From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 033E418028 for ; Thu, 12 Sep 2024 13:58:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726149531; cv=none; b=Sn3ExqS64qqyAF7lZ7HU3qOvzbCjwOBxJfFy6jQaJIqBlNzq6mV/KZiWAWxaOt8wW1fYCNOPf4tvRi2nVI0JhQjk8boBHkY0g4GimLN7shVX8gXnhUhNm0NNEUZO2s4fiMqGqT3zMIUzK+/AHHtv8diAACtHJyp1udZsd8T7UUM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726149531; c=relaxed/simple; bh=SeITqANqh8uS/MwUSMMbpOgql+rfNsYyyshPxmsnKYw=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=bR3uptakTSOzYArnSfpW8tce00lKP6ww5WaOcuKnRwDK1KNUJ7+OFup5hisSVqOq5iBhK2JIC8zc2YsN20ArWKyYgAIdSSSMKMaLc6dIg4x6AN/Rsscd6NyQXHBBMsLTuYXgnnSI0tnng2BLQz8B8aAXNXLmXizUv/pb42lq2E4= 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=P2nC27CN; arc=none smtp.client-ip=209.85.214.202 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="P2nC27CN" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-1ff24acb60dso9801355ad.0 for ; Thu, 12 Sep 2024 06:58:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1726149529; x=1726754329; 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=ZK6HVHZn98Hj1qj5vJmB4zUj1ZfRB7+fu+YXBUGUC+g=; b=P2nC27CNjjo+D8hhpSfjI6jvkPYcSuTLvUzo0qwN2s8vz8jWrW5NJOKcCxyqKs1NQ4 B0w3CdF/qRO3+QmeM8L1sA3DC8Y+EUXQrdeFpp7tV1H4M+xGFKXSh0upLlLufRARZ0bP E3R54e4xCJDblKmZb5rEqJnyP7vo7skWIUjZE7fq7OaZlXcQoHRWH0MHrra+tK00DF60 clBNCmkrPoOPuxCg10YfuqXbZadHm0Ig7ptvyhh71sdj7Jwo/U0khRf+RtlSrlPx/vUo 2FswaNixXC8hEP2e0D6+bcV+c2rvjRKxbYTgP5ntO4LLkTM8DCu0QaE80MgO21GTnl64 GJDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726149529; x=1726754329; 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=ZK6HVHZn98Hj1qj5vJmB4zUj1ZfRB7+fu+YXBUGUC+g=; b=WMJY4rr3T09RCwNbDCailfp8snNfaSJeb0/nGGs8qLXa0XMQlngzPNkWDhUyXegVYG K5pUOJaYdm3e1klqIMH533W2dBAYN3CfREjkyBtiH70+tZU7rHo64te8c2nM+mx0cuMa ujELO7TKrHpz2xOPj8HcnW80A6oqZ5SUZiQ3109h9ztNB7ZvaR3WbXbX/9LHqmTnlWnm b9pauCU2vFogHZ26qvn7nZV3v6p1aXIgaKyGVYI8g/DDjExFHVeF5Q7HlnpgHeyqCjqX oA9bxy6gGHXjeNLfxgbtan7ueA8ynJY1mmGGcZAZCsYHrOD8jWSvvOqBHMs7A2B6PdnY CvUw== X-Forwarded-Encrypted: i=1; AJvYcCWbhbgMGsJTjK4251W2NAiFB+OdXi0JQD6QkNUUX+CxvqTh/XAcZn0721K23H4MRnxjYE91EhRVXTxOTUc=@vger.kernel.org X-Gm-Message-State: AOJu0Yy2JXeF+/oYYDSLDJdRjIKzOHcmx+bjXQFZEhXbg0Bu+0lfx/Xf 959xulrUWDqIyOZGyefgxGF46VpbEHM0uDA08SSDGR0VX7rqCpIBHYSlGNq7LFOFqZ9ZrgOn4TP XSA== X-Google-Smtp-Source: AGHT+IFqTdTG4b3Mr7BP/09ZXc+oW/zlXp3T5xgWOLFDE7WfwPK4BdJD+RmItP4d7duZp2TQ8vP7BLIJ0nw= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:903:64e:b0:205:58ee:1567 with SMTP id d9443c01a7336-2074c3ae046mr208235ad.0.1726149529086; Thu, 12 Sep 2024 06:58:49 -0700 (PDT) Date: Thu, 12 Sep 2024 06:58:47 -0700 In-Reply-To: <8761e1b8-4c65-4837-b152-98be86cf220d@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240904030751.117579-1-rick.p.edgecombe@intel.com> <20240904030751.117579-6-rick.p.edgecombe@intel.com> <8761e1b8-4c65-4837-b152-98be86cf220d@intel.com> Message-ID: Subject: Re: [PATCH 05/21] KVM: VMX: Teach EPT violation helper about private mem From: Sean Christopherson To: Kai Huang Cc: Rick Edgecombe , pbonzini@redhat.com, kvm@vger.kernel.org, dmatlack@google.com, isaku.yamahata@gmail.com, yan.y.zhao@intel.com, nik.borisov@suse.com, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="us-ascii" On Thu, Sep 12, 2024, Kai Huang wrote: > > +static inline bool kvm_is_private_gpa(struct kvm *kvm, gpa_t gpa) > > +{ > > + /* For TDX the direct mask is the shared mask. */ > > + return !kvm_is_addr_direct(kvm, gpa); > > +} > > Does this get used in any other places? If no I think we can open code this > in the __vmx_handle_ept_violation(). > > The reason is I think the name kvm_is_private_gpa() is too generic and this > is in the header file. +1, kvm_is_private_gpa() is much too generic. I knew what the code was *supposed* to do, but had to look at the implementation to verify that's actually what it did. > E.g., one can come up with another kvm_is_private_gpa() checking the memory > attributes to tell whether a GPA is private. > > Or we rename it to something like > > __vmx_is_faulting_gpa_private() > ? > > Which clearly says it is checking the *faulting* GPA. I don't think that necessarily solves the problem either, because the reader has to know that the KVM looks at the shared bit. If open coding is undesirable, maybe a very literal name, e.g. vmx_is_shared_bit_set()?