tree:   https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git x86/entry
head:   da0d0553b69e8159a4f25f7981d752e20c22f2ab
commit: 096b735813d5fef5b6b0e80e7585fba57c55e05b [93/119] x86/entry: Switch XEN/PV hypercall entry to IDTENTRY
config: x86_64-allyesconfig (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 3393cc4cebf9969db94dc424b7a2b6195589c33b)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        git checkout 096b735813d5fef5b6b0e80e7585fba57c55e05b
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>

All error/warnings (new ones prefixed by >>, old ones prefixed by <<):

arch/x86/entry/common.c:272:24: warning: no previous prototype for function 'prepare_exit_to_usermode' [-Wmissing-prototypes]
__visible noinstr void prepare_exit_to_usermode(struct pt_regs *regs)
^
arch/x86/entry/common.c:272:19: note: declare 'static' if the function is not intended to be used outside of this translation unit
__visible noinstr void prepare_exit_to_usermode(struct pt_regs *regs)
^
static
arch/x86/entry/common.c:334:24: warning: no previous prototype for function 'syscall_return_slowpath' [-Wmissing-prototypes]
__visible noinstr void syscall_return_slowpath(struct pt_regs *regs)
^
arch/x86/entry/common.c:334:19: note: declare 'static' if the function is not intended to be used outside of this translation unit
__visible noinstr void syscall_return_slowpath(struct pt_regs *regs)
^
static
>> arch/x86/entry/common.c:707:2: error: unknown type name 'boot'; did you mean 'bool'?
boot inhcall = __this_cpu_read(xen_in_preemptible_hcall);
^~~~
bool
include/linux/types.h:30:17: note: 'bool' declared here
typedef _Bool                   bool;
^
>> arch/x86/entry/common.c:731:24: warning: no previous prototype for function 'xen_pv_evtchn_do_upcall' [-Wmissing-prototypes]
__visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
^
arch/x86/entry/common.c:731:19: note: declare 'static' if the function is not intended to be used outside of this translation unit
__visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
^
static
3 warnings and 1 error generated.

vim +707 arch/x86/entry/common.c

   700	
   701	/*
   702	 * In case of scheduling the flag must be cleared and restored after
   703	 * returning from schedule as the task might move to a different CPU.
   704	 */
   705	static __always_inline bool get_and_clear_inhcall(void)
   706	{
 > 707		boot inhcall = __this_cpu_read(xen_in_preemptible_hcall);
   708	
   709		__this_cpu_write(xen_in_preemptible_hcall, false);
   710	}
   711	
   712	static __always_inline void restore_inhcall(bool inhcall)
   713	{
   714		__this_cpu_write(xen_in_preemptible_hcall, inhcall);
   715	}
   716	#else
   717	static __always_inline bool get_and_clear_inhcall(void) { return false; }
   718	static __always_inline void restore_inhcall(bool inhcall) { }
   719	#endif
   720	
   721	static void __xen_pv_evtchn_do_upcall(void)
   722	{
   723		irq_enter_rcu();
   724		inc_irq_stat(irq_hv_callback_count);
   725	
   726		xen_hvm_evtchn_do_upcall();
   727	
   728		irq_exit_rcu();
   729	}
   730	
 > 731	__visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org