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Date:   Mon, 29 Mar 2021 07:18:50 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Dmitry Osipenko <digetx@gmail.com>
Cc:     Jens Axboe <axboe@kernel.dk>,
        Thierry Reding <thierry.reding@gmail.com>,
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Subject: Re: [PATCH v1 3/3] partitions/efi: Support gpt_sector parameter
 needed by NVIDIA Tegra devices
Message-ID: <20210329061850.GA258398@infradead.org>
References: <20210327212100.3834-1-digetx@gmail.com>
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On Sun, Mar 28, 2021 at 12:21:00AM +0300, Dmitry Osipenko wrote:
> All NVIDIA Tegra20..124 Android devices use proprietary bootloader
> which supplies the gpt_sector=<sector> kernel cmdline parameter that
> should be used for looking up the EFI partition table on internal EMMC
> storage.  If the kernel cmdline parameter isn't supplied, then the
> partition is expected to be placed around the last but one sector of EMMC.
> 
> Apparently this was done in order to hide the PT from a usual userspace
> tools since EFI entry exists only for compatibility with a Linux kernel,

That's weird, because nothin in Linux relies in EFI partition tables.

> while a custom proprietary partition table is what is really used by
> these Android devices, thus these tools may corrupt the real PT, making
> device unbootable and very difficult to restore.
> 
> Add support for the gpt_sector cmdline parameter which will be used
> for finding EFI entry on internal EMMC storage of NVIDIA Tegra20+ devices.

Didn't we plan to just support the actual partition table format insted?