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s390/pci: Fix leak of struct zpci_dev when zpci_add_device() fails
jira LE-2349 Rebuild_History Non-Buildable kernel-4.18.0-553.40.1.el8_10 commit-author Niklas Schnelle <schnelle@linux.ibm.com> commit 4879610 Empty-Commit: Cherry-Pick Conflicts during history rebuild. Will be included in final tarball splat. Ref for failed cherry-pick at: ciq/ciq_backports/kernel-4.18.0-553.40.1.el8_10/48796104.failed Prior to commit 0467cdd ("s390/pci: Sort PCI functions prior to creating virtual busses") the IOMMU was initialized and the device was registered as part of zpci_create_device() with the struct zpci_dev freed if either resulted in an error. With that commit this was moved into a separate function called zpci_add_device(). While this new function logs when adding failed, it expects the caller not to use and to free the struct zpci_dev on error. This difference between it and zpci_create_device() was missed while changing the callers and the incompletely initialized struct zpci_dev may get used in zpci_scan_configured_device in the error path. This then leads to a crash due to the device not being registered with the zbus. It was also not freed in this case. Fix this by handling the error return of zpci_add_device(). Since in this case the zdev was not added to the zpci_list it can simply be discarded and freed. Also make this more explicit by moving the kref_init() into zpci_add_device() and document that zpci_zdev_get()/zpci_zdev_put() must be used after adding. Cc: stable@vger.kernel.org Fixes: 0467cdd ("s390/pci: Sort PCI functions prior to creating virtual busses") Reviewed-by: Gerd Bayer <gbayer@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> (cherry picked from commit 4879610) Signed-off-by: Jonathan Maple <jmaple@ciq.com> # Conflicts: # arch/s390/pci/pci.c # arch/s390/pci/pci_event.c
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‎ciq/ciq_backports/kernel-4.18.0-553.40.1.el8_10/48796104.failed‎

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s390/pci: Fix leak of struct zpci_dev when zpci_add_device() fails
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jira LE-2349
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Rebuild_History Non-Buildable kernel-4.18.0-553.40.1.el8_10
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commit-author Niklas Schnelle <schnelle@linux.ibm.com>
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commit 48796104c864cf4dafa80bd8c2ce88f9c92a65ea
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Empty-Commit: Cherry-Pick Conflicts during history rebuild.
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Will be included in final tarball splat. Ref for failed cherry-pick at:
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ciq/ciq_backports/kernel-4.18.0-553.40.1.el8_10/48796104.failed
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Prior to commit 0467cdde8c43 ("s390/pci: Sort PCI functions prior to
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creating virtual busses") the IOMMU was initialized and the device was
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registered as part of zpci_create_device() with the struct zpci_dev
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freed if either resulted in an error. With that commit this was moved
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into a separate function called zpci_add_device().
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While this new function logs when adding failed, it expects the caller
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not to use and to free the struct zpci_dev on error. This difference
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between it and zpci_create_device() was missed while changing the
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callers and the incompletely initialized struct zpci_dev may get used in
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zpci_scan_configured_device in the error path. This then leads to
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a crash due to the device not being registered with the zbus. It was
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also not freed in this case. Fix this by handling the error return of
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zpci_add_device(). Since in this case the zdev was not added to the
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zpci_list it can simply be discarded and freed. Also make this more
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explicit by moving the kref_init() into zpci_add_device() and document
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that zpci_zdev_get()/zpci_zdev_put() must be used after adding.
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Cc: stable@vger.kernel.org
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Fixes: 0467cdde8c43 ("s390/pci: Sort PCI functions prior to creating virtual busses")
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Reviewed-by: Gerd Bayer <gbayer@linux.ibm.com>
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Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
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Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
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Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
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(cherry picked from commit 48796104c864cf4dafa80bd8c2ce88f9c92a65ea)
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Signed-off-by: Jonathan Maple <jmaple@ciq.com>
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# Conflicts:
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# arch/s390/pci/pci.c
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# arch/s390/pci/pci_event.c
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diff --cc arch/s390/pci/pci.c
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index 162ca752cec9,6a011d040dfe..000000000000
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--- a/arch/s390/pci/pci.c
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+++ b/arch/s390/pci/pci.c
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@@@ -884,10 -801,34 +885,41 @@@ struct zpci_dev *zpci_create_device(u3
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goto error;
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zdev->state = state;
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++<<<<<<< HEAD
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+ kref_init(&zdev->kref);
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+ mutex_init(&zdev->lock);
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+ mutex_init(&zdev->kzdev_lock);
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+
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++=======
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+ mutex_init(&zdev->state_lock);
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+ mutex_init(&zdev->fmb_lock);
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+ mutex_init(&zdev->kzdev_lock);
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+
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+ return zdev;
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+
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+ error:
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+ zpci_dbg(0, "crt fid:%x, rc:%d\n", fid, rc);
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+ kfree(zdev);
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+ return ERR_PTR(rc);
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+ }
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+
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+ /**
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+ * zpci_add_device() - Add a previously created zPCI device to the zPCI subsystem
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+ * @zdev: The zPCI device to be added
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+ *
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+ * A struct zpci_dev is added to the zPCI subsystem and to a virtual PCI bus creating
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+ * a new one as necessary. A hotplug slot is created and events start to be handled.
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+ * If successful from this point on zpci_zdev_get() and zpci_zdev_put() must be used.
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+ * If adding the struct zpci_dev fails the device was not added and should be freed.
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+ *
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+ * Return: 0 on success, or an error code otherwise
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+ */
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+ int zpci_add_device(struct zpci_dev *zdev)
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+ {
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+ int rc;
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+
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+ zpci_dbg(1, "add fid:%x, fh:%x, c:%d\n", zdev->fid, zdev->fh, zdev->state);
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++>>>>>>> 48796104c864 (s390/pci: Fix leak of struct zpci_dev when zpci_add_device() fails)
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rc = zpci_init_iommu(zdev);
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if (rc)
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goto error;
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@@@ -1168,6 -1105,50 +1201,53 @@@ bool zpci_is_enabled(void
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return s390_pci_initialized;
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}
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++<<<<<<< HEAD
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++=======
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+ static int zpci_cmp_rid(void *priv, const struct list_head *a,
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+ const struct list_head *b)
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+ {
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+ struct zpci_dev *za = container_of(a, struct zpci_dev, entry);
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+ struct zpci_dev *zb = container_of(b, struct zpci_dev, entry);
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+
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+ /*
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+ * PCI functions without RID available maintain original order
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+ * between themselves but sort before those with RID.
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+ */
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+ if (za->rid == zb->rid)
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+ return za->rid_available > zb->rid_available;
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+ /*
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+ * PCI functions with RID sort by RID ascending.
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+ */
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+ return za->rid > zb->rid;
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+ }
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+
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+ static void zpci_add_devices(struct list_head *scan_list)
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+ {
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+ struct zpci_dev *zdev, *tmp;
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+
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+ list_sort(NULL, scan_list, &zpci_cmp_rid);
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+ list_for_each_entry_safe(zdev, tmp, scan_list, entry) {
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+ list_del_init(&zdev->entry);
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+ if (zpci_add_device(zdev))
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+ kfree(zdev);
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+ }
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+ }
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+
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+ int zpci_scan_devices(void)
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+ {
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+ LIST_HEAD(scan_list);
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+ int rc;
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+
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+ rc = clp_scan_pci_devices(&scan_list);
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+ if (rc)
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+ return rc;
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+
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+ zpci_add_devices(&scan_list);
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+ zpci_bus_scan_busses();
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+ return 0;
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+ }
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+
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++>>>>>>> 48796104c864 (s390/pci: Fix leak of struct zpci_dev when zpci_add_device() fails)
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static int __init pci_base_init(void)
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{
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int rc;
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diff --cc arch/s390/pci/pci_event.c
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index b3961f1016ea,7f7b732b3f3e..000000000000
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--- a/arch/s390/pci/pci_event.c
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+++ b/arch/s390/pci/pci_event.c
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@@@ -328,6 -340,10 +328,13 @@@ static void __zpci_event_availability(s
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zdev = zpci_create_device(ccdf->fid, ccdf->fh, ZPCI_FN_STATE_CONFIGURED);
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if (IS_ERR(zdev))
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break;
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++<<<<<<< HEAD
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++=======
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+ if (zpci_add_device(zdev)) {
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+ kfree(zdev);
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+ break;
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+ }
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++>>>>>>> 48796104c864 (s390/pci: Fix leak of struct zpci_dev when zpci_add_device() fails)
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} else {
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/* the configuration request may be stale */
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if (zdev->state != ZPCI_FN_STATE_STANDBY)
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@@@ -337,10 -353,17 +344,22 @@@
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zpci_scan_configured_device(zdev, ccdf->fh);
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break;
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case 0x0302: /* Reserved -> Standby */
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++<<<<<<< HEAD
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+ if (!zdev)
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+ zpci_create_device(ccdf->fid, ccdf->fh, ZPCI_FN_STATE_STANDBY);
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+ else
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++=======
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+ if (!zdev) {
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+ zdev = zpci_create_device(ccdf->fid, ccdf->fh, ZPCI_FN_STATE_STANDBY);
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+ if (IS_ERR(zdev))
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+ break;
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+ if (zpci_add_device(zdev)) {
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+ kfree(zdev);
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+ break;
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+ }
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+ } else {
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++>>>>>>> 48796104c864 (s390/pci: Fix leak of struct zpci_dev when zpci_add_device() fails)
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zpci_update_fh(zdev, ccdf->fh);
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- }
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break;
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case 0x0303: /* Deconfiguration requested */
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if (zdev) {
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* Unmerged path arch/s390/pci/pci.c
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* Unmerged path arch/s390/pci/pci_event.c

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