Re: efi_enabled(EFI_PARAVIRT) use

From	Shannon Zhao <shannon.zhao@linaro.org>
Newsgroups	linux.kernel
Subject	Re: efi_enabled(EFI_PARAVIRT) use
Date	2016-05-01 05:30 +0200
Message-ID	<rtQeZ-2mD-5@gated-at.bofh.it> (permalink)
References	(2 earlier) <rte02-4gY-25@gated-at.bofh.it> <rthKi-7Bl-7@gated-at.bofh.it> <rti3F-7N6-69@gated-at.bofh.it> <rtDUt-IU-7@gated-at.bofh.it> <rtJZU-5Hj-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On 2016年05月01日 04:44, Matt Fleming wrote:
>> While I still have a question, in this patch we use
>> > efi_enabled(EFI_PARAVIRT) as a condition to make fdt_find_uefi_params()
>> > and efi_get_fdt_params() execute different ways. So it needs to find a
>> > new condition for that if we need to get rid of EFI_PARAVIRT. One I
>> > think is that xen_initial_domain() check. Is that fine?
> Hmm... why do you actually need to check whether you're running on a
> PV machine in fdt_find_uefi_params()?
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.

> Can't you infer that from the DT
> params you discover?
> 

> I could understand maybe only accepting the "xen,uefi-system-table"
> property if IS_ENABLED(CONFIG_XEN) but surely you don't also need to
> filter based on whether you're booting a PV kernel?
> 
> Let me put it this way: when would you see "xen,uefi-system-table" and
> *not* be booting a PV 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().

Thanks,
-- 
Shannon

Thread

linux-next: manual merge of the xen-tip tree with the tip tree Stephen Rothwell <sfr@canb.auug.org.au> - 2016-04-29 06:30 +0200
  Re: efi_enabled(EFI_PARAVIRT) use Ingo Molnar <mingo@kernel.org> - 2016-04-29 08:40 +0200
    Re: efi_enabled(EFI_PARAVIRT) use Borislav Petkov <bp@alien8.de> - 2016-04-29 10:30 +0200
      Re: efi_enabled(EFI_PARAVIRT) use Matt Fleming <matt@codeblueprint.co.uk> - 2016-04-29 11:30 +0200
    Re: efi_enabled(EFI_PARAVIRT) use Stefano Stabellini <sstabellini@kernel.org> - 2016-04-29 12:40 +0200
      Re: efi_enabled(EFI_PARAVIRT) use Ingo Molnar <mingo@kernel.org> - 2016-04-29 12:50 +0200
      Re: efi_enabled(EFI_PARAVIRT) use Matt Fleming <matt@codeblueprint.co.uk> - 2016-04-29 16:40 +0200
        Re: efi_enabled(EFI_PARAVIRT) use Ard Biesheuvel <ard.biesheuvel@linaro.org> - 2016-04-29 17:00 +0200
          Re: efi_enabled(EFI_PARAVIRT) use Shannon Zhao <shannon.zhao@linaro.org> - 2016-04-30 16:20 +0200
            Re: efi_enabled(EFI_PARAVIRT) use Matt Fleming <matt@codeblueprint.co.uk> - 2016-04-30 22:50 +0200
              Re: efi_enabled(EFI_PARAVIRT) use Shannon Zhao <shannon.zhao@linaro.org> - 2016-05-01 05:30 +0200
                Re: efi_enabled(EFI_PARAVIRT) use Matt Fleming <matt@codeblueprint.co.uk> - 2016-05-01 15:30 +0200
                Re: efi_enabled(EFI_PARAVIRT) use Shannon Zhao <shannon.zhao@linaro.org> - 2016-05-01 16:40 +0200
                Re: efi_enabled(EFI_PARAVIRT) use Matt Fleming <matt@codeblueprint.co.uk> - 2016-05-02 12:50 +0200
                Re: [Xen-devel] efi_enabled(EFI_PARAVIRT) use Shannon Zhao <zhaoshenglong@huawei.com> - 2016-05-03 03:50 +0200
                Re: [Xen-devel] efi_enabled(EFI_PARAVIRT) use Matt Fleming <matt@codeblueprint.co.uk> - 2016-05-04 13:40 +0200
            Re: [Xen-devel] efi_enabled(EFI_PARAVIRT) use Shannon Zhao <zhaoshenglong@huawei.com> - 2016-05-03 11:20 +0200
        Re: efi_enabled(EFI_PARAVIRT) use Stefano Stabellini <sstabellini@kernel.org> - 2016-04-29 17:00 +0200
          Re: efi_enabled(EFI_PARAVIRT) use Stefano Stabellini <sstabellini@kernel.org> - 2016-04-29 17:40 +0200
            Re: efi_enabled(EFI_PARAVIRT) use Shannon Zhao <shannon.zhao@linaro.org> - 2016-04-30 16:10 +0200

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