Re: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

From: Will Deacon
Date: Wed Jan 27 2021 - 11:57:35 EST


On Fri, Jan 15, 2021 at 09:30:17AM -0800, Lakshmi Ramasubramanian wrote:
> Address and size of the buffer containing the IMA measurement log need
> to be passed from the current kernel to the next kernel on kexec.
>
> Add address and size fields to "struct kimage_arch" for ARM64 platform
> to hold the address and size of the IMA measurement log buffer.
>
> Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
> is enabled, to indicate that the IMA measurement log information is
> present in the device tree for ARM64.
>
> Co-developed-by: Prakhar Srivastava <prsriva@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Prakhar Srivastava <prsriva@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>
> Reviewed-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx>
> ---
> arch/arm64/Kconfig | 1 +
> arch/arm64/include/asm/kexec.h | 5 +++++
> 2 files changed, 6 insertions(+)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 1d466addb078..ea7f7fe3dccd 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -1094,6 +1094,7 @@ config KEXEC
> config KEXEC_FILE
> bool "kexec file based system call"
> select KEXEC_CORE
> + select HAVE_IMA_KEXEC if IMA
> help
> This is new version of kexec system call. This system call is
> file based and takes file descriptors as system call argument
> diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
> index d24b527e8c00..2bd19ccb6c43 100644
> --- a/arch/arm64/include/asm/kexec.h
> +++ b/arch/arm64/include/asm/kexec.h
> @@ -100,6 +100,11 @@ struct kimage_arch {
> void *elf_headers;
> unsigned long elf_headers_mem;
> unsigned long elf_headers_sz;
> +
> +#ifdef CONFIG_IMA_KEXEC
> + phys_addr_t ima_buffer_addr;
> + size_t ima_buffer_size;
> +#endif

Why do these need to be in the arch structure instead of 'struct kimage'?

Will