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Date:   Mon, 31 Oct 2022 12:27:19 -0700
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Subject: Re: [PATCH 1/2] x86/tdx: Extract GET_INFO call from get_cc_mask()
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To:     "Kirill A. Shutemov" <kirill@shutemov.name>,
        Dave Hansen <dave.hansen@intel.com>
Cc:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
        luto@kernel.org, peterz@infradead.org,
        sathyanarayanan.kuppuswamy@linux.intel.com,
        dan.j.williams@intel.com, david@redhat.com, hpa@zytor.com,
        seanjc@google.com, thomas.lendacky@amd.com,
        elena.reshetova@intel.com, x86@kernel.org,
        linux-kernel@vger.kernel.org
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From:   Andi Kleen <ak@linux.intel.com>
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sted-by's would be appreciated.
> One thing that I must bring up is that it seems that there's no way to get
> the panic message to user. I tried to convinced myself that it is qemu
> misconfiguration on my part or some race, but no: it is just too early for
> earlyprintk.
>
> We only get earlyprintk working after parse_early_options() which happens
> well after tdx_early_init().
>
> Moving panic() after earlyprintk working is not good idea as it exposes
> kernel more: by the time we already have full #VE handler.


It should be fine to move since there is no user land at this point (the 
attack requires user land)


>
> We can move it earlier into decompresser which has different earlyprintk
> implementation. Not sure if it worth this. What do you think?

That would make uncompressed kernels unsafe.

-Andi