_GPA, BASE_DATA_SLOT, > + memfd_size / vm->page_size, KVM_MEM_PRIVATE, memfd, 0); > + else > + for (i = 0; i < nr_memslots; i++) The if-else needs curly braces. > + vm_mem_add(vm, src_type, BASE_DATA_GPA + size * i, > + BASE_DATA_SLOT + i, size / vm->page_size, > + KVM_MEM_PRIVATE, memfd, size * i); But I think that's a moot point, because isn't it easier to do this? diff --git a/tools/testing/selftests/kvm/x86_64/private_mem_conversions_test.c b/tools/testing/selftests/kvm/x86_64/private_mem_conversions_test.c index c04e7d61a585..c99073098f98 100644 --- a/tools/testing/selftests/kvm/x86_64/private_mem_conversions_test.c +++ b/tools/testing/selftests/kvm/x86_64/private_mem_conversions_test.c @@ -367,6 +367,7 @@ static void test_mem_conversions(enum vm_mem_backing_src_type src_type, uint32_t */ const size_t size = align_up(PER_CPU_DATA_SIZE, get_backing_src_pagesz(src_type)); const size_t memfd_size = size * nr_vcpus; + const size_t slot_size = memfd_size / nr_memslots; struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; pthread_t threads[KVM_MAX_VCPUS]; uint64_t gmem_flags; @@ -390,7 +391,7 @@ static void test_mem_conversions(enum vm_mem_backing_src_type src_type, uint32_t for (i = 0; i < nr_memslots; i++) vm_mem_add(vm, src_type, BASE_DATA_GPA + size * i, - BASE_DATA_SLOT + i, size / vm->page_size, + BASE_DATA_SLOT + i, slot_size / vm->page_size, KVM_MEM_PRIVATE, memfd, size * i); for (i = 0; i < nr_vcpus; i++) {