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Message-ID: <38981112-9091-46d4-a815-8a5f47e15bb2@linux.ibm.com>
Date: Thu, 7 Mar 2024 17:32:09 -0500
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Subject: Re: [PATCH 0/2] Preserve TPM log across kexec
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To: Rob Herring <robh@kernel.org>
Cc: mpe@ellerman.id.au, linux-integrity@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
        jarkko@kernel.org, rnsastry@linux.ibm.com, peterhuewe@gmx.de,
        viparash@in.ibm.com
References: <20240306155511.974517-1-stefanb@linux.ibm.com>
 <b6f74cd0-d1c8-4a6f-a05d-364595c5b079@linux.ibm.com>
 <20240307214245.GA3110385-robh@kernel.org>
From: Stefan Berger <stefanb@linux.ibm.com>
In-Reply-To: <20240307214245.GA3110385-robh@kernel.org>
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On 3/7/24 16:42, Rob Herring wrote:
> On Wed, Mar 06, 2024 at 11:08:20AM -0500, Stefan Berger wrote:
>>
>>
>> On 3/6/24 10:55, Stefan Berger wrote:
>>> This series resolves an issue on PowerVM and KVM on Power where the memory
>>> the TPM log was held in may become inaccessible or corrupted after a kexec
>>> soft reboot. The solution on these two platforms is to store the whole log
>>> in the device tree because the device tree is preserved across a kexec with
>>> either of the two kexec syscalls.
>>>
>> FYI: This was the previous attempt that didn't work with the older kexec
>> syscall: https://lore.kernel.org/lkml/4afde78d-e138-9eee-50e0-dbd32f4dcfe0@linux.ibm.com/T/#m158630d214837e41858b03d4b025e6f96cb8f251
> 
> Doesn't everyone else still need that? Is powerpc the only ones that
Are you referring to the old series with 'that' ? I more or less had to 
abandon it because it wouldn't solve the problem for the old kexec 
syscall, so that's why I am embedding the whole log now in the 
devicetree since the DT is properly carried across the kexec soft reboot 
on PowerVM and KVM for Power. Maybe other platforms will (have to) 
follow, but I don't know.

> care about the old kexec syscall?
> 
> Rob