Kees Cook <keescook@xxxxxxxxxxxx> writes: > 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). Maybe it is not necessary. The reason I have this is to prevent architectures migrating to the generic entry code from inadvertently starting to support this feature, without thinking in advance whether arch_syscall_is_vdso_sigreturn is needed. If that is not a good reason, I'm happy to drop it. -- Gabriel Krisman Bertazi
