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Date:   Tue, 13 Jun 2023 16:27:30 +0000
From:   Mostafa Saleh <smostafa@google.com>
To:     Oliver Upton <oliver.upton@linux.dev>
Cc:     kvmarm@lists.linux.dev, maz@kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        suzuki.poulose@arm.com, kaleshsingh@google.com, tabba@google.com,
        yuzenghui@huawei.com, catalin.marinas@arm.com, james.morse@arm.com,
        will@kernel.org
Subject: Re: [PATCH] KVM: arm64: Use different pointer authentication keys
 for pKVM
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References: <20230516141531.791492-1-smostafa@google.com>
 <168665854178.2681974.13725664134174024912.b4-ty@linux.dev>
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Hi Oliver,

On Tue, Jun 13, 2023 at 12:16:02PM +0000, Oliver Upton wrote:
> On Tue, 16 May 2023 14:15:31 +0000, Mostafa Saleh wrote:
> > When the kernel is compiled with CONFIG_ARM64_PTR_AUTH_KERNEL, it
> > uses Armv8.3-Pauth for return address protection for the kernel code
> > including nvhe code in EL2.
> > 
> > Same keys are used in both kernel(EL1) and nvhe code(EL2), this is
> > fine for nvhe but not when running in protected mode(pKVM) as the host
> > can't be trusted.
> > 
> > [...]
> 
> Applied to kvmarm/next, thanks!
> 
> [1/1] KVM: arm64: Use different pointer authentication keys for pKVM
>       https://git.kernel.org/kvmarm/kvmarm/c/fb737685beee
> 
> --

Thanks! I did more testing and I found a bug in this patch.

It seems there is another entry point for the kenrel where pauth was
not handled properly "kvm_host_psci_cpu_entry", I will investigate this
further and send V2.

Sorry for the inconvenience!

Thanks,
Mostafa