[PATCH v2 3/6] arm: Prepare linker scripts for memory permissions

[Richard Henderson]

On 2/20/25 05:54, Ilias Apalodimas wrote:
> Upcoming patches are switching the memory mappings to RW, RO, RX
> after the U-Boot binary and its data are relocated. Add
> annotations in the linker scripts to and mark text, data, rodata
> sections and align them to a page boundary.
> 
> It's worth noting that .efi_runtime memory permissions are left
> untouched for now. There's two problems with EFI currently.
> 
> The first problem is that we bundle data, rodata and text in a single
> .efi_runtime section which also must be close to .text for now.
> As a result we also dont change the permissions for anything contained
> in CPUDIR/start.o. In order to fix that we have to decoule .text_rest,
> .text and .efi_runtime and have the runtime services on their own
> section with proper memory permission annotations (efi_rodata etc).
> 
> The efi runtime regions (.efi_runtime_rel) can be relocated by the OS when
> the latter is calling SetVirtualAddressMap. Which means we have to
> configure those pages as RX for U-Boot but convert them to RWX just before
> ExitBootServices. It also needs extra code in efi_tuntime relocation
> code since R_AARCH64_NONE are emitted as well if we page align the
> section.
> 
> Due to the above ignore EFI for now and fix it later once we have the
> rest in place.
> 
> Acked-by: Jerome Forissier<jerome.forissier at linaro.org>
> Tested-by: Neil Armstrong<neil.armstrong at linaro.org> # on AML-S905X-CC
> Signed-off-by: Ilias Apalodimas<ilias.apalodimas at linaro.org>
> ---
>   arch/arm/cpu/armv8/u-boot.lds  | 59 +++++++++++++++++++++++-----------
>   include/asm-generic/sections.h |  2 ++
>   2 files changed, 42 insertions(+), 19 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson at linaro.org>

r~