Re: [PATCH] arm64: Expose TASK_SIZE to userspace via auxv

[Christopher Covington]

On August 17, 2016 6:30:06 AM EDT, Catalin Marinas <catalin.marinas@xxxxxxx> wrote:
>On Tue, Aug 16, 2016 at 02:32:29PM -0400, Christopher Covington wrote:
>> Some userspace applications need to know the maximum virtual address
>they can
>> use (TASK_SIZE).
>
>Just curious, what are the cases needing TASK_SIZE in user space?

Checkpoint/Restore In Userspace and the Mozilla Javascript Engine https://bugzilla.mozilla.org/show_bug.cgi?id=1143022 are the specific cases I've run into. I've heard LuaJIT might have a similar situation. In general I think making allocations from the top down is a shortcut for finding a large unused region of memory.

Thanks,
Cov

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