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Subject: Re: Pstore : Query on using ramoops driver for DDR
To:     "Luck, Tony" <tony.luck@intel.com>,
        lkml <linux-kernel@vger.kernel.org>
Cc:     "keescook@chromium.org" <keescook@chromium.org>,
        Anton Vorontsov <anton@enomsg.org>,
        "ccross@android.com" <ccross@android.com>
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 <e28daeb8a1d74d60a3acb5c582f92123@intel.com>
From:   Mukesh Ojha <mojha@codeaurora.org>
Message-ID: <9a653cf1-ab22-15c1-d021-a7cfe2b78276@codeaurora.org>
Date:   Wed, 10 Feb 2021 21:03:20 +0530
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On 2/10/2021 2:32 AM, Luck, Tony wrote:
>> Can we use existing backend pstore ram driver (fs/pstore/ram.c) for DDR
>> instead of SRAM ?
> The expectation for pstore is that the system will go through a reset when it
> crashes. Most systems do not preserve DDR contents across reset.
>
> to support DDR, If we have a mechanism to copy stored data from DDR to
> external device after the crash.
>> Was the current driver written only to support persistant RAM like SRAM
>> or it can accept further change
> Linux is in a constant state of change :-)
>
> See above about DDR contents.   But if you have a platform that does preserve
> DDR contents until your "mechanism" can copy the pstore buffer, then post
> a patch.

Thanks for the reply

I have posted the patch.

https://lore.kernel.org/patchwork/patch/1378949/

-Mukesh


>

> -Tony