Date:   Wed, 15 Mar 2023 09:21:34 -0700
In-Reply-To: <ZBGRJaV3tDTVyE/q@yzhao56-desk.sh.intel.com>
Mime-Version: 1.0
References: <20230311002258.852397-1-seanjc@google.com> <20230311002258.852397-21-seanjc@google.com>
 <ZBGRJaV3tDTVyE/q@yzhao56-desk.sh.intel.com>
Message-ID: <ZBHwjm2heYeE40xl@google.com>
Subject: Re: [PATCH v2 20/27] KVM: x86/mmu: Use page-track notifiers iff there
 are external users
From:   Sean Christopherson <seanjc@google.com>
To:     Yan Zhao <yan.y.zhao@intel.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Zhenyu Wang <zhenyuw@linux.intel.com>,
        Zhi Wang <zhi.a.wang@intel.com>, kvm@vger.kernel.org,
        intel-gvt-dev@lists.freedesktop.org,
        intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        Ben Gardon <bgardon@google.com>
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Precedence: bulk

On Wed, Mar 15, 2023, Yan Zhao wrote:
> Nit: there is a typo in the commit header: "iff" -> "if"
> 
> > -void kvm_page_track_write(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new,
> > -			  int bytes)
> > +void __kvm_page_track_write(struct kvm *kvm, gpa_t gpa, const u8 *new, int bytes)
> Line length is 81 characters. A little longer than 80 :)
> 
> > +static inline bool kvm_page_track_has_external_user(struct kvm *kvm) { return false; }
> This line is also too long.

The 80 character limit is a "soft" limit these days, e.g. checkpatch only complains
if a line is 100+.  In KVM x86, the preferred style is to treat the 80 char limit
as "firm", for lack of a better word.  E.g. let a line run over if it's just a
char or two and there's no other wrapping in the declaration, but don't create long
lines just because checkpatch no longer yells.

There's obviously a fair bit of subjectivity, but the guideline has worked well
so far (hopefully I didn't just jinx us).