[kbuild-all] [joro:sev-es-client-v5.8-rc4 48/75] arch/x86/kernel/sev-es.c:484:1: warning: no previous prototype for function 'safe_stack_exc_vmm_communication'

tree: https://git.kernel.org/pub/scm/linux/kernel/git/joro/linux.git sev-es-client-v5.8-rc4 head: 7ee5e0ddab7fa6efbf0937f175a5688a375d55b8 commit: 5a65bee572d9fb041b77c5b034f75cc513dc5235 [48/75] x86/sev-es: Add Runtime #VC Exception Handler config: x86_64-allyesconfig (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 02946de3802d3bc65bc9f2eb9b8d4969b5a7add8) 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 5a65bee572d9fb041b77c5b034f75cc513dc5235 # 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: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication) ^ arch/x86/include/asm/idtentry.h:362:32: note: expanded from macro 'DEFINE_IDTENTRY_VC_SAFE_STACK' DEFINE_IDTENTRY_RAW_ERRORCODE(safe_stack_##func) ^ <scratch space>:508:1: note: expanded from here safe_stack_exc_vmm_communication ^ arch/x86/kernel/sev-es.c:484:1: note: declare 'static' if the function is not intended to be used outside of this translation unit arch/x86/include/asm/idtentry.h:362:2: note: expanded from macro 'DEFINE_IDTENTRY_VC_SAFE_STACK' DEFINE_IDTENTRY_RAW_ERRORCODE(safe_stack_##func) ^ arch/x86/include/asm/idtentry.h:169:19: note: expanded from macro 'DEFINE_IDTENTRY_RAW_ERRORCODE' __visible noinstr void func(struct pt_regs *regs, unsigned long error_code) ^ DEFINE_IDTENTRY_VC_IST(exc_vmm_communication) ^ arch/x86/include/asm/idtentry.h:372:32: note: expanded from macro 'DEFINE_IDTENTRY_VC_IST' DEFINE_IDTENTRY_RAW_ERRORCODE(ist_##func) ^ <scratch space>:23:1: note: expanded from here ist_exc_vmm_communication ^ arch/x86/kernel/sev-es.c:584:1: note: declare 'static' if the function is not intended to be used outside of this translation unit arch/x86/include/asm/idtentry.h:372:2: note: expanded from macro 'DEFINE_IDTENTRY_VC_IST' DEFINE_IDTENTRY_RAW_ERRORCODE(ist_##func) ^ arch/x86/include/asm/idtentry.h:169:19: note: expanded from macro 'DEFINE_IDTENTRY_RAW_ERRORCODE' __visible noinstr void func(struct pt_regs *regs, unsigned long error_code) ^ 2 warnings generated. vim +/safe_stack_exc_vmm_communication +484 arch/x86/kernel/sev-es.c 483 485 { 486 struct sev_es_runtime_data *data = this_cpu_read(runtime_data); 487 struct ghcb_state state; 488 struct es_em_ctxt ctxt; 489 enum es_result result; 490 struct ghcb *ghcb; 491 492 lockdep_assert_irqs_disabled(); 493 instrumentation_begin(); 494 495 /* 496 * This is invoked through an interrupt gate, so IRQs are disabled. The 497 * code below might walk page-tables for user or kernel addresses, so 498 * keep the IRQs disabled to protect us against concurrent TLB flushes. 499 */ 500 501 ghcb = sev_es_get_ghcb(&state); 502 if (!ghcb) { 503 /* 504 * Mark GHCBs inactive so that panic() is able to print the 505 * message. 506 */ 507 data->ghcb_active = false; 508 data->backup_ghcb_active = false; 509 510 panic("Unable to handle #VC exception! GHCB and Backup GHCB are already in use"); 511 } 512 513 vc_ghcb_invalidate(ghcb); 514 result = vc_init_em_ctxt(&ctxt, regs, error_code); 515 516 if (result == ES_OK) 517 result = vc_handle_exitcode(&ctxt, ghcb, error_code); 518 519 sev_es_put_ghcb(&state); 520 521 /* Done - now check the result */ 522 switch (result) { 523 case ES_OK: 524 vc_finish_insn(&ctxt); 525 break; 526 case ES_UNSUPPORTED: 527 pr_err_ratelimited("Unsupported exit-code 0x%02lx in early #VC exception (IP: 0x%lx)\n", 528 error_code, regs->ip); 529 goto fail; 530 case ES_VMM_ERROR: 531 pr_err_ratelimited("Failure in communication with VMM (exit-code 0x%02lx IP: 0x%lx)\n", 532 error_code, regs->ip); 533 goto fail; 534 case ES_DECODE_FAILED: 535 pr_err_ratelimited("Failed to decode instruction (exit-code 0x%02lx IP: 0x%lx)\n", 536 error_code, regs->ip); 537 goto fail; 538 case ES_EXCEPTION: 539 vc_forward_exception(&ctxt); 540 break; 541 case ES_RETRY: 542 /* Nothing to do */ 543 break; 544 default: 545 pr_emerg("Unknown result in %s():%d\n", __func__, result); 546 /* 547 * Emulating the instruction which caused the #VC exception 548 * failed - can't continue so print debug information 549 */ 550 BUG(); 551 } 552 553 out: 554 instrumentation_end(); 555 556 return; 557 558 fail: 559 if (user_mode(regs)) { 560 /* 561 * Do not kill the machine if user-space triggered the 562 * exception. Send SIGBUS instead and let user-space deal with 563 * it. 564 */ 565 force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)0); 566 } else { 567 pr_emerg("PANIC: Unhandled #VC exception in kernel space (result=%d)\n", 568 result); 569 570 /* Show some debug info */ 571 show_regs(regs); 572 573 /* Ask hypervisor to sev_es_terminate */ 574 sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST); 575 576 /* If that fails and we get here - just panic */ 577 panic("Returned from Terminate-Request to Hypervisor\n"); 578 } 579 580 goto out; 581 } 582 583 /* This handler runs on the #VC fall-back stack. It can cause further #VC exceptions */ 585 { 586 instrumentation_begin(); 587 panic("Can't handle #VC exception from unsupported context\n"); 588 instrumentation_end(); 589 } 590 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org