diff options
| author | Niklas Schnelle <schnelle@linux.ibm.com> | 2021-01-19 10:49:37 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-25 11:04:05 +0300 |
| commit | 075e3034740cb1910aa857e91f4010bfa2d89652 (patch) | |
| tree | ff069de87fd221262600c5c1c9f99150e8945f12 /arch/s390 | |
| parent | bd37d9b9c4fb2bfb8d2a49f4448663720063c01a (diff) | |
| download | linux-075e3034740cb1910aa857e91f4010bfa2d89652.tar.xz | |
s390/pci: remove superfluous zdev->zbus check
commit e1bff843cde62a45a287b7f9b4cd5e824e8e49e2 upstream.
Checking zdev->zbus for NULL in __zpci_event_availability() is
superfluous as it can never be NULL at this point. While harmless this
check causes smatch warnings because we later access zdev->zbus with
only having checked zdev != NULL which is sufficient.
The reason zdev->zbus can never be NULL is since with zdev != NULL given
we know the zdev came from get_zdev_by_fid() and thus the zpci_list.
Now on first glance at zpci_create_device() one may assume that there is
a window where the zdev is in the list without a zdev, however this
window can't overlap with __zpci_event_availability() as
zpci_create_device() either runs on the same kthread as part of
availability events, or during the initial CLP List PCI at which point
the __zpci_event_availability() is not yet called as zPCI is not yet
initialized.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/pci/pci_event.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/s390/pci/pci_event.c b/arch/s390/pci/pci_event.c index 63727ab4c5be..b4162da4e8a2 100644 --- a/arch/s390/pci/pci_event.c +++ b/arch/s390/pci/pci_event.c @@ -80,7 +80,7 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf) enum zpci_state state; int ret; - if (zdev && zdev->zbus && zdev->zbus->bus) + if (zdev && zdev->zbus->bus) pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn); zpci_err("avail CCDF:\n"); |