[Arm-dev] [PATCH v2] config-centos-sig: aarch64: Enable 48 bit VA

Mon Nov 21 17:44:59 UTC 2016
Jim Perrin <jperrin at centos.org>


On 11/18/2016 04:34 PM, Jeremy Linton wrote:
> On 11/18/2016 04:29 PM, Jeremy Linton wrote:
>> The current RHELSA kernel is using a 42bit VA which
>> is too limiting for possible near future workloads.
>> Update this to 48 bits. This patch has a dependency
>> on mozjs versions in the distro being patched to
>> work with virtual address spaces >47 bits.
> 
> Just a quick comment. An easy way to verify that the kernel in use has
> 48bit VA's is to check the /proc/xxx/maps of a userspace process.
> 
> A 48bit VA kernel will place shared libraries into addresses at the top
> of the userspace address region. For example:
> 


In thinking about this a bit more, I'd like to hold off on merging the
48bit VA patches in for the initial install kernel so that we have time
to discuss the potential implications a bit more. We can always
merge/push it as an update once we're a bit more clear on the impact of
the fixes.



-- 
Jim Perrin
The CentOS Project | http://www.centos.org
twitter: @BitIntegrity | GPG Key: FA09AD77