Re: [PATCH 3/6] intel_sgx: driver for Intel Secure Guard eXtensions

[Jethro Beekman <kernel@jbeekman.nl>]

On 25-04-16 10:34, Jarkko Sakkinen wrote:
> diff --git a/drivers/staging/intel_sgx/isgx_ioctl.c
b/drivers/staging/intel_sgx/isgx_ioctl.c
> new file mode 100644
> index 0000000..9d8b36b
> --- /dev/null
> +++ b/drivers/staging/intel_sgx/isgx_ioctl.c
>
> +static long isgx_ioctl_enclave_create(struct file *filep, unsigned int cmd,
> + unsigned long arg)
>
> + secs->base = vm_mmap(filep, 0, secs->size,
> + PROT_READ | PROT_WRITE | PROT_EXEC,
> + MAP_SHARED, 0);

Why does the ioctl interface map userspace memory for an open device? There's
already a perfectly good syscall for that: mmap.

> diff --git a/drivers/staging/intel_sgx/isgx_user.h b/drivers/staging/intel_sgx/isgx_user.h
> new file mode 100644
> index 0000000..672d19c
> --- /dev/null
> +++ b/drivers/staging/intel_sgx/isgx_user.h
> 
> +#define SGX_ADD_SKIP_EEXTEND 0x1
> +
> +struct sgx_add_param {
> +	unsigned long		addr;
> +	unsigned long		user_addr;
> +	struct isgx_secinfo	*secinfo;
> +	unsigned int		flags;
> +};

The hardware supports calling EEXTEND on only a part of a page, I think the
driver should also support that.

Jethro