Re: [PATCH v3 07/32] KVM: arm64: Introduce a BSS section for use at Hyp

[Will Deacon]

On Tue, Mar 02, 2021 at 02:59:37PM +0000, Quentin Perret wrote:
> Currently, the hyp code cannot make full use of a bss, as the kernel
> section is mapped read-only.
> 
> While this mapping could simply be changed to read-write, it would
> intermingle even more the hyp and kernel state than they currently are.
> Instead, introduce a __hyp_bss section, that uses reserved pages, and
> create the appropriate RW hyp mappings during KVM init.
> 
> Signed-off-by: Quentin Perret <qperret@xxxxxxxxxx>
> ---
>  arch/arm64/include/asm/sections.h |  1 +
>  arch/arm64/kernel/vmlinux.lds.S   | 52 ++++++++++++++++++++-----------
>  arch/arm64/kvm/arm.c              | 14 ++++++++-
>  arch/arm64/kvm/hyp/nvhe/hyp.lds.S |  1 +
>  4 files changed, 49 insertions(+), 19 deletions(-)

Acked-by: Will Deacon <will@xxxxxxxxxx>

Will