Because its not needed. The entry_SYSCALL_64 code isn't ran when KAISER is enabled, we use entry_SYSCALL_64_trampoline instead. Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/kernel/cpu/common.c | 2 +- arch/x86/kernel/process_64.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1515,7 +1515,7 @@ EXPORT_PER_CPU_SYMBOL(__preempt_count); * the top of the kernel stack. Use an extra percpu variable to track the * top of the kernel stack directly. */ -DEFINE_PER_CPU_USER_MAPPED(unsigned long, cpu_current_top_of_stack) = +DEFINE_PER_CPU(unsigned long, cpu_current_top_of_stack) = (unsigned long)&init_thread_union + THREAD_SIZE; EXPORT_PER_CPU_SYMBOL(cpu_current_top_of_stack); --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -59,7 +59,7 @@ #include #endif -__visible DEFINE_PER_CPU_USER_MAPPED(unsigned long, rsp_scratch); +__visible DEFINE_PER_CPU(unsigned long, rsp_scratch); /* Prints also some state that isn't saved in the pt_regs */ void __show_regs(struct pt_regs *regs, int all)