Re: [PATCH v6 7/9] x86: Enable Syscall User Dispatch

From: Kees Cook
Date: Tue Sep 22 2020 - 15:37:06 EST


On Fri, Sep 04, 2020 at 04:31:45PM -0400, Gabriel Krisman Bertazi wrote:
> Syscall User Dispatch requirements are fully supported in x86. This
> patch flips the switch, marking it as supported. This was tested
> against Syscall User Dispatch selftest.
>
> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
> ---
> arch/x86/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 7101ac64bb20..56ac8de99021 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -150,6 +150,7 @@ config X86
> select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
> select HAVE_ARCH_PREL32_RELOCATIONS
> select HAVE_ARCH_SECCOMP_FILTER
> + select HAVE_ARCH_SYSCALL_USER_DISPATCH

Is this needed at all? I think simply "the architecture uses the generic
entry code" is sufficient to enable it. (Especially since there's a top
level config for SYSCALL_USER_DISPATCH, it feels like overkill).

--
Kees Cook