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Sender: Richard Henderson <rth7680@gmail.com>
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Date: Sat, 24 Apr 2010 17:36:46 -0700
From: Richard Henderson <rth@twiddle.net>
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Subject: [Qemu-devel] Re: [PATCH] linux-user: Remove ELFLOAD32.
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To: Blue Swirl <blauwirbel@gmail.com>
Cc: qemu-devel@nongnu.org

On 04/23/2010 11:36 AM, Blue Swirl wrote:
> On 4/23/10, Richard Henderson <rth@twiddle.net> wrote:
>> The ABI-specific types used by linux_binprm and image_info
>>  are different after forcing TARGET_ABI32 on.  Which means
>>  that the parameters that load_elf_binary_multi sees are not
>>  those that loader_exec passed.  This is inherently broken
>>  and is more trouble than it's worth fixing.
> 
> Nack. How is this inherently broken?

sizeof(abi_ulong) is different in elfload32.c and linuxload.c,
which means the two files cannot communicate with any type
affected by this change.  Which is both linux_binprm and image_info.

> The problem that elfload32 solves is that the CPU is 64 bit, but the
> ABI and the binaries loaded are still 32 bits. It works nicely for
> sparc32plus binaries (ELFCLASS32, but only for V9 CPUs).

And yet we have a separate sparc32plus-linux-user/qemu-sparc32plus
binary that does that job.

Do we really need qemu-sparc64 to do both jobs?  Because it doesn't.
The only thing that happens is that qemu crashes immediately because
it sees linux_binprm.e_gid at the offset it expects to see
linux_binprm.argc, and fails to copy gid=rth(5000) entries from the
argv array.


r~