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From: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= <f4bug@amsat.org>
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Subject: Re: [Qemu-devel] [PATCH v3 2/2] loader: Fix 64-bit misaligned
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To: Richard Henderson <richard.henderson@linaro.org>, David Gibson <david@gibson.dropbear.id.au>, Peter Maydell <peter.maydell@linaro.org>
Cc: =?UTF-8?Q?Marc-Andr=c3=a9_Lureau?= <marcandre.lureau@redhat.com>, Paul Burton <paul.burton@mips.com>, qemu-devel@nongnu.org

On 04/23/2018 02:34 PM, Richard Henderson wrote:
> On 04/23/2018 06:25 AM, Philippe Mathieu-Daudé wrote:
>> Assuming the base of the fdt is aligned, a 32-bit property returns
>> a 32-bit aligned pointer...
> ...
>>      case 4:
>> -        *addr = fdt32_to_cpu(*(fdt32_t *)prop);
>> +        *addr = fdt32_to_cpu(ldl_he_p(prop));
>>          return 0;
> 
> So why are you changing the 32-bit case?

First to not assume base fdt is always 32-bit aligned,
second to keep calls similar and avoid someone use *(fdt64_t *) similar
to the 32-bit property. But this is avoidable with a simple comment
about why we have to use ldq_he_p().