Hi Thomas, I love your patch! Yet something to improve: [auto build test ERROR on kvm/linux-next] [cannot apply to tip/auto-latest linus/master linux/master v5.7-rc6 next-20200519] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Thomas-Gleixner/x86-KVM-Async-PF... base: https://git.kernel.org/pub/scm/virt/kvm/kvm.git linux-next config: x86_64-allyesconfig (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project e6658079aca6d971b4e9d7137a3a2ecbc9c34aec) reproduce: 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 # 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(a)intel.com&gt; All errors (new ones prefixed by >>, old ones prefixed by <<): static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu, ^ instrumentation_begin(); ^ arch/x86/kvm/svm/svm.c:3346:2: error: implicit declaration of function 'trace_hardirqs_on_prepare' [-Werror,-Wimplicit-function-declaration] trace_hardirqs_on_prepare(); ^ arch/x86/kvm/svm/svm.c:3346:2: note: did you mean 'trace_hardirqs_on'? include/linux/irqflags.h:32:15: note: 'trace_hardirqs_on' declared here extern void trace_hardirqs_on(void); ^ arch/x86/kvm/svm/svm.c:3347:2: error: implicit declaration of function 'lockdep_hardirqs_on_prepare' [-Werror,-Wimplicit-function-declaration] lockdep_hardirqs_on_prepare(CALLER_ADDR0); ^ arch/x86/kvm/svm/svm.c:3347:2: note: did you mean 'trace_hardirqs_on_prepare'? arch/x86/kvm/svm/svm.c:3346:2: note: 'trace_hardirqs_on_prepare' declared here trace_hardirqs_on_prepare(); ^ instrumentation_end(); ^ arch/x86/kvm/svm/svm.c:3348:2: note: did you mean 'instrumentation_begin'? arch/x86/kvm/svm/svm.c:3345:2: note: 'instrumentation_begin' declared here instrumentation_begin(); ^ arch/x86/kvm/svm/svm.c:3380:2: error: implicit declaration of function 'trace_hardirqs_off_prepare' [-Werror,-Wimplicit-function-declaration] trace_hardirqs_off_prepare(); ^ arch/x86/kvm/svm/svm.c:3380:2: note: did you mean 'trace_hardirqs_on_prepare'? arch/x86/kvm/svm/svm.c:3346:2: note: 'trace_hardirqs_on_prepare' declared here trace_hardirqs_on_prepare(); ^ 6 errors generated. vim +/noinstr +3330 arch/x86/kvm/svm/svm.c 3329 3331 struct vcpu_svm *svm) 3332 { 3333 /* 3334 * VMENTER enables interrupts (host state), but the kernel state is 3335 * interrupts disabled when this is invoked. Also tell RCU about 3336 * it. This is the same logic as for exit_to_user_mode(). 3337 * 3338 * This ensures that e.g. latency analysis on the host observes 3339 * guest mode as interrupt enabled. 3340 * 3341 * guest_enter_irqoff() informs context tracking about the 3342 * transition to guest mode and if enabled adjusts RCU state 3343 * accordingly. 3344 */ 3346 trace_hardirqs_on_prepare(); 3347 lockdep_hardirqs_on_prepare(CALLER_ADDR0); 3349 3350 guest_enter_irqoff(); 3351 lockdep_hardirqs_on(CALLER_ADDR0); 3352 3353 __svm_vcpu_run(svm->vmcb_pa, (unsigned long *)&svm->vcpu.arch.regs); 3354 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org