On Tue, 2026-07-07 at 21:05 +0200, Thomas Gleixner wrote:
> add_random_kstack_offset() is invoked before syscall_enter_from_user_mode()
> establishes state. That's wrong because add_random_kstack_offset() calls
> into instrumentable code.
> 
> Move it after syscall_enter_from_user_mode() to ensure that state is
> correctly established.
> 
> Signed-off-by: Thomas Gleixner <[email protected]>
> Cc: Michael Ellerman <[email protected]>
> Cc: Shrikanth Hegde <[email protected]>
> Cc: [email protected]
> ---
>  arch/powerpc/kernel/syscall.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> --- a/arch/powerpc/kernel/syscall.c
> +++ b/arch/powerpc/kernel/syscall.c
> @@ -19,8 +19,8 @@ notrace long system_call_exception(struc
>       long ret;
>       syscall_fn f;
>  
> -     add_random_kstack_offset();
>       r0 = syscall_enter_from_user_mode(regs, r0);
> +     add_random_kstack_offset();
>  
>       if (unlikely(r0 >= NR_syscalls)) {
>               if (unlikely(trap_is_unsupported_scv(regs))) {

Reviewed-by: Radu Rendec <[email protected]>

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