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Date:   Mon, 30 Oct 2023 18:11:39 +0100
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Subject: Re: [PATCH v13 10/35] KVM: Add a dedicated mmu_notifier flag for
 reclaiming freed memory
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To:     Sean Christopherson <seanjc@google.com>,
        Marc Zyngier <maz@kernel.org>,
        Oliver Upton <oliver.upton@linux.dev>,
        Huacai Chen <chenhuacai@kernel.org>,
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        Albert Ou <aou@eecs.berkeley.edu>,
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        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
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Cc:     kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
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        =?UTF-8?B?TWlja2HDq2wgU2FsYcO8?= =?UTF-8?Q?n?= <mic@digikod.net>,
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References: <20231027182217.3615211-1-seanjc@google.com>
 <20231027182217.3615211-11-seanjc@google.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
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On 10/27/23 20:21, Sean Christopherson wrote:
> Handle AMD SEV's kvm_arch_guest_memory_reclaimed() hook by having
> __kvm_handle_hva_range() return whether or not an overlapping memslot
> was found, i.e. mmu_lock was acquired.  Using the .on_unlock() hook
> works, but kvm_arch_guest_memory_reclaimed() needs to run after dropping
> mmu_lock, which makes .on_lock() and .on_unlock() asymmetrical.
> 
> Use a small struct to return the tuple of the notifier-specific return,
> plus whether or not overlap was found.  Because the iteration helpers are
> __always_inlined, practically speaking, the struct will never actually be
> returned from a function call (not to mention the size of the struct will
> be two bytes in practice).

Could have been split in two patches, but it's fine anyway.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>

Paolo