drivers/ptp/ptp_vmclock.c:445:24: sparse: sparse: incorrect type in return expression (different base types)

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

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   ef0c9f75a19532d7675384708fc8621e10850104
commit: 3b1526ddb25452385b52f2588b655f524a57070b ptp: vmclock: support device notifications
date:   5 months ago
config: x86_64-randconfig-123-20260622 (https://download.01.org/0day-ci/archive/20260622/202606222129.M1YS26K2-lkp@intel.com/config)
compiler: clang version 22.1.3 (https://github.com/llvm/llvm-project e9846648fd6183ee6d8cbdb4502213fcf902a211)
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260622/202606222129.M1YS26K2-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
| Fixes: 3b1526ddb254 ("ptp: vmclock: support device notifications")
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202606222129.M1YS26K2-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
>> drivers/ptp/ptp_vmclock.c:445:24: sparse: sparse: incorrect type in return expression (different base types) @@     expected restricted __poll_t @@     got int @@
   drivers/ptp/ptp_vmclock.c:445:24: sparse:     expected restricted __poll_t
   drivers/ptp/ptp_vmclock.c:445:24: sparse:     got int
   drivers/ptp/ptp_vmclock.c:451:31: sparse: sparse: incorrect type in return expression (different base types) @@     expected restricted __poll_t @@     got int @@
   drivers/ptp/ptp_vmclock.c:451:31: sparse:     expected restricted __poll_t
   drivers/ptp/ptp_vmclock.c:451:31: sparse:     got int

vim +445 drivers/ptp/ptp_vmclock.c

   433	
   434	static __poll_t vmclock_miscdev_poll(struct file *fp, poll_table *wait)
   435	{
   436		struct vmclock_file_state *fst = fp->private_data;
   437		struct vmclock_state *st = fst->st;
   438		uint32_t seq;
   439	
   440		/*
   441		 * Hypervisor will not send us any notifications, so fail immediately
   442		 * to avoid having caller sleeping for ever.
   443		 */
   444		if (!(le64_to_cpu(st->clk->flags) & VMCLOCK_FLAG_NOTIFICATION_PRESENT))
 > 445			return POLLHUP;
   446	
   447		poll_wait(fp, &st->disrupt_wait, wait);
   448	
   449		seq = le32_to_cpu(st->clk->seq_count);
   450		if (atomic_read(&fst->seq) != seq)
   451			return POLLIN | POLLRDNORM;
   452	
   453		return 0;
   454	}
   455	

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