Re: [PATCH v13 6/6] arm64: Add IMA log information in kimage used for kexec

From: Thiago Jung Bauermann
Date: Tue Dec 22 2020 - 20:19:12 EST



Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx> writes:

> 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.
>
> Any existing "linux,ima-kexec-buffer" property in the device tree
> needs to be removed and its corresponding memory reservation in
> the currently running kernel needs to be freed. The address and
> size of the current kernel's IMA measurement log need to be added
> to the device tree's IMA kexec buffer node and memory for the buffer
> needs to be reserved for the log to be carried over to the next kernel
> on the kexec call.
>
> Add address and size fields to "struct kimage_arch" for ARM64 platform
> to hold the address and size of the IMA measurement log buffer. Remove
> any existing "linux,ima-kexec-buffer" property in the device tree and
> free the corresponding memory reservation in the currently running
> kernel. Add "linux,ima-kexec-buffer" property to the device tree and
> reserve the memory for storing the IMA log that needs to be passed from
> the current kernel to the next one.
>
> Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC 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>
> ---
> 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..c85d18b1f2fd 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
> help
> This is new version of kexec system call. This system call is
> file based and takes file descriptors as system call argument

As I suggested in the other email, this should be:

select HAVE_IMA_KEXEC if IMA

--
Thiago Jung Bauermann
IBM Linux Technology Center