On 12.06.18 22:17, Mark Kettenis wrote: >> From: Alexander Graf <ag...@suse.de> >> Date: Tue, 12 Jun 2018 20:46:02 +0200 >> >> On 12.06.18 19:27, Mark Kettenis wrote: >>> The current code that switches into HYP mode doesn't bother to set >>> up a stack for HYP mode. This doesn't work for EFI applications >>> as they expect a usable stack. Fix this by saving the stack >>> pointer before switching and use it to set SP_hyp from monitor. >>> This restores the stack pointer when we drop into HYP mode. >>> >>> Signed-off-by: Mark Kettenis <kette...@openbsd.org> >> >> Can we be sure that the stack in MON is usable from HYP? > > I think so. It is the stack that U-Boot sets up for itself in normal > memory. As far as I can tell arm64 re-uses this stack when dropping > down into EL2 as well.
Well, the question is whether it's secure or non-secure memory. Usually the DRAM controller can be configured to have a window of RAM only available to secure and I'd certainly hope that at least the U-Boot parts that are preserved in EL3 live in such a secured area :) Alex _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
