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Miller" , Andreas Larsson , linux-snps-arc@lists.infradead.org, linux-hexagon@vger.kernel.org, linux-openrisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, Michal =?ISO-8859-1?Q?Such=E1nek?= , Jonathan Corbet , linux-doc@vger.kernel.org Date: Wed, 08 Jul 2026 14:35:48 -0400 In-Reply-To: <20260707190253.918861529@kernel.org> References: <20260707181957.433213175@kernel.org> <20260707190253.918861529@kernel.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 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 > Cc: Michael Ellerman > Cc: Shrikanth Hegde > Cc: linuxppc-dev@lists.ozlabs.org > --- > =C2=A0arch/powerpc/kernel/syscall.c |=C2=A0=C2=A0=C2=A0 4 +--- > =C2=A01 file changed, 1 insertion(+), 3 deletions(-) >=20 > --- a/arch/powerpc/kernel/syscall.c > +++ b/arch/powerpc/kernel/syscall.c > @@ -2,7 +2,6 @@ > =C2=A0 > =C2=A0#include > =C2=A0#include > -#include > =C2=A0#include > =C2=A0 > =C2=A0#include > @@ -19,8 +18,7 @@ notrace long system_call_exception(struc > =C2=A0 long ret; > =C2=A0 syscall_fn f; > =C2=A0 > - r0 =3D syscall_enter_from_user_mode(regs, r0); > - add_random_kstack_offset(); > + r0 =3D syscall_enter_from_user_mode_randomize_stack(regs, r0); > =C2=A0 > =C2=A0 if (unlikely(r0 >=3D NR_syscalls)) { > =C2=A0 if (unlikely(trap_is_unsupported_scv(regs))) { Reviewed-by: Radu Rendec