Re: [PATCH 10/24] x86/mm/kaiser: Map the entry stack variables

Peter Zijlstra
2017-11-27T17:22:24Z

On Mon, Nov 27, 2017 at 11:49:09AM +0100, Ingo Molnar wrote:
> diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
> index 157f81816915..631e229ab428 100644
> --- a/arch/x86/kernel/process_64.c
> +++ b/arch/x86/kernel/process_64.c
> @@ -59,7 +59,7 @@
> #include <asm/unistd_32_ia32.h>
> #endif
>
> -__visible DEFINE_PER_CPU(unsigned long, rsp_scratch);
> +__visible DEFINE_PER_CPU_USER_MAPPED(unsigned long, rsp_scratch);
>
> /* Prints also some state that isn't saved in the pt_regs */
> void __show_regs(struct pt_regs *regs, int all)

Do we still need this one? It appears to me we'll never actually execute
that part of entry_SYSCALL_64 anymore, due to
entry_SYSCALL_64_trampoline.