On 7/8/2026 3:06 AM, Thomas Gleixner wrote:
> syscall_enter_from_user_mode_randomize_stack() replaces
> syscall_enter_from_user_mode() and the subsequent invocation of
> add_random_kstack_offset().
>
> The advantage is that it applies the stack randomization right after
> enter_from_user_mode() and thereby avoids the overhead of get/put_cpu_var()
> as that code is invoked with interrupts disabled.
>
> No functional change.
>
> Signed-off-by: Thomas Gleixner <[email protected]>
> Cc: Paul Walmsley <[email protected]>
> Cc: Palmer Dabbelt <[email protected]>
> Cc: [email protected]
> ---
> arch/riscv/kernel/traps.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> --- a/arch/riscv/kernel/traps.c
> +++ b/arch/riscv/kernel/traps.c
> @@ -7,7 +7,6 @@
> #include <linux/kernel.h>
> #include <linux/init.h>
> #include <linux/irqflags.h>
> -#include <linux/randomize_kstack.h>
> #include <linux/sched.h>
> #include <linux/sched/debug.h>
> #include <linux/sched/signal.h>
> @@ -333,9 +332,7 @@ void do_trap_ecall_u(struct pt_regs *reg
>
> riscv_v_vstate_discard(regs);
>
> - syscall = syscall_enter_from_user_mode(regs, syscall);
> -
> - add_random_kstack_offset();
> + syscall = syscall_enter_from_user_mode_randomize_stack(regs,
> syscall);
Reviewed-by: Jinjie Ruan <[email protected]>
>
> if (syscall >= 0 && syscall < NR_syscalls) {
> syscall = array_index_nospec(syscall, NR_syscalls);
>
