On Fri, 2023-03-10 at 17:11 +0100, Borislav Petkov wrote: [...] Thanks on all the text edits. > On Mon, Feb 27, 2023 at 02:29:49PM -0800, Rick Edgecombe wrote: > > diff --git a/arch/x86/entry/syscalls/syscall_64.tbl > > b/arch/x86/entry/syscalls/syscall_64.tbl > > index c84d12608cd2..f65c671ce3b1 100644 > > --- a/arch/x86/entry/syscalls/syscall_64.tbl > > +++ b/arch/x86/entry/syscalls/syscall_64.tbl > > @@ -372,6 +372,7 @@ > > 448 common process_mrelease sys_process_mreleas > > e > > 449 common futex_waitv sys_futex_waitv > > 450 common set_mempolicy_home_node sys_set_mempolicy_h > > ome_node > > +451 64 map_shadow_stack sys_map_shadow_stack > > Yeah, this'll need a manpage too, I presume. But later. I have one to submit. [...] > > + > > + if (addr && addr <= 0xFFFFFFFF) > > < SZ_4G > > > + return -EINVAL; > > Can we use distinct negative retvals in each case so that it is clear > to > userspace where it fails, *if* it fails? Good idea, I think maybe ERANGE.