Re: [PATCH 1/2] powerpc/prom_init: Replace linux,sml-base/sml-size with linux,sml-log

From: Jarkko Sakkinen
Date: Thu Mar 07 2024 - 15:11:36 EST


On Wed Mar 6, 2024 at 5:55 PM EET, Stefan Berger wrote:
> linux,sml-base holds the address of a buffer with the TPM log. This
> buffer may become invalid after a kexec and therefore embed the whole TPM
> log in linux,sml-log. This helps to protect the log since it is properly
> carried across a kexec with both of the kexec syscalls.

So, I see only description of the problem but nothing how it gets
addressed.

>
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> ---
> arch/powerpc/kernel/prom_init.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
> index e67effdba85c..41268c30de4c 100644
> --- a/arch/powerpc/kernel/prom_init.c
> +++ b/arch/powerpc/kernel/prom_init.c
> @@ -1956,12 +1956,8 @@ static void __init prom_instantiate_sml(void)
>
> reserve_mem(base, size);
>
> - prom_setprop(ibmvtpm_node, "/vdevice/vtpm", "linux,sml-base",
> - &base, sizeof(base));
> - prom_setprop(ibmvtpm_node, "/vdevice/vtpm", "linux,sml-size",
> - &size, sizeof(size));
> -
> - prom_debug("sml base = 0x%llx\n", base);
> + prom_setprop(ibmvtpm_node, "/vdevice/vtpm", "linux,sml-log",
> + (void *)base, size);
> prom_debug("sml size = 0x%x\n", size);
>
> prom_debug("prom_instantiate_sml: end...\n");

BR, Jarkko