[android-common:android14-6.1 0/8] arch/x86/xen/enlighten_pv.c:650:24: warning: no previous prototype for function 'xen_pv_evtchn_do_upcall'

Hi Brian,

FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant.

tree:   https://android.googlesource.com/kernel/common android14-6.1
head:   9fd3e1d56be51348e5fa5a1633a82a3e82987954
commit: 67d749f3e3516c7343ea6c7fdd38fd3dbfa05936 [0/8] x86/xen: Move Xen upcall handler
config: x86_64-randconfig-004-20260822 (https://download.01.org/0day-ci/archive/20260822/[email protected]/config)
compiler: clang version 22.1.3 (https://github.com/llvm/llvm-project e9846648fd6183ee6d8cbdb4502213fcf902a211)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260822/[email protected]/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

Note: functions only called from assembly code should be annotated with the asmlinkage attribute
All warnings (new ones prefixed by >>):

>> arch/x86/xen/enlighten_pv.c:650:24: warning: no previous prototype for function 'xen_pv_evtchn_do_upcall' [-Wmissing-prototypes]
     650 | __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
         |                        ^
   arch/x86/xen/enlighten_pv.c:650:19: note: declare 'static' if the function is not intended to be used outside of this translation unit
     650 | __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
         |                   ^
         |                   static 
   arch/x86/xen/enlighten_pv.c:1301:34: warning: no previous prototype for function 'xen_start_kernel' [-Wmissing-prototypes]
    1301 | asmlinkage __visible void __init xen_start_kernel(struct start_info *si)
         |                                  ^
   arch/x86/xen/enlighten_pv.c:1301:22: note: declare 'static' if the function is not intended to be used outside of this translation unit
    1301 | asmlinkage __visible void __init xen_start_kernel(struct start_info *si)
         |                      ^
         |                      static 
   2 warnings generated.


vim +/xen_pv_evtchn_do_upcall +650 arch/x86/xen/enlighten_pv.c

   649	
 > 650	__visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
   651	{
   652		irqentry_state_t state = irqentry_enter(regs);
   653		bool inhcall;
   654	
   655		instrumentation_begin();
   656		run_sysvec_on_irqstack_cond(__xen_pv_evtchn_do_upcall, regs);
   657	
   658		inhcall = get_and_clear_inhcall();
   659		if (inhcall && !WARN_ON_ONCE(state.exit_rcu)) {
   660			irqentry_exit_cond_resched();
   661			instrumentation_end();
   662			restore_inhcall(inhcall);
   663		} else {
   664			instrumentation_end();
   665			irqentry_exit(regs, state);
   666		}
   667	}
   668	

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