Re: [patch 05/18] powerpc/syscall: Use syscall_enter_from_user_mode_randomize_stack()
Mukesh Kumar Chaurasiya <[email protected]>
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On Tue, Jul 07, 2026 at 09:06:15PM +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(). > > 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: Michael Ellerman <[email protected]> > Cc: Shrikanth Hegde <[email protected]> > Cc: [email protected] > --- > arch/powerpc/kernel/syscall.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > --- a/arch/powerpc/kernel/syscall.c > +++ b/arch/powerpc/kernel/syscall.c > @@ -2,7 +2,6 @@ > > #include <linux/compat.h> > #include <linux/context_tracking.h> > -#include <linux/randomize_kstack.h> > #include <linux/entry-common.h> > > #include <asm/interrupt.h> > @@ -19,8 +18,7 @@ notrace long system_call_exception(struc > long ret; > syscall_fn f; > > - r0 = syscall_enter_from_user_mode(regs, r0); > - add_random_kstack_offset(); > + r0 = syscall_enter_from_user_mode_randomize_stack(regs, r0); > > if (unlikely(r0 >= NR_syscalls)) { > if (unlikely(trap_is_unsupported_scv(regs))) { > Reviewed-by: Mukesh Kumar Chaurasiya (IBM) <[email protected]>