From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (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 1A67D3C5845 for ; Thu, 4 Jun 2026 19:58:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780603124; cv=none; b=DuBAQaz9UdkXugu/WwlwsSLWL6tdygH8i3tKpF3pTqUpW2/Jhd+QIANVYXl/J7/ndMGNCPigvEICT83AzKOM0dD87HdyNuot2dolRlsCzabeJgH0io0GGmKOMwqUPk7h6CydVQb06OJrWJwsKhy/k3wunlh0+MQvKhYkYNx39G0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780603124; c=relaxed/simple; bh=Jm7YinvVbSvReMReGzBTNouks1rmhCdB6Y6bhY8JdNI=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=OIkHqBs16fKkt7ETmlGQC/WnpZfXJzHyuWxIodK6DUPDQnYxsD+yCMzCNnQBYqNZzEz5wiDmuiNQ6s/xpR9KB+xs5cJqXaBhlw4MuqEbNYW+QMTJNUw7GRRFhloNiqFiOQXzb52ITVk/+xURYsI8AsHNDxv6tqClER5i9ruXSrs= 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=SQ0+REBE; arc=none smtp.client-ip=209.85.210.201 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="SQ0+REBE" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-8423970cb30so713952b3a.2 for ; Thu, 04 Jun 2026 12:58:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1780603122; x=1781207922; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:from:to:cc:subject:date:message-id :reply-to; bh=J1mTM21TlGmY8X4hPpp3UZLp1x2aaMy6UHN1ZJZs6gs=; b=SQ0+REBEDFWMf3YDE8NyHpnK+uqSIfyCrRXdAPgK6h5PxGMMMwnHQqZPbuCCM/4pQ8 tY/jZOjZ+WsjhUe1dE/Q8bxZLH3HCGbwlee1bvuj8DpJVHihXCcs4obwfFkslIWLRscP dicB+Aeg/f3/AAibPaFAErmkJfzRMkCGuncdBHzf0eM5D8uSIFTM+0u17YL6aq8RY3+0 hN4tn3k7fmOw1M6NTvc1M3TACTgPozAd6aQ5ANAmWZEV4Dh4xiTk/EDpa2p79mBgfR1L tXKK3AzZiuYZG2VvmujTZtHF20v3/Y+/rA50iU5CS17w+/1zVoz29WGRWmWb8TZo7RHm TWRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780603122; x=1781207922; h=content-transfer-encoding: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=J1mTM21TlGmY8X4hPpp3UZLp1x2aaMy6UHN1ZJZs6gs=; b=Ywhqt/NUF+D6mvYwwzipNKJfGZLAf6Fy/hQ2LQVSXPo72+ovU7qS6Zn7hajmXEkL1l pdp7rbTivqDFnx9OicZ7GUSfE1xDEFzzFruBeMnJW0nLJWRUqVXqENzoOODGKfYYs1nA Q4KgB8jCoSFRYKHgL2D44WihaCBKGRLUdYFsq55s7DM2xwP6Nctx0jyvql3irSGtm6zE F7icneK4weTw+ucJaQ5u9aGRblfCfwXjBZEuO/MQq5vGvFTAavUNQzhQ9ZEkmdiMG1dX aKSYfnf0HluvXZUM5HbN8FB2C+vhy4Jee03OorZRdHIuWasZ5Eyq5juwAVEBs2kLaTrI DGQA== X-Forwarded-Encrypted: i=1; AFNElJ9uD+q+nXUpM/1+lghP5ek3NTrZj3KpeND+7ixtOK4+0fE8AXpQ3M3E7dzAEsaPB7c/JLs=@vger.kernel.org X-Gm-Message-State: AOJu0Yxa75zHZrH5Y8by7NDqOxwVNtz3cOKOPu5QmMEdHzVUpwYFy9wJ 1QzMgtK72MQCvppnL/uRkivMC7aib7vSeQhKF+fXDbs5m924C5rv+jkvkrQLy+VRFo6vb43vmMt MKHkjEw== X-Received: from pfbdu7.prod.google.com ([2002:a05:6a00:2b47:b0:838:27b2:c6d]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:808f:b0:838:127d:a167 with SMTP id d2e1a72fcca58-842b0e6bb0bmr189707b3a.16.1780603122098; Thu, 04 Jun 2026 12:58:42 -0700 (PDT) Date: Thu, 4 Jun 2026 12:58:41 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <2fccf35715b5ba8aec5e5708d86ad7015b8d74e6.1718214999.git.reinette.chatre@intel.com> Message-ID: Subject: Re: VMX Preemption Timer appears to be buggy on SKX, CLX, and ICX From: Sean Christopherson To: Jim Mattson Cc: Chao Gao , Reinette Chatre , isaku.yamahata@intel.com, pbonzini@redhat.com, erdemaktas@google.com, vkuznets@redhat.com, vannapurve@google.com, mlevitsk@redhat.com, xiaoyao.li@intel.com, rick.p.edgecombe@intel.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, chenyi.qiang@intel.com, Yosry Ahmed Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Wed, Jun 03, 2026, Jim Mattson wrote: > On Thu, May 14, 2026 at 11:35=E2=80=AFPM Chao Gao wr= ote: > > > > >> EMR158. VMX-Preemption Timer May Expire Earlier With Certain Large T= imer Values > > > > > >I assume the same erratum applies to previous generations as well? > > > > Yes. >=20 > This test still fails on our SKX, CLX, and ICX systems. >=20 > Sean, >=20 > Were you thinking of enforcing a cap on delta_tsc in vmx_set_hv_timer()? Heh, to be honest, I wasn't thinking of a whole lot of nothing. Falling ba= ck to hrtimers does seem like the easiest solution.