Hi Andra, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: f2fb1afc57304f9dd68c20a08270e287470af2eb commit: 0f5c7b7484394e26afc07c063290fb43c4ba42c7 [9016/14891] nitro_enclaves: Add Makefile for the Nitro Enclaves driver config: i386-randconfig-s001-20201014 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.3-rc1-dirty # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout 0f5c7b7484394e26afc07c063290fb43c4ba42c7 # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; "sparse warnings: (new ones prefixed by >>)" vim +1511 drivers/virt/nitro_enclaves/ne_misc_dev.c 9c8eb50fe9e2bb Andra Paraschiv 2020-09-21 1491 38907e124088b2 Andra Paraschiv 2020-09-21 1492 /** 38907e124088b2 Andra Paraschiv 2020-09-21 1493 * ne_enclave_poll() - Poll functionality used for enclave out-of-band events. 38907e124088b2 Andra Paraschiv 2020-09-21 1494 * @file: File associated with this poll function. 38907e124088b2 Andra Paraschiv 2020-09-21 1495 * @wait: Poll table data structure. 38907e124088b2 Andra Paraschiv 2020-09-21 1496 * 38907e124088b2 Andra Paraschiv 2020-09-21 1497 * Context: Process context. 38907e124088b2 Andra Paraschiv 2020-09-21 1498 * Return: 38907e124088b2 Andra Paraschiv 2020-09-21 1499 * * Poll mask. 38907e124088b2 Andra Paraschiv 2020-09-21 1500 */ 38907e124088b2 Andra Paraschiv 2020-09-21 1501 static __poll_t ne_enclave_poll(struct file *file, poll_table *wait) 38907e124088b2 Andra Paraschiv 2020-09-21 1502 { 38907e124088b2 Andra Paraschiv 2020-09-21 1503 __poll_t mask = 0; 38907e124088b2 Andra Paraschiv 2020-09-21 1504 struct ne_enclave *ne_enclave = file->private_data; 38907e124088b2 Andra Paraschiv 2020-09-21 1505 38907e124088b2 Andra Paraschiv 2020-09-21 1506 poll_wait(file, &ne_enclave->eventq, wait); 38907e124088b2 Andra Paraschiv 2020-09-21 1507 38907e124088b2 Andra Paraschiv 2020-09-21 1508 if (!ne_enclave->has_event) 38907e124088b2 Andra Paraschiv 2020-09-21 1509 return mask; 38907e124088b2 Andra Paraschiv 2020-09-21 1510 38907e124088b2 Andra Paraschiv 2020-09-21 @1511 mask = POLLHUP; 38907e124088b2 Andra Paraschiv 2020-09-21 1512 38907e124088b2 Andra Paraschiv 2020-09-21 1513 return mask; 38907e124088b2 Andra Paraschiv 2020-09-21 1514 } 38907e124088b2 Andra Paraschiv 2020-09-21 1515 :::::: The code at line 1511 was first introduced by commit :::::: 38907e124088b2f5b176acdf3d89926c09d3206a nitro_enclaves: Add logic for creating an enclave VM :::::: TO: Andra Paraschiv <andraprs(a)amazon.com&gt; :::::: CC: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org