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From: Richard Henderson <richard.henderson@linaro.org>
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Date: Fri, 16 Mar 2018 19:44:55 +0800
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Subject: Re: [Qemu-devel] [PATCH] linux-user: Allocate extra space for brk
 in PIE executable
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>, 1749393@bugs.launchpad.net

On 03/16/2018 07:01 PM, Peter Maydell wrote:
> PS: do you know what the intention of the
>         if (reserved_va) {
>             mmap_next_start = reserved_va;
>         }
> code in linux-user/main.c is? It seems a bit odd to say "ok,
> we have reserved a big region. we will start trying to mmap
> outside it.", especially when that region covers the full
> 4G that the guest can access...

My guess is that it probably should have been

  mmap_next_start = MIN(TASK_UNMAPPED_BASE, reserved_va);

I can't think of any other reason it should be modified at all.


r~