Re: [PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry

[kernel test robot <lkp@intel.com>]

Hi Vaibhav,

kernel test robot noticed the following build errors:

[auto build test ERROR on powerpc/topic/ppc-kvm]
[also build test ERROR on kvm/queue kvm/next mst-vhost/linux-next linus/master v7.2-rc7 next-20260813]
[cannot apply to kvm/linux-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Vaibhav-Jain/KVM-PPC-Book3S-HV-nestedv2-Don-t-drop-pending-doorbell-across-L2-entry/20260815-070415
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git topic/ppc-kvm
patch link:    https://lore.kernel.org/r/20260803034426.44249-1-vaibhav%40linux.ibm.com
patch subject: [PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry
config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20260815/202608150815.zhSReMmH-lkp@intel.com/config)
compiler: powerpc64-linux-gcc (GCC) 16.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260815/202608150815.zhSReMmH-lkp@intel.com/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 <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202608150815.zhSReMmH-lkp@intel.com/

All errors (new ones prefixed by >>):

   arch/powerpc/kvm/book3s_hv.c: In function 'kvmhv_vcpu_entry_nestedv2':
>> arch/powerpc/kvm/book3s_hv.c:4304:25: error: 'cpu' undeclared (first use in this function)
    4304 |                         cpu->arch.doorbell_request = 0;
         |                         ^~~
   arch/powerpc/kvm/book3s_hv.c:4304:25: note: each undeclared identifier is reported only once for each function it appears in


vim +/cpu +4304 arch/powerpc/kvm/book3s_hv.c

  4248	
  4249	static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
  4250					     unsigned long lpcr, u64 *tb)
  4251	{
  4252		struct kvmhv_nestedv2_io *io;
  4253		unsigned long msr, i;
  4254		int trap;
  4255		long rc;
  4256	
  4257		io = &vcpu->arch.nestedv2_io;
  4258	
  4259		msr = mfmsr();
  4260		kvmppc_msr_hard_disable_set_facilities(vcpu, msr);
  4261		if (lazy_irq_pending())
  4262			return 0;
  4263	
  4264		if (vcpu->arch.doorbell_request)
  4265			kvmppc_set_dpdes(vcpu, 1);
  4266	
  4267		rc = kvmhv_nestedv2_flush_vcpu(vcpu, time_limit);
  4268		if (rc < 0)
  4269			return -EINVAL;
  4270	
  4271		kvmppc_gse_put_u64(io->vcpu_run_input, KVMPPC_GSID_LPCR, lpcr);
  4272	
  4273		accumulate_time(vcpu, &vcpu->arch.in_guest);
  4274		rc = plpar_guest_run_vcpu(0, vcpu->kvm->arch.lpid, vcpu->vcpu_id,
  4275					  &trap, &i);
  4276	
  4277		if (rc != H_SUCCESS) {
  4278			pr_err("KVM Guest Run VCPU hcall failed\n");
  4279			if (rc == H_INVALID_ELEMENT_ID)
  4280				pr_err("KVM: Guest Run VCPU invalid element id at %ld\n", i);
  4281			else if (rc == H_INVALID_ELEMENT_SIZE)
  4282				pr_err("KVM: Guest Run VCPU invalid element size at %ld\n", i);
  4283			else if (rc == H_INVALID_ELEMENT_VALUE)
  4284				pr_err("KVM: Guest Run VCPU invalid element value at %ld\n", i);
  4285			return -EINVAL;
  4286		}
  4287		accumulate_time(vcpu, &vcpu->arch.guest_exit);
  4288	
  4289		*tb = mftb();
  4290		kvmppc_gsm_reset(io->vcpu_message);
  4291		kvmppc_gsm_reset(io->vcore_message);
  4292		kvmppc_gsbm_zero(&io->valids);
  4293	
  4294		rc = kvmhv_nestedv2_parse_output(vcpu);
  4295		if (rc < 0)
  4296			return -EINVAL;
  4297	
  4298		/* Check if privileged door bell was requested and handled */
  4299		if (vcpu->arch.vcore->dpdes) {
  4300			kvmhv_nestedv2_cached_reload(vcpu, KVMPPC_GSID_DPDES);
  4301			if (vcpu->arch.vcore->dpdes)
  4302				vcpu->arch.doorbell_request |= vcpu->arch.vcore->dpdes;
  4303			else
> 4304				cpu->arch.doorbell_request = 0;
  4305		} else {
  4306			vcpu->arch.doorbell_request = 0;
  4307		}
  4308	
  4309		timer_rearm_host_dec(*tb);
  4310	
  4311		/* Record context switch and guest_run_time data */
  4312		if (kvmhv_get_l2_counters_status())
  4313			do_trace_nested_cs_time(vcpu);
  4314	
  4315		return trap;
  4316	}
  4317	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki