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Message-ID: <483f9e1e-7d01-5f06-3bfa-3788d2554724@linux.intel.com>
Date:   Wed, 27 Sep 2023 13:19:29 +0800
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Subject: Re: [RFC PATCH v12 11/33] KVM: Introduce per-page memory attributes
To:     Sean Christopherson <seanjc@google.com>
Cc:     kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        kvmarm@lists.linux.dev, linux-mips@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org,
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        linux-mm@kvack.org, linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
        Marc Zyngier <maz@kernel.org>,
        Oliver Upton <oliver.upton@linux.dev>,
        Huacai Chen <chenhuacai@kernel.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Anup Patel <anup@brainfault.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Paul Moore <paul@paul-moore.com>,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        Chao Peng <chao.p.peng@linux.intel.com>,
        Fuad Tabba <tabba@google.com>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        Anish Moorthy <amoorthy@google.com>,
        Yu Zhang <yu.c.zhang@linux.intel.com>,
        Isaku Yamahata <isaku.yamahata@intel.com>,
        Xu Yilun <yilun.xu@intel.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Vishal Annapurve <vannapurve@google.com>,
        Ackerley Tng <ackerleytng@google.com>,
        Maciej Szmigiero <mail@maciej.szmigiero.name>,
        David Hildenbrand <david@redhat.com>,
        Quentin Perret <qperret@google.com>,
        Michael Roth <michael.roth@amd.com>,
        Wang <wei.w.wang@intel.com>,
        Liam Merwick <liam.merwick@oracle.com>,
        Isaku Yamahata <isaku.yamahata@gmail.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
References: <20230914015531.1419405-1-seanjc@google.com>
 <20230914015531.1419405-12-seanjc@google.com>
 <d66795f8-e524-2912-4b71-92ca4ffe8807@linux.intel.com>
 <ZQteNbPfx6P3r6B8@google.com>
From:   Binbin Wu <binbin.wu@linux.intel.com>
In-Reply-To: <ZQteNbPfx6P3r6B8@google.com>
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On 9/21/2023 5:03 AM, Sean Christopherson wrote:
> On Mon, Sep 18, 2023, Binbin Wu wrote:
>>
>> On 9/14/2023 9:55 AM, Sean Christopherson wrote:
>>> From: Chao Peng <chao.p.peng@linux.intel.com>
>> [...]
>>> +#ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES
>>> +/*
>>> + * Returns true if _all_ gfns in the range [@start, @end) have attributes
>>> + * matching @attrs.
>>> + */
>>> +bool kvm_range_has_memory_attributes(struct kvm *kvm, gfn_t start, gfn_t end,
>>> +				     unsigned long attrs)
>>> +{
>>> +	XA_STATE(xas, &kvm->mem_attr_array, start);
>>> +	unsigned long index;
>>> +	bool has_attrs;
>>> +	void *entry;
>>> +
>>> +	rcu_read_lock();
>>> +
>>> +	if (!attrs) {
>>> +		has_attrs = !xas_find(&xas, end);
>> IIUIC, xas_find() is inclusive for "end", so here should be "end - 1" ?
> Yes, that does appear to be the case.  Inclusive vs. exclusive on gfn ranges has
> is the bane of my existence.

Seems this one is not included in the "KVM: guest_memfd fixes" patch series?
https://lore.kernel.org/kvm/20230921203331.3746712-1-seanjc@google.com/