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From:   Thiago Jung Bauermann <bauerman@linux.ibm.com>
To:     Joe Perches <joe@perches.com>
Cc:     Will Deacon <will@kernel.org>,
        Lakshmi Ramasubramanian <nramas@linux.microsoft.com>,
        zohar@linux.ibm.com, robh@kernel.org, takahiro.akashi@linaro.org,
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Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer
In-reply-to: <d6ddcab2f9db25f49e89f37e1cb4f59ad42651e6.camel@perches.com>
Date:   Mon, 01 Feb 2021 15:58:06 -0300
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Joe Perches <joe@perches.com> writes:

> On Thu, 2021-01-28 at 00:52 -0300, Thiago Jung Bauermann wrote:
>> The problem is that this patch implements only part of the suggestion,
>> which isn't useful in itself. So the patch series should either drop
>> this patch or consolidate the FDT allocation between the arches.
>> 
>> I just tested on powernv and pseries platforms and powerpc can use
>> vmalloc for the FDT buffer.
>
> Perhaps more sensible to use kvmalloc/kvfree.

That's true. Converting both arm64 to powerpc to kvmalloc/kvfree is a
good option. I don't think it's that much better though, because
kexec_file_load() is called infrequently and doesn't need to be fast so
the vmalloc() overhead isn't important in practice.

-- 
Thiago Jung Bauermann
IBM Linux Technology Center