From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f202.google.com (mail-pf1-f202.google.com [209.85.210.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DAAF615E1EA for ; Wed, 24 Apr 2024 16:13:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713975210; cv=none; b=cabpaz3Jqa+sBahUqHR/8/Z7a4SeKaIpv4t38ZwPGa0zpuXy9EkqldsWl9YsAjvV3EG7HlyJmV5XSkfHFRiWNSnA8riSa9sfT92vwm5vC4EBvL/h1ahlU8oRrJ4ukCAWcA2SlvhVi4XBvsUy20ONx7ghPT07vvzH6ZC7kGIaEh0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713975210; c=relaxed/simple; bh=LWAdr7sNhwS/CNPenio+nMszXGBrLvqRUUDAm9TzMRQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=jxkp8oRbqQ5uTPdAezHPG4iw5mojCOe9ngKUnqtRg7ZJ+aLqEZdCZWrgyMa3/EFZu1zBJWlyA9yL4bGLguLF1l5Yf4aGs3HjyxwemDrObzlJtLn5xx66E41VRF7g/Ml6Gg6oB3eSDTgmoRCRMDwlZ0h3FopN1T0MCqzd06GW4cY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=hPjtlIT6; arc=none smtp.client-ip=209.85.210.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="hPjtlIT6" Received: by mail-pf1-f202.google.com with SMTP id d2e1a72fcca58-6ed4298be66so59446b3a.0 for ; Wed, 24 Apr 2024 09:13:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1713975208; x=1714580008; 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=PaA4wyLmEeZNOg80inX0PuP1bfRa+x1yCphxcXdPVro=; b=hPjtlIT6PgLW+bzEXKypv38tBnheBFqHe95iWB3Fr0JsxB1302SuLFz+Fd780z6y8+ N7V1YLrkvBtRcYnkgjWM3rIW69ClIgB0+EHBbEXp8Z+6PqSwD/9OlA6Z7MjY9+jq6jgk GzjDtHSSgOiUroBWFgTkDjHihzvirZDiPXDaTo5yOHHuDhMZ/ug3Gn+wHImqP39z9MLl vcA3CdjtKAzPIMowa0kZLwGHRDDdVOe9nsgX5JsB4oFS3QGj82echJEZ5sLVVpF+wTr8 AF3ZtNfP72Hsfb66ox4Dqifs0WCOI9JUF1PlDoyZ1bJvDuR70sVuZMRh+uq/YqQvPglF gyxQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713975208; x=1714580008; 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=PaA4wyLmEeZNOg80inX0PuP1bfRa+x1yCphxcXdPVro=; b=QONKmM8Fh8Ju09y09xGFOa6+nn1DANm1eyesdcyppJ3Lwlo8wOi5lYAjn81ws7Ick0 lNv9U7MY2TVjsiuKA7zy1i6Ot4cePV7UiqD1G7CV2tg/84/ke7quaKsqI0UI+E5/KAUN +boVdmanzXXW/LDow8wfQeJw/bLENxqhXvl+cuBvnN1l9qxc0T5ROebeXE4wT1x92sH2 3qe33Xmxy9lADOHkuWKvlO3WG9X76184RfO95UANi8ibSd4xoXiDPD59SRYaydBHw+9o s/GmvBJHgml4RImue79Z3WqJ5LQabVRj/SFM6azSEGTAynG+LjL4rD6KyWrMSl9zkI08 Ddpw== X-Forwarded-Encrypted: i=1; AJvYcCVQkyZYYBU5GHqzHW3I34tQix7+3UoRPt2GES99ngb1Ijp0VQEgqwYq7WRUeG22DBA89DU2KcjLVBNjHneInTH3gEop X-Gm-Message-State: AOJu0YyeVR8oP2axPeeqqRPUBbvJxYOxUiUJ9iXL0TbS58pywPK6jnvr Z3TEvNLnZLZ6QtbN65lq6vJEmxbZegUt7QHHSkDUClTsKTFPhENbnyCYHDgpHV12qGP6zxfLBTp Sag== X-Google-Smtp-Source: AGHT+IGcH9Ew/i2TenHG22Ht2ZajYli2cHigwOlMHHn2UBTTXvMnBBQr0XVBCFOVW2KZ/Dmr6S2qlvHy+Tc= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a05:6a00:2450:b0:6ed:d14e:a1b9 with SMTP id d16-20020a056a00245000b006edd14ea1b9mr273950pfj.0.1713975208058; Wed, 24 Apr 2024 09:13:28 -0700 (PDT) Date: Wed, 24 Apr 2024 09:13:26 -0700 In-Reply-To: <6fae9b07de98d7f56b903031be4490490042ff90.camel@intel.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <6fae9b07de98d7f56b903031be4490490042ff90.camel@intel.com> Message-ID: Subject: Re: [PATCH V4 0/4] KVM: x86: Make bus clock frequency for vAPIC timer configurable From: Sean Christopherson To: Rick P Edgecombe Cc: "jmattson@google.com" , Chao Gao , "vkuznets@redhat.com" , Vishal Annapurve , Reinette Chatre , Xiaoyao Li , Erdem Aktas , "pbonzini@redhat.com" , "mlevitsk@redhat.com" , Isaku Yamahata , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="us-ascii" On Tue, Apr 16, 2024, Rick P Edgecombe wrote: > On Thu, 2024-03-21 at 09:37 -0700, Reinette Chatre wrote: > > > > Summary > > ------- > > Add KVM_CAP_X86_APIC_BUS_FREQUENCY capability to configure the APIC > > bus clock frequency for APIC timer emulation. > > Allow KVM_ENABLE_CAPABILITY(KVM_CAP_X86_APIC_BUS_FREQUENCY) to set the > > frequency in nanoseconds. When using this capability, the user space > > VMM should configure CPUID leaf 0x15 to advertise the frequency. > > Looks good to me and... > Tested-by: Rick Edgecombe > > The only thing missing is actually integrating it into TDX qemu patches and > testing the resulting TD. I think we are making a fair assumption that the > problem should be resolved based on the analysis, but we have not actually > tested that part. Is that right? Please tell me that Rick is wrong, and that this actually has been tested with a TDX guest. I don't care _who_ tested it, or with what VMM it has been tested, but _someone_ needs to verify that this actually fixes the TDX issue.