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Date: Wed, 10 Aug 2016 14:52:01 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Icenowy Zheng <icenowy@aosc.xyz>
Cc: Matt Fleming <matt@codeblueprint.co.uk>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H . Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86/efi-bgrt: remove the check of the version field
Message-ID: <20160810125201.GA9028@gmail.com>
References: <20160809052546.31462-1-icenowy@aosc.xyz>
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* Icenowy Zheng <icenowy@aosc.xyz> wrote:

> Some broken firmwares have a wrongly filled version field in BGRT table.
> (See http://wiki.osdev.org/Broken_UEFI_implementations )
> 
> As we know, these firmwares can also provide correct BGRT image, although
> the table is wrong.
> 
> After removing the check of the version field, the kernel can now extract
> the image correctly, and the information is also correct.
> 
> Tested on a Thinkpad E531 (68854UC).

What's the practical effects of the bug - what problems does a missing 
/sys/firmware/acpi/bgrt/ cause?

I.e. how does the user notice?

Thanks,

	Ingo