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 46FAAC433EF for ; Thu, 9 Dec 2021 06:34:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233168AbhLIGia (ORCPT ); Thu, 9 Dec 2021 01:38:30 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:32062 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229784AbhLIGi3 (ORCPT ); Thu, 9 Dec 2021 01:38:29 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1639031695; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NAU6XM/5sfb4CFHRfz4saGiWORFSzRN4hzYWrV4v2/8=; b=CjhWXwFn/ZIM32BgHya7+RxlhU6J7HYUOTbE5C4KoaRuL3ibVK36smRNHCACEF1kYEkmwz R+JaDRJYXm8UaPSleSkauFtuNtfU/+sR5nFyvjNeamMHZTITeRDo0CrJiCNVcMU+D8hloS 6MjddmUeFO7FYn5WQfuH1AJqof6m+z4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-561-feJooAldO5mMHl8upYj3QQ-1; Thu, 09 Dec 2021 01:34:52 -0500 X-MC-Unique: feJooAldO5mMHl8upYj3QQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id F14E5802928; Thu, 9 Dec 2021 06:34:50 +0000 (UTC) Received: from starship (unknown [10.40.192.24]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0667E19C59; Thu, 9 Dec 2021 06:34:47 +0000 (UTC) Message-ID: <9672bb87b3090bc5534c4255315f62441ff04af7.camel@redhat.com> Subject: Re: [PATCH v3 00/26] KVM: x86: Halt and APICv overhaul From: Maxim Levitsky To: Sean Christopherson Cc: Paolo Bonzini , Joerg Roedel , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Suravee Suthikulpanit , kvm@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Date: Thu, 09 Dec 2021 08:34:46 +0200 In-Reply-To: References: <20211208015236.1616697-1-seanjc@google.com> <39c885fc6455dd0aa2f8643e725422851430f9ec.camel@redhat.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.5 (3.36.5-2.fc32) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2021-12-08 at 23:43 +0000, Sean Christopherson wrote: > On Thu, Dec 09, 2021, Maxim Levitsky wrote: > > > KVM: SVM: Remove unnecessary APICv/AVIC update in vCPU unblocking path > > ... > > > Probably just luck (can't reproduce this anymore) but > > while running some kvm unit tests with this patch series (and few my patches > > for AVIC co-existance which shouldn't affect this) I got this > > > > (warning about is_running already set) > > My best guess would be the above commit that dropped the handling in the unblock > path, but I haven't been able to concoct a scenario where avic_physical_id_cache > can get out of sync with respect to kvm_vcpu_apicv_active(). Same here. It seems like the unit test is beeing killed by a timeout signal, I tried to reproduce that this way but no luck so far. Best regards, Maxim Levitsky > > > Dec 08 22:53:26 amdlaptop kernel: ------------[ cut here ]------------ > > Dec 08 22:53:26 amdlaptop kernel: WARNING: CPU: 3 PID: 72804 at arch/x86/kvm/svm/avic.c:1045 avic_vcpu_load+0xe3/0x100 [kvm_amd] > > Dec 08 22:53:26 amdlaptop kernel: Modules linked in: kvm_amd(O) ccp rng_core kvm(O) irqbypass xt_conntrack ip6table_filter ip6_tables snd_soc_dmic snd_acp3x_> > > Dec 08 22:53:26 amdlaptop kernel: r8169 realtek 8250_pci usbmon nbd fuse autofs4 [last unloaded: rng_core] > > Dec 08 22:53:26 amdlaptop kernel: CPU: 3 PID: 72804 Comm: qemu-system-i38 Tainted: G O 5.16.0-rc4.unstable #6 > > Dec 08 22:53:26 amdlaptop kernel: Hardware name: LENOVO 20UF001CUS/20UF001CUS, BIOS R1CET65W(1.34 ) 06/17/2021 > > Dec 08 22:53:26 amdlaptop kernel: RIP: 0010:avic_vcpu_load+0xe3/0x100 [kvm_amd] > > Dec 08 22:53:26 amdlaptop kernel: Code: 0d 9f e0 85 c0 74 e8 4c 89 f6 4c 89 ff e8 a5 99 f4 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b 5b 41 5c 41 5d 41 5e 41 > > > Dec 08 22:53:26 amdlaptop kernel: RSP: 0018:ffffc9000b17bba8 EFLAGS: 00010247 > > Dec 08 22:53:26 amdlaptop kernel: RAX: 6f63203a756d6571 RBX: ffff888106194740 RCX: ffff88812e7ac000 > > Dec 08 22:53:26 amdlaptop kernel: RDX: ffff8883ff6c0000 RSI: 0000000000000003 RDI: 0000000000000003 > > Dec 08 22:53:26 amdlaptop kernel: RBP: ffffc9000b17bbd0 R08: ffff888106194740 R09: 0000000000000000 > > Dec 08 22:53:26 amdlaptop kernel: R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000003 > > Dec 08 22:53:26 amdlaptop kernel: R13: 0000000000000003 R14: ffff88810023b060 R15: dead000000000100 > > Dec 08 22:53:26 amdlaptop kernel: FS: 0000000000000000(0000) GS:ffff8883ff6c0000(0000) knlGS:0000000000000000 > > Dec 08 22:53:26 amdlaptop kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > Dec 08 22:53:26 amdlaptop kernel: CR2: 00005587e812f958 CR3: 0000000105f31000 CR4: 0000000000350ee0 > > Dec 08 22:53:26 amdlaptop kernel: DR0: 00000000004008da DR1: 0000000000000000 DR2: 0000000000000000 > > Dec 08 22:53:26 amdlaptop kernel: DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > > Dec 08 22:53:26 amdlaptop kernel: Call Trace: > > Dec 08 22:53:26 amdlaptop kernel: > > Dec 08 22:53:26 amdlaptop kernel: svm_vcpu_load+0x56/0x60 [kvm_amd] > > Dec 08 22:53:26 amdlaptop kernel: kvm_arch_vcpu_load+0x32/0x210 [kvm] > > Dec 08 22:53:26 amdlaptop kernel: vcpu_load+0x34/0x40 [kvm] > > Dec 08 22:53:26 amdlaptop kernel: kvm_arch_destroy_vm+0xd4/0x1c0 [kvm] > > Dec 08 22:53:26 amdlaptop kernel: kvm_destroy_vm+0x163/0x250 [kvm] > > Dec 08 22:53:26 amdlaptop kernel: kvm_put_kvm+0x26/0x40 [kvm] > > Dec 08 22:53:26 amdlaptop kernel: kvm_vm_release+0x22/0x30 [kvm] > > Dec 08 22:53:26 amdlaptop kernel: __fput+0x94/0x250 > > Dec 08 22:53:26 amdlaptop kernel: ____fput+0xe/0x10 > > Dec 08 22:53:26 amdlaptop kernel: task_work_run+0x63/0xa0 > > Dec 08 22:53:26 amdlaptop kernel: do_exit+0x358/0xa30 > > Dec 08 22:53:26 amdlaptop kernel: do_group_exit+0x3b/0xa0 > > Dec 08 22:53:26 amdlaptop kernel: get_signal+0x15b/0x880 > > Dec 08 22:53:26 amdlaptop kernel: ? _copy_to_user+0x20/0x30 > > Dec 08 22:53:26 amdlaptop kernel: ? put_timespec64+0x3d/0x60 > > Dec 08 22:53:26 amdlaptop kernel: arch_do_signal_or_restart+0x106/0x740 > > Dec 08 22:53:26 amdlaptop kernel: ? hrtimer_nanosleep+0x9f/0x120 > > Dec 08 22:53:26 amdlaptop kernel: ? __hrtimer_init+0xd0/0xd0 > > Dec 08 22:53:26 amdlaptop kernel: exit_to_user_mode_prepare+0x112/0x1f0 > > Dec 08 22:53:26 amdlaptop kernel: syscall_exit_to_user_mode+0x17/0x40 > > Dec 08 22:53:26 amdlaptop kernel: do_syscall_64+0x42/0x80 > > Dec 08 22:53:26 amdlaptop kernel: entry_SYSCALL_64_after_hwframe+0x44/0xae > > Dec 08 22:53:26 amdlaptop kernel: RIP: 0033:0x7f537abb13b5 > > Dec 08 22:53:26 amdlaptop kernel: Code: Unable to access opcode bytes at RIP 0x7f537abb138b. > > Dec 08 22:53:26 amdlaptop kernel: RSP: 002b:00007f5376a39680 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 > > Dec 08 22:53:26 amdlaptop kernel: RAX: fffffffffffffdfc RBX: 00007f5376a396d0 RCX: 00007f537abb13b5 > > Dec 08 22:53:26 amdlaptop kernel: RDX: 00007f5376a396d0 RSI: 0000000000000000 RDI: 0000000000000000 > > Dec 08 22:53:26 amdlaptop kernel: RBP: 00007f5376a396c0 R08: 0000000000000000 R09: 0000000000000000 > > Dec 08 22:53:26 amdlaptop kernel: R10: 00007f5376a396c0 R11: 0000000000000293 R12: 00007f5376a3b640 > > Dec 08 22:53:26 amdlaptop kernel: R13: 0000000000000002 R14: 00007f537ab66880 R15: 0000000000000000 > > Dec 08 22:53:26 amdlaptop kernel: > > Dec 08 22:53:26 amdlaptop kernel: ---[ end trace 676058aaf29d0267 ]--- > > > > > > I'll post my patches tomorrow, after some more testing. > > > > Best regards, > > Maxim Levitsky > >