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Subject: Re: efi_enabled(EFI_PARAVIRT) use
To: Matt Fleming <matt@codeblueprint.co.uk>
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Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Stefano Stabellini <sstabellini@kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        "Luis R. Rodriguez" <mcgrof@kernel.org>,
        Jeremy Fitzhardinge <jeremy@goop.org>,
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        Xen Devel <Xen-devel@lists.xensource.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>, linux-next@vger.kernel.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Borislav Petkov <bp@alien8.de>
From: Shannon Zhao <shannon.zhao@linaro.org>
Message-ID: <57261483.10500@linaro.org>
Date: Sun, 1 May 2016 22:36:51 +0800
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On 2016年05月01日 21:26, Matt Fleming wrote:
> On Sun, 01 May, at 11:24:18AM, Shannon Zhao wrote:
>> Because the UEFI params for Dom0 are located under /hypervisor/uefi node
>> instead of /chosen. So it needs to check whether it's a Dom0 then search
>> and parse different node with different params arrays.
>  
> Why can't you search both nodes? 
Before searching, it needs to decide which uefi params array should be
passed to of_scan_flat_dt().

> Would you ever expect to see both for
> a Dom0 kernel?
> 
>> So it still needs add another check to firstly parse the fdt to see if
>> there is "xen,uefi-system-table" under /hypervisor/uefi node, right? I
>> think it's a bit redundant compared with xen_initial_domain().
> 
> Sometimes you really do need to check xen_initial_domain(), but I do
> not think this is such a case. And if we can get by without adding
> that check, the code will be better for it.
> 
So is there any other way you suggest?

Thanks,
-- 
Shannon