[patch 05/18] powerpc/syscall: Use syscall_enter_from_user_mode_randomize_stack()
Thomas Gleixner <[email protected]>
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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))) {