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 A4C20C433F5 for ; Wed, 5 Jan 2022 11:55:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235642AbiAELy7 (ORCPT ); Wed, 5 Jan 2022 06:54:59 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:41537 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231766AbiAELy6 (ORCPT ); Wed, 5 Jan 2022 06:54:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1641383697; 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=aAoXt55k6bjaDtUUwkzXgKzyGKHY2KEKPJyhFtkoMeg=; b=JPWNZ7A9Sc4iTD0KLjHkFi/0dd2QP9B5OKkBplXjpgnZRiZqkfVVJu9Dt1MWpj5xySMtfN qB7coaHHLw06azMY/5EjgUpoFzEEDOYUUNMLsquGueW7NtBABcr2vjFafaijhPh09PkWYS pWAMqdc+HmbvO358nw5Qxmy0dQL7fvk= Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-439-KkTyp4f-P46TOSzUzRhI3A-1; Wed, 05 Jan 2022 06:54:56 -0500 X-MC-Unique: KkTyp4f-P46TOSzUzRhI3A-1 Received: by mail-ed1-f72.google.com with SMTP id r8-20020a05640251c800b003f9a52daa3fso4956615edd.22 for ; Wed, 05 Jan 2022 03:54:56 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=aAoXt55k6bjaDtUUwkzXgKzyGKHY2KEKPJyhFtkoMeg=; b=sPA5lt4Ckr18A+T/kISslbv44n1/ClKb4iaTnzDvhJrNoMgi9soLp3Yc0zoQNb+98A qxQh/p0W+RSXi/06WG3Z8XQ7V2lrmlpu6KB5ScfaFeYwUmX+ui10ZB6omooaCJ8frsju 4CkgPXGiMyHK338+jn8snrJ6uVHS4k63XdXPJMKo36pHIeLv0sNRxj2SFD5RmiyZ1RSS NU5GQ5TWVr264wluU81whC9K5GoiQNnjzAgGkDpJ1tJshKxv446a8LZxPdWxBLyjXhVK AaK4gsy/2qPFHRTujuOLOYFI+qYY7FHU7nKZNL3HY+kVyLtRs/jQuIMHj4pUQ3FOXhD7 A10Q== X-Gm-Message-State: AOAM533WEsDL28ZdgjcuBl+SyMFEAW6YAp1OkbxijNJFLcx5w8XqtEBB U9uP+CY3l0CMJZwIIjorOna+yUbPJhzamGJeog0QGyOJWQ9b9tm8u5Q5BE2IFtqXuRUmsnK7TPz oppbJ36L+lJe+x9wpcXG5nWpF X-Received: by 2002:a05:6402:ca6:: with SMTP id cn6mr31077592edb.134.1641383695521; Wed, 05 Jan 2022 03:54:55 -0800 (PST) X-Google-Smtp-Source: ABdhPJyLThERT6lJIyl3ORC8aXUxR59uN40IfnEPIcXx69NdeTRY4dRecmfZ19cwhwWx4EdNIOKePw== X-Received: by 2002:a05:6402:ca6:: with SMTP id cn6mr31077566edb.134.1641383695299; Wed, 05 Jan 2022 03:54:55 -0800 (PST) Received: from ?IPV6:2001:b07:6468:f312:c8dd:75d4:99ab:290a? ([2001:b07:6468:f312:c8dd:75d4:99ab:290a]) by smtp.googlemail.com with ESMTPSA id h18sm15738239edw.55.2022.01.05.03.54.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 05 Jan 2022 03:54:54 -0800 (PST) Message-ID: Date: Wed, 5 Jan 2022 12:54:47 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.4.0 Subject: Re: [PATCH v2 3/5] KVM: SVM: fix race between interrupt delivery and AVIC inhibition Content-Language: en-US To: Maxim Levitsky , Sean Christopherson Cc: kvm@vger.kernel.org, Jim Mattson , Thomas Gleixner , Joerg Roedel , "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , Vitaly Kuznetsov , Borislav Petkov , linux-kernel@vger.kernel.org, Dave Hansen , "H. Peter Anvin" , Wanpeng Li , Ingo Molnar References: <20211213104634.199141-1-mlevitsk@redhat.com> <20211213104634.199141-4-mlevitsk@redhat.com> <628ac6d9b16c6b3a2573f717df0d2417df7caddb.camel@redhat.com> From: Paolo Bonzini In-Reply-To: <628ac6d9b16c6b3a2573f717df0d2417df7caddb.camel@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/5/22 12:03, Maxim Levitsky wrote: >> Hmm, my preference would be to keep the "return -1" even though apicv_active must >> be rechecked. That would help highlight that returning "failure" after this point >> is not an option as it would result in kvm_lapic_set_irr() being called twice. > I don't mind either - this will fix the tracepoint I recently added to report the > number of interrupts that were delivered by AVIC/APICv - with this patch, > all of them count as such. Perhaps we can move the tracepoints in the delivery functions. This also makes them more precise in the rare case where apicv_active changes in the middle of the function. Paolo