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Date: Tue, 20 May 2025 15:58:46 +0100
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Subject: Re: [PATCH v8 20/43] arm64: RME: Runtime faulting of memory
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From: Suzuki K Poulose <suzuki.poulose@arm.com>
To: Steven Price <steven.price@arm.com>, kvm@vger.kernel.org,
 kvmarm@lists.linux.dev
Cc: Catalin Marinas <catalin.marinas@arm.com>, Marc Zyngier <maz@kernel.org>,
 Will Deacon <will@kernel.org>, James Morse <james.morse@arm.com>,
 Oliver Upton <oliver.upton@linux.dev>, Zenghui Yu <yuzenghui@huawei.com>,
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 <alexandru.elisei@arm.com>, Christoffer Dall <christoffer.dall@arm.com>,
 Fuad Tabba <tabba@google.com>, linux-coco@lists.linux.dev,
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 Gavin Shan <gshan@redhat.com>, Shanker Donthineni <sdonthineni@nvidia.com>,
 Alper Gun <alpergun@google.com>, "Aneesh Kumar K . V"
 <aneesh.kumar@kernel.org>
References: <20250416134208.383984-1-steven.price@arm.com>
 <20250416134208.383984-21-steven.price@arm.com>
 <3a04995a-524c-4d07-8c8b-82930f9bca72@arm.com>
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On 19/05/2025 18:35, Suzuki K Poulose wrote:
> Hi Steven
> 
> On 16/04/2025 14:41, Steven Price wrote:
>> At runtime if the realm guest accesses memory which hasn't yet been
>> mapped then KVM needs to either populate the region or fault the guest.
>>
>> For memory in the lower (protected) region of IPA a fresh page is
>> provided to the RMM which will zero the contents. For memory in the
>> upper (shared) region of IPA, the memory from the memslot is mapped
>> into the realm VM non secure.
>>
>> Signed-off-by: Steven Price <steven.price@arm.com>

>> +    } else {
>> +        map_level = 3;
>> +        map_size = RMM_PAGE_SIZE;
>> +    }
>> +
>> +    for (offset = 0; offset < size; offset += map_size) {
>> +        /*
>> +         * realm_map_ipa() enforces that the memory is writable,
> 
> The function names seems to be obsolete, please fix.

Doh, it is in arch/arm64/kvm/mmu.c, please ignore this comment.

Suzuki