Re: [patch 04/18] loongarch/syscall: Use syscall_enter_from_user_mode_randomize_stack()

On Tue, 2026-07-07 at 21:06 +0200, 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().
>=20
> 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.
>=20
> No functional change.
>=20
> Signed-off-by: Thomas Gleixner <[email protected]>
> Cc: Huacai Chen <[email protected]>
> Cc: [email protected]
> ---
> =C2=A0arch/loongarch/kernel/syscall.c |=C2=A0=C2=A0=C2=A0 5 +----
> =C2=A01 file changed, 1 insertion(+), 4 deletions(-)
>=20
> --- a/arch/loongarch/kernel/syscall.c
> +++ b/arch/loongarch/kernel/syscall.c
> @@ -11,7 +11,6 @@
> =C2=A0#include <linux/linkage.h>
> =C2=A0#include <linux/nospec.h>
> =C2=A0#include <linux/objtool.h>
> -#include <linux/randomize_kstack.h>
> =C2=A0#include <linux/syscalls.h>
> =C2=A0#include <linux/unistd.h>
> =C2=A0
> @@ -70,9 +69,7 @@ void noinstr __no_stack_protector do_sys
> =C2=A0	regs->orig_a0 =3D regs->regs[4];
> =C2=A0	regs->regs[4] =3D -ENOSYS;
> =C2=A0
> -	nr =3D syscall_enter_from_user_mode(regs, nr);
> -
> -	add_random_kstack_offset();
> +	nr =3D syscall_enter_from_user_mode_randomize_stack(regs, nr);
> =C2=A0
> =C2=A0	if (nr < NR_syscalls) {
> =C2=A0		syscall_fn =3D sys_call_table[array_index_nospec(nr, NR_syscalls)=
];

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