[PATCH v2] ide: add missing hwif->portdev freeing on hwif_init() failure

[Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>]

Recent pci_assign_irq() changes uncovered a problem with missing
freeing of ide_port class instance on hwif_init() failure in 
ide_host_register():

ide0: disabled, no IRQ
ide0: failed to initialize IDE interface
ide0: disabling port
cmd64x 0000:00:02.0: IDE controller (0x1095:0x0646 rev 0x07)
CMD64x_IDE 0000:00:02.0: BAR 0: can't reserve [io  0x8050-0x8057]
cmd64x 0000:00:02.0: can't reserve resources
CMD64x_IDE: probe of 0000:00:02.0 failed with error -16
ide_generic: please use "probe_mask=0x3f" module parameter for probing
all legacy ISA IDE ports
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x94/0xd0
sysfs: cannot create duplicate filename '/class/ide_port/ide0'
...

Trace:
[<fffffc00003308a0>] __warn+0x160/0x190
[<fffffc000048c9f4>] sysfs_warn_dup+0x94/0xd0
[<fffffc0000330928>] warn_slowpath_fmt+0x58/0x70
[<fffffc000048c9f4>] sysfs_warn_dup+0x94/0xd0
[<fffffc0000486d40>] kernfs_path_from_node+0x30/0x60
[<fffffc00004874ac>] kernfs_put+0x16c/0x2c0
[<fffffc00004874ac>] kernfs_put+0x16c/0x2c0
[<fffffc000048d010>] sysfs_do_create_link_sd.isra.2+0x100/0x120
[<fffffc00005b9d64>] device_add+0x2a4/0x7c0
[<fffffc00005ba5cc>] device_create_groups_vargs+0x14c/0x170
[<fffffc00005ba518>] device_create_groups_vargs+0x98/0x170
[<fffffc00005ba690>] device_create+0x50/0x70
[<fffffc00005df36c>] ide_host_register+0x48c/0xa00
[<fffffc00005df330>] ide_host_register+0x450/0xa00
[<fffffc00005ba2a0>] device_register+0x20/0x50
[<fffffc00005df330>] ide_host_register+0x450/0xa00
[<fffffc00005df944>] ide_host_add+0x64/0xe0
[<fffffc000079b41c>] kobject_uevent_env+0x16c/0x710
[<fffffc0000310288>] do_one_initcall+0x68/0x260
[<fffffc00007b13bc>] kernel_init+0x1c/0x1a0
[<fffffc00007b13a0>] kernel_init+0x0/0x1a0
[<fffffc0000311868>] ret_from_kernel_thread+0x18/0x20
[<fffffc00007b13a0>] kernel_init+0x0/0x1a0

---[ end trace 24a70433c3e4d374 ]---
ide0: disabling port

Fix the problem by adding missing code to ide_host_register().

Link: http://lkml.kernel.org/r/32ec730f-c1b0-5584-cd35-f8a809122b96@roeck-us.net
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Matt Turner <mattst88@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
---
This should fix sysfs warning and probing of ide_generic driver
driven ports in case of hwif_init() failure (i.e. no IRQ issue
when pci_assign_irq() fix is not present).

v2:
- Fixed typo in the patch description: pci_assing_irq() -> pci_assign_irq().

 drivers/ide/ide-probe.c |    1 +
 1 file changed, 1 insertion(+)

Index: b/drivers/ide/ide-probe.c
===================================================================
--- a/drivers/ide/ide-probe.c	2017-10-02 15:08:16.658662459 +0200
+++ b/drivers/ide/ide-probe.c	2017-10-03 11:59:36.867189557 +0200
@@ -1451,6 +1451,7 @@ int ide_host_register(struct ide_host *h
 		if (hwif_init(hwif) == 0) {
 			printk(KERN_INFO "%s: failed to initialize IDE "
 					 "interface\n", hwif->name);
+			device_unregister(hwif->portdev);
 			device_unregister(&hwif->gendev);
 			ide_disable_port(hwif);
 			continue;