Hi,
On 26/06/2023 12:56, Michal Orzel wrote:
On 25/06/2023 22:49, Julien Grall wrote:
From: Julien Grall <[email protected]>
UBSAN has been enabled a few years ago on x86 but was never
enabled on Arm because the final binary is bigger than 2MB (
the maximum we can currently handled).
With the recent rework, it is now possible to grow Xen over 2MB.
So there is no more roadblock to enable Xen other than increasing
the reserved area.
On my setup, for arm32, the final binaray was very close to 4MB.
Furthermore, one may want to enable USBAN and GCOV which would put
the binary well-over 4MB (both features require for some space).
Therefore, increase the size to 8MB which should us some margin.
Signed-off-by: Julien Grall <[email protected]>
----
The drawback with this approach is that we are adding 6 new
page-table (3 for boot and 3 for runtime) that are statically
allocated. So the final Xen binary will be 24KB bigger when
neither UBSAN nor GCOV.
If this is not considered acceptable, then we could make the
size of configurable in the Kconfig and decide it based on the
features enabled.
Both of these features are enabled only in a debug build of Xen, so
another option would be to increase Xen size only for a debug build.
At least UBSAN can be selected without DEBUG. For that you need to add
EXPERT.
Anyway, from your comment, it is not clear to me whether you dislike the
existing approach (and why) or you are OK with the increase.
Cheers,
--
Julien Grall
