From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 76901220F49; Fri, 29 Aug 2025 09:40:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.9 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756460409; cv=none; b=bcY3Lw52VkY7Qd+UN342yRwMR+6dBEi78Q2AlTm6nheUzqkVWmoDkvOxRTuLNFtmCGNkKYLnQI4MCvKc8TSl2BMbXWUUGU73LCghN42vWxAvFCzZOMQMMj7Xr9no2sRF9RMCsVChgtDJIVXe06ArQcXyBzxVYYbrJNqtuyc5YGI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756460409; c=relaxed/simple; bh=Q5/9XsFtWSJoZmQhiX9wJOsCdwjpvOkcJd8IyfdNQNo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=iqkexCHnpIOw4flz4UpS3UX6PGMLEAp/+YKpMA4IL2mV6ptA86+75dGkNnkueCe7dNnhnkjiWCx7HcR1nKDLxRHg75umM/n1YHGJ6Z5xbWaRL3R3gmx33yWZ4RaXI2nwFDYWnvDLpo/yrtM4h0NLW7m80UGB7WwjBxxjww0H8og= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=W0hLJHgY; arc=none smtp.client-ip=192.198.163.9 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="W0hLJHgY" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1756460408; x=1787996408; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=Q5/9XsFtWSJoZmQhiX9wJOsCdwjpvOkcJd8IyfdNQNo=; b=W0hLJHgYy4OZyc/vselz2HcdJs7/n2pO5JDN6JY5RbB7GUrbclePLTjG v/G1MR8De7hDgPoZ8j/Dv2pdgW1cC/uFw9BxuXk6fakgkeR/VPIrznZLK uEjv5UZwHkHiOWibBfrQk1uXLObKR3c1vlulI23KZeniXG/N3Z88gK4aK kX6HhYlLAitRLuFHE+vvlYZZreo04RrxdI0/Tt0+z3LrnjtZzM5IZnGaB O99c3Bk6bGhJJOcOrRoPuljsx8ovjFkntlLrNJ0qCmZTlHAaOBJxVrrwJ rxKpx6Ax+eKSWF8pNX4gwRrQVBHPENwFRuaAPmsdSqMNuUriBZGxdRESv g==; X-CSE-ConnectionGUID: OTcI6THtQ6eo4+vfVb11ew== X-CSE-MsgGUID: R0IPGc9fRtqocktSJSxGPA== X-IronPort-AV: E=McAfee;i="6800,10657,11536"; a="69452300" X-IronPort-AV: E=Sophos;i="6.18,221,1751266800"; d="scan'208";a="69452300" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Aug 2025 02:40:08 -0700 X-CSE-ConnectionGUID: k9vGSEupRdW+j1M1Z0AHBA== X-CSE-MsgGUID: Aq0UkuUZQo23z76f+3dUug== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,221,1751266800"; d="scan'208";a="175636874" Received: from unknown (HELO [10.238.0.107]) ([10.238.0.107]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Aug 2025 02:40:04 -0700 Message-ID: <506f90ed-ff2b-49f9-b1c3-4fb84577dbee@linux.intel.com> Date: Fri, 29 Aug 2025 17:40:01 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH v2 06/18] KVM: TDX: Return -EIO, not -EINVAL, on a KVM_BUG_ON() condition To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Ira Weiny , Kai Huang , Michael Roth , Yan Zhao , Vishal Annapurve , Rick Edgecombe , Ackerley Tng References: <20250829000618.351013-1-seanjc@google.com> <20250829000618.351013-7-seanjc@google.com> Content-Language: en-US From: Binbin Wu In-Reply-To: <20250829000618.351013-7-seanjc@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 8/29/2025 8:06 AM, Sean Christopherson wrote: > Return -EIO when a KVM_BUG_ON() is tripped, as KVM's ABI is to return -EIO > when a VM has been killed due to a KVM bug, not -EINVAL. Note, many (all?) > of the affected paths never propagate the error code to userspace, i.e. > this is about internal consistency more than anything else. > > Signed-off-by: Sean Christopherson Reviewed-by: Binbin Wu > --- > arch/x86/kvm/vmx/tdx.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c > index f24f8635b433..50a9d81dad53 100644 > --- a/arch/x86/kvm/vmx/tdx.c > +++ b/arch/x86/kvm/vmx/tdx.c > @@ -1624,7 +1624,7 @@ static int tdx_mem_page_record_premap_cnt(struct kvm *kvm, gfn_t gfn, > struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); > > if (KVM_BUG_ON(kvm->arch.pre_fault_allowed, kvm)) > - return -EINVAL; > + return -EIO; > > /* nr_premapped will be decreased when tdh_mem_page_add() is called. */ > atomic64_inc(&kvm_tdx->nr_premapped); > @@ -1638,7 +1638,7 @@ static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn, > > /* TODO: handle large pages. */ > if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm)) > - return -EINVAL; > + return -EIO; > > /* > * Read 'pre_fault_allowed' before 'kvm_tdx->state'; see matching > @@ -1661,10 +1661,10 @@ static int tdx_sept_drop_private_spte(struct kvm *kvm, gfn_t gfn, > > /* TODO: handle large pages. */ > if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm)) > - return -EINVAL; > + return -EIO; > > if (KVM_BUG_ON(!is_hkid_assigned(kvm_tdx), kvm)) > - return -EINVAL; > + return -EIO; > > /* > * When zapping private page, write lock is held. So no race condition > @@ -1849,7 +1849,7 @@ static int tdx_sept_free_private_spt(struct kvm *kvm, gfn_t gfn, > * and slot move/deletion. > */ > if (KVM_BUG_ON(is_hkid_assigned(kvm_tdx), kvm)) > - return -EINVAL; > + return -EIO; > > /* > * The HKID assigned to this TD was already freed and cache was > @@ -1870,7 +1870,7 @@ static int tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn, > * there can't be anything populated in the private EPT. > */ > if (KVM_BUG_ON(!is_hkid_assigned(to_kvm_tdx(kvm)), kvm)) > - return -EINVAL; > + return -EIO; > > ret = tdx_sept_zap_private_spte(kvm, gfn, level, page); > if (ret <= 0)