tree: https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git locking/kcsan head: ffed638b6a2180da8fd002a46632d746af72b299 commit: 7b364f0949ae2dd205d5e9afa4b82ee17030d928 [14/21] READ_ONCE: Drop pointer qualifiers when reading from scalar types reproduce: # apt-get install sparse # sparse version: v0.6.1-193-gb8fad4bc-dirty git checkout 7b364f0949ae2dd205d5e9afa4b82ee17030d928 make ARCH=x86_64 allmodconfig make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; sparse warnings: (new ones prefixed by >>) include/linux/mm.h:1953:21: sparse: sparse: context imbalance in 'gmap_make_secure' - different lock contexts for basic block -- arch/s390/mm/gmap.c:689:17: sparse: sparse: context imbalance in '__gmap_zap' - different lock contexts for basic block arch/s390/mm/gmap.c:859:16: sparse: sparse: context imbalance in 'gmap_pte_op_walk' - different lock contexts for basic block arch/s390/mm/gmap.c:898:28: sparse: sparse: context imbalance in 'gmap_pte_op_end' - unexpected unlock arch/s390/mm/gmap.c:1004:12: sparse: sparse: context imbalance in 'gmap_protect_pte' - different lock contexts for basic block arch/s390/mm/gmap.c:942:28: sparse: sparse: context imbalance in 'gmap_protect_range' - unexpected unlock arch/s390/mm/gmap.c:2459:6: sparse: sparse: context imbalance in 'gmap_sync_dirty_log_pmd' - different lock contexts for basic block -- arch/s390/kvm/gaccess.c:314:23: sparse: sparse: cast to non-scalar arch/s390/kvm/gaccess.c:314:23: sparse: sparse: cast from non-scalar arch/s390/kvm/gaccess.c:332:23: sparse: sparse: cast to non-scalar arch/s390/kvm/gaccess.c:332:23: sparse: sparse: cast from non-scalar arch/s390/kvm/gaccess.c:352:23: sparse: sparse: cast to non-scalar arch/s390/kvm/gaccess.c:352:23: sparse: sparse: cast from non-scalar vim +163 arch/s390/kernel/uv.c 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 159 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 160 static int make_secure_pte(pte_t *ptep, unsigned long addr, 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 161 struct page *exp_page, struct uv_cb_header *uvcb) 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 162 { 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 @163 pte_t entry = READ_ONCE(*ptep); 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 164 struct page *page; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 165 int expected, rc = 0; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 166 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 167 if (!pte_present(entry)) 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 168 return -ENXIO; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 169 if (pte_val(entry) & _PAGE_INVALID) 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 170 return -ENXIO; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 171 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 172 page = pte_page(entry); 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 173 if (page != exp_page) 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 174 return -ENXIO; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 175 if (PageWriteback(page)) 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 176 return -EAGAIN; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 177 expected = expected_page_refs(page); 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 178 if (!page_ref_freeze(page, expected)) 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 179 return -EBUSY; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 180 set_bit(PG_arch_1, &page->flags); 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 181 rc = uv_call(0, (u64)uvcb); 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 182 page_ref_unfreeze(page, expected); 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 183 /* Return -ENXIO if the page was not mapped, -EINVAL otherwise */ 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 184 if (rc) 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 185 rc = uvcb->rc == 0x10a ? -ENXIO : -EINVAL; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 186 return rc; 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 187 } 214d9bbcd3a672 Claudio Imbrenda 2020-01-21 188 :::::: The code at line 163 was first introduced by commit :::::: 214d9bbcd3a67230b932f6cea83c078ab34d9e70 s390/mm: provide memory management functions for protected KVM guests :::::: TO: Claudio Imbrenda <imbrenda(a)linux.ibm.com&gt; :::::: CC: Christian Borntraeger <borntraeger(a)de.ibm.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org