From patchwork Thu Jul 4 16:25:21 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thibault Ferrante X-Patchwork-Id: 1956973 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ubuntu.com (client-ip=185.125.189.65; helo=lists.ubuntu.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=patchwork.ozlabs.org) Received: from lists.ubuntu.com (lists.ubuntu.com [185.125.189.65]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4WFMT91Z6Wz1xpP for ; Fri, 5 Jul 2024 02:25:49 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=lists.ubuntu.com) by lists.ubuntu.com with esmtp (Exim 4.86_2) (envelope-from ) id 1sPPHD-0001n7-NF; Thu, 04 Jul 2024 16:25:43 +0000 Received: from smtp-relay-canonical-0.internal ([10.131.114.83] helo=smtp-relay-canonical-0.canonical.com) by lists.ubuntu.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1sPPH9-0001iD-Ee for kernel-team@lists.ubuntu.com; Thu, 04 Jul 2024 16:25:39 +0000 Received: from Q58-sff.. (2.general.thibf.uk.vpn [10.172.200.120]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-0.canonical.com (Postfix) with ESMTPSA id 37DB93F2E1; Thu, 4 Jul 2024 16:25:39 +0000 (UTC) From: Thibault Ferrante To: kernel-team@lists.ubuntu.com Subject: [SRU][N:intel][PATCH 4/4] KVM: selftests: x86: Prioritize getting max_gfn from GuestPhysBits Date: Thu, 4 Jul 2024 18:25:21 +0200 Message-ID: <20240704162521.3375266-5-thibault.ferrante@canonical.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240704162521.3375266-1-thibault.ferrante@canonical.com> References: <20240704162521.3375266-1-thibault.ferrante@canonical.com> MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Tao Su BugLink: https://bugs.launchpad.net/bugs/2071628 Use the max mappable GPA via GuestPhysBits advertised by KVM to calculate max_gfn. Currently some selftests (e.g. access_tracking_perf_test, dirty_log_test...) add RAM regions close to max_gfn, so guest may access GPA beyond its mappable range and cause infinite loop. Adjust max_gfn in vm_compute_max_gfn() since x86 selftests already overrides vm_compute_max_gfn() specifically to deal with goofy edge cases. Reported-by: Yi Lai Signed-off-by: Tao Su Tested-by: Yi Lai Reviewed-by: Xiaoyao Li Link: https://lore.kernel.org/r/20240513014003.104593-1-tao1.su@linux.intel.com [sean: tweak name, add comment and sanity check] Signed-off-by: Sean Christopherson (cherry picked from commit 980b8bc01938c8bcc9742c1051f64b5f0ed178ac) Signed-off-by: Thibault Ferrante --- .../selftests/kvm/include/x86_64/processor.h | 1 + .../testing/selftests/kvm/lib/x86_64/processor.c | 15 +++++++++++++-- 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index d2534a4a077b..3142eb4f05e3 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -279,6 +279,7 @@ struct kvm_x86_cpu_property { #define X86_PROPERTY_MAX_EXT_LEAF KVM_X86_CPU_PROPERTY(0x80000000, 0, EAX, 0, 31) #define X86_PROPERTY_MAX_PHY_ADDR KVM_X86_CPU_PROPERTY(0x80000008, 0, EAX, 0, 7) #define X86_PROPERTY_MAX_VIRT_ADDR KVM_X86_CPU_PROPERTY(0x80000008, 0, EAX, 8, 15) +#define X86_PROPERTY_GUEST_MAX_PHY_ADDR KVM_X86_CPU_PROPERTY(0x80000008, 0, EAX, 16, 23) #define X86_PROPERTY_SEV_C_BIT KVM_X86_CPU_PROPERTY(0x8000001F, 0, EBX, 0, 5) #define X86_PROPERTY_PHYS_ADDR_REDUCTION KVM_X86_CPU_PROPERTY(0x8000001F, 0, EBX, 6, 11) diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c index 4b7fe7e1e234..832f85dcf269 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c @@ -1278,9 +1278,20 @@ unsigned long vm_compute_max_gfn(struct kvm_vm *vm) { const unsigned long num_ht_pages = 12 << (30 - vm->page_shift); /* 12 GiB */ unsigned long ht_gfn, max_gfn, max_pfn; - uint8_t maxphyaddr; + uint8_t maxphyaddr, guest_maxphyaddr; - max_gfn = (1ULL << (vm->pa_bits - vm->page_shift)) - 1; + /* + * Use "guest MAXPHYADDR" from KVM if it's available. Guest MAXPHYADDR + * enumerates the max _mappable_ GPA, which can be less than the raw + * MAXPHYADDR, e.g. if MAXPHYADDR=52, KVM is using TDP, and the CPU + * doesn't support 5-level TDP. + */ + guest_maxphyaddr = kvm_cpu_property(X86_PROPERTY_GUEST_MAX_PHY_ADDR); + guest_maxphyaddr = guest_maxphyaddr ?: vm->pa_bits; + TEST_ASSERT(guest_maxphyaddr <= vm->pa_bits, + "Guest MAXPHYADDR should never be greater than raw MAXPHYADDR"); + + max_gfn = (1ULL << (guest_maxphyaddr - vm->page_shift)) - 1; /* Avoid reserved HyperTransport region on AMD processors. */ if (!host_cpu_is_amd)