Hi Roman,
Thank you for the contribution.
Roman Skakun writes:
> This patch added additional sanity and increases an understanding for
> getting proper value from the first argument for SMC call on aarch64
> according to SMCC Convention.
>
> [0] ARM DEN0028B, page 12
>
> Signed-off-by: Roman Skakun <roman_ska...@epam.com>
Acked-by: Volodymyr Babchyk <volodymyr_babc...@epam.com>
> ---
> xen/arch/arm/tee/optee.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/xen/arch/arm/tee/optee.c b/xen/arch/arm/tee/optee.c
> index ee85359742..87060b52b8 100644
> --- a/xen/arch/arm/tee/optee.c
> +++ b/xen/arch/arm/tee/optee.c
> @@ -1643,7 +1643,8 @@ static bool optee_handle_call(struct cpu_user_regs
> *regs)
> if ( !ctx )
> return false;
>
> - switch ( get_user_reg(regs, 0) )
> + /* Only least 32 bits are significant (see ARM DEN 0028B, page 12) */
> + switch ( (uint32_t)get_user_reg(regs, 0) )
> {
> case OPTEE_SMC_CALLS_COUNT:
> set_user_reg(regs, 0, OPTEE_MEDIATOR_SMC_COUNT);
--
Volodymyr Babchuk at EPAM
