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Re: [PATCH] Add Prefer_MAP_32BIT_EXEC for Silvermont
- From: "Carlos O'Donell" <carlos at redhat dot com>
- To: "H.J. Lu" <hjl dot tools at gmail dot com>, Jeff Law <law at redhat dot com>
- Cc: Zack Weinberg <zackw at panix dot com>, Andi Kleen <andi at firstfloor dot org>, Adhemerval Zanella <adhemerval dot zanella at linaro dot org>, GNU C Library <libc-alpha at sourceware dot org>
- Date: Tue, 15 Dec 2015 13:38:56 -0500
- Subject: Re: [PATCH] Add Prefer_MAP_32BIT_EXEC for Silvermont
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On 12/15/2015 01:27 PM, Carlos O'Donell wrote:
> + cpu_features->feature[index_Prefer_MAP_32BIT_EXEC]
> + |= get_prefer_map_32bit_exec ();
>
> You wouldn't need get_prefer_map_32bit_exec, since this is all part of
> the code, like dl-librecon.h, which parses the extra env var.
To be clear:
* Add new bit flag definitions for cpu_features.
* Add a sysdeps/unix/sysv/linux/x86_64/dl-silvermont.h
* Fill in EXTRA_LD_ENVVARS or add new ones.
* Write to rtld's GLRO cpu_features the bit you need based
on __libc_enable_secure.
That should simplify and concentrate the Silvermont fixes to
just two files, making future maintenance and documentation
easier.
$0.02.
Cheers,
Carlos.