Re: [PATCH RFC V3 9/9] x86/pks: Add PKS test code

[Dave Hansen]

On 10/9/20 12:42 PM, ira.weiny@xxxxxxxxx wrote:
>  #ifdef CONFIG_X86_32
>  	/*
>  	 * We can fault-in kernel-space virtual memory on-demand. The
> diff --git a/include/linux/pkeys.h b/include/linux/pkeys.h
> index cc3510cde64e..f9552bd9341f 100644
> --- a/include/linux/pkeys.h
> +++ b/include/linux/pkeys.h
> @@ -47,7 +47,6 @@ static inline bool arch_pkeys_enabled(void)
>  static inline void copy_init_pkru_to_fpregs(void)
>  {
>  }
> -
>  #endif /* ! CONFIG_ARCH_HAS_PKEYS */

^ Whitespace damage

>  #ifndef CONFIG_ARCH_HAS_SUPERVISOR_PKEYS
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 0c781f912f9f..f015c09ba5a1 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2400,6 +2400,18 @@ config HYPERV_TESTING
>  	help
>  	  Select this option to enable Hyper-V vmbus testing.
>  
> +config PKS_TESTING
> +	bool "PKey(S)upervisor testing"

Seems like we need a space in there somewhere.

> +	pid = fork();
> +	if (pid == 0) {
> +		fd = open("/sys/kernel/debug/x86/run_pks", O_RDWR);
> +		if (fd < 0) {
> +			printf("cannot open file\n");
> +			return -1;
> +		}
> +

Will this return code make anybody mad?  Should we have a nicer return
code for when this is running on non-PKS hardware?

I'm not going to be too picky about this.  I'll just ask one question:
Has this found real bugs for you?

Reviewed-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>