Re: [PATCH v8 2/2] s390x: KVM: resetting the Topology-Change-Report

kernel test robot
2022-04-21T06:44:14Z

Hi Pierre,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on kvm/master]
[also build test WARNING on v5.18-rc3]
[cannot apply to kvms390/next mst-vhost/linux-next next-20220420]
[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]

url: https://github.com/intel-lab-lkp/linux/commits/Pierre-Morel/s390x-KVM-CPU-Topology/20220420-194302
base: https://git.kernel.org/pub/scm/virt/kvm/kvm.git master
config: s390-allyesconfig (https://download.01.org/0day-ci/archive/20220421/202204210249.JUYt00GG-lkp@intel.com/config)
compiler: s390-linux-gcc (GCC) 11.2.0
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
# https://github.com/intel-lab-lkp/linux/commit/0bdeef651636ac2ef4918fb6e3230614e2fb3581
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Pierre-Morel/s390x-KVM-CPU-Topology/20220420-194302
git checkout 0bdeef651636ac2ef4918fb6e3230614e2fb3581
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash arch/s390/kvm/

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

All warnings (new ones prefixed by >>):

arch/s390/kvm/kvm-s390.c: In function 'kvm_s390_sca_clear_mtcr':
>> arch/s390/kvm/kvm-s390.c:1773:13: warning: variable 'val' set but not used [-Wunused-but-set-variable]
1773 | int val;
| ^~~

vim +/val +1773 arch/s390/kvm/kvm-s390.c

1758
1759 /**
1760 * kvm_s390_sca_clear_mtcr
1761 * @kvm: guest KVM description
1762 *
1763 * Is only relevant if the topology facility is present,
1764 * the caller should check KVM facility 11
1765 *
1766 * Updates the Multiprocessor Topology-Change-Report to signal
1767 * the guest with a topology change.
1768 */
1769 static int kvm_s390_sca_clear_mtcr(struct kvm *kvm)
1770 {
1771 struct bsca_block *sca = kvm->arch.sca;
1772 struct kvm_vcpu *vcpu;
> 1773 int val;
1774
1775 vcpu = kvm_s390_get_first_vcpu(kvm);
1776 if (!vcpu)
1777 return -ENODEV;
1778
1779 ipte_lock(vcpu);
1780 val = READ_ONCE(sca->utility);
1781 WRITE_ONCE(sca->utility, sca->utility & ~SCA_UTILITY_MTCR);
1782 ipte_unlock(vcpu);
1783
1784 return 0;
1785 }
1786

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0-DAY CI Kernel Test Service