From: Julien Grall <[email protected]> In commit 9d267c049d92 ("xen/arm64: Rework the memory layout"), we decided to require Xen to be loaded below 2 TiB to simplify the logic to enable the MMU. The limit was decided based on how known platform boot plus some slack.
We had a recent report that this is not sufficient on the AVA platform with a old firmware [1]. But the restriction is not going to change in Xen 4.18. So document the limit clearly in docs/misc/arm/booting.txt. [1] https://lore.kernel.org/[email protected] Signed-off-by: Julien Grall <[email protected]> Reviewed-by: Michal Orzel <[email protected]> --- Changes in v2: - The limit is 2 TiB no 5 - Remove unnecessary sentence in the docs - Add missing link - Add Michal's reviewed-by I couldn't find a nice way to document it in SUPPORT.md. So I decided to only document the restrict in docs/misc/arm/booting.txt for now. I also couldn't find any way from GRUB/UEFI (I didn't look much) to specify the loading address. --- docs/misc/arm/booting.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/docs/misc/arm/booting.txt b/docs/misc/arm/booting.txt index 02f7bb65ec6d..547f58a7d981 100644 --- a/docs/misc/arm/booting.txt +++ b/docs/misc/arm/booting.txt @@ -21,7 +21,9 @@ The exceptions to this on 32-bit ARM are as follows: zImage protocol should still be used and not the stricter "raw (non-zImage)" protocol described in arm/Booting. -There are no exception on 64-bit ARM. +The exceptions to this on 64-bit ARM are as follows: + + Xen binary should be loaded in memory below 2 TiB. Booting Guests -------------- -- 2.40.1
