[PATCH 3.19.y-ckt 016/102] usb: chipidea: ehci_init_driver is intended to call one time

[Kamal Mostafa <kamal@canonical.com>]

3.19.8-ckt7 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Peter Chen <peter.chen@freescale.com>

commit 2f01a33bd26545c16fea7592697f7f15c416402b upstream.

The ehci_init_driver is used to initialize hcd APIs for each
ehci controller driver, it is designed to be called only one time
and before driver register is called. The current design will
cause ehci_init_driver is called multiple times at probe process,
it will cause hc_driver's initialization affect current running hcd.

We run out NULL pointer dereference problem when one hcd is started
by module_init, and the other is started by otg thread at SMP platform.
The reason for this problem is ehci_init_driver will do memory copy
for current uniform hc_driver, and this memory copy will do memset (as 0)
first, so when the first hcd is running usb_add_hcd, and the second
hcd may clear the uniform hc_driver's space (at ehci_init_driver),
then the first hcd will meet NULL pointer at the same time.

See below two logs:

LOG_1:
ci_hdrc ci_hdrc.0: EHCI Host Controller
ci_hdrc ci_hdrc.0: new USB bus registered, assigned bus number 1
ci_hdrc ci_hdrc.1: doesn't support gadget
Unable to handle kernel NULL pointer dereference at virtual address 00000014
pgd = 80004000
[00000014] *pgd=00000000
Internal error: Oops: 805 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 108 Comm: kworker/u8:2 Not tainted 3.14.38-222193-g24b2734-dirty #25
Workqueue: ci_otg ci_otg_work
task: d839ec00 ti: d8400000 task.ti: d8400000
PC is at ehci_run+0x4c/0x284
LR is at _raw_spin_unlock_irqrestore+0x28/0x54
pc : [<8041f9a0>]    lr : [<8070ea84>]    psr: 60000113
sp : d8401e30  ip : 00000000  fp : d8004400
r10: 00000001  r9 : 00000001  r8 : 00000000
r7 : 00000000  r6 : d8419940  r5 : 80dd24c0  r4 : d8419800
r3 : 8001d060  r2 : 00000000  r1 : 00000001  r0 : 00000000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c53c7d  Table: 1000404a  DAC: 00000015
Process kworker/u8:2 (pid: 108, stack limit = 0xd8400238)
Stack: (0xd8401e30 to 0xd8402000)
1e20:                                     d87523c0 d8401e48 66667562 d8419800
1e40: 00000000 00000000 d8419800 00000000 00000000 00000000 d84198b0 8040fcdc
1e60: 00000000 80dd320c d8477610 d8419c00 d803d010 d8419800 00000000 00000000
1e80: d8004400 00000000 d8400008 80431494 80431374 d803d100 d803d010 d803d1ac
1ea0: 00000000 80432428 804323d4 d803d100 00000001 80435eb8 80e0d0bc d803d100
1ec0: 00000006 80436458 00000000 d803d100 80e92ec8 80436f44 d803d010 d803d100
1ee0: d83fde00 8043292c d8752710 d803d1f4 d803d010 8042ddfc 8042ddb8 d83f3b00
1f00: d803d1f4 80042b60 00000000 00000003 00000001 00000001 80054598 d83f3b00
1f20: d8004400 d83f3b18 d8004414 d8400000 80e3957b 00000089 d8004400 80043814
1f40: d839ec00 00000000 d83fcd80 d83f3b00 800436e4 00000000 00000000 00000000
1f60: 00000000 80048f34 00000000 00000000 00000000 d83f3b00 00000000 00000000
1f80: d8401f80 d8401f80 00000000 00000000 d8401f90 d8401f90 d8401fac d83fcd80
1fa0: 80048e68 00000000 00000000 8000e538 00000000 00000000 00000000 00000000
1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
[<8041f9a0>] (ehci_run) from [<8040fcdc>] (usb_add_hcd+0x248/0x6e8)
[<8040fcdc>] (usb_add_hcd) from [<80431494>] (host_start+0x120/0x2e4)
[<80431494>] (host_start) from [<80432428>] (ci_otg_start_host+0x54/0xbc)
[<80432428>] (ci_otg_start_host) from [<80435eb8>] (otg_set_protocol+0xa4/0xd0)
[<80435eb8>] (otg_set_protocol) from [<80436458>] (otg_set_state+0x574/0xc58)
[<80436458>] (otg_set_state) from [<80436f44>] (otg_statemachine+0x408/0x46c)
[<80436f44>] (otg_statemachine) from [<8043292c>] (ci_otg_fsm_work+0x3c/0x190)
[<8043292c>] (ci_otg_fsm_work) from [<8042ddfc>] (ci_otg_work+0x44/0x1c4)
[<8042ddfc>] (ci_otg_work) from [<80042b60>] (process_one_work+0xf4/0x35c)
[<80042b60>] (process_one_work) from [<80043814>] (worker_thread+0x130/0x3bc)
[<80043814>] (worker_thread) from [<80048f34>] (kthread+0xcc/0xe4)
[<80048f34>] (kthread) from [<8000e538>] (ret_from_fork+0x14/0x3c)
Code: e5953018 e3530000 0a000000 e12fff33 (e5878014)

LOG_2:
ci_hdrc ci_hdrc.0: EHCI Host Controller
ci_hdrc ci_hdrc.0: new USB bus registered, assigned bus number 1
ci_hdrc ci_hdrc.1: doesn't support gadget
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = 80004000
[00000000] *pgd=00000000
In Online 00:00ternal e      Offline rror: Oops: 80000005 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 108 Comm: kworker/u8:2 Not tainted 3.14.38-02007-g24b2734-dirty #127
Workque Online 00:00ue: ci_o      Offline tg ci_otg_work
Online 00:00task: d8      Offline 39ec00 ti: d83ea000 task.ti: d83ea000
PC is at 0x0
LR is at usb_add_hcd+0x248/0x6e8
pc : [<00000000>]    lr : [<8040f644>]    psr: 60000113
sp : d83ebe60  ip : 00000000  fp : d8004400
r10: 00000001  r9 : 00000001  r8 : d85fd4b0
r7 : 00000000  r6 : 00000000  r5 : 00000000  r4 : d85fd400
r3 : 00000000  r2 : d85fd4f4  r1 : 80410178  r0 : d85fd400
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c53c7d  Table: 1000404a  DAC: 00000015
Process kworker/u8:2 (pid: 108, stack limit = 0xd83ea238)
Stack: (0xd83ebe60 to 0xd83ec000)
be60: 00000000 80dd920c d8654e10 d85fd800 d803e010 d85fd400 00000000 00000000
be80: d8004400 00000000 d83ea008 80430e34 80430d14 d803e100 d803e010 d803e1ac
bea0: 00000000 80431dc8 80431d74 d803e100 00000001 80435858 80e130bc d803e100
bec0: 00000006 80435df8 00000000 d803e100 80e98ec8 804368e4 d803e010 d803e100
bee0: d86e8100 804322cc d86cf050 d803e1f4 d803e010 8042d79c 8042d758 d83cf900
bf00: d803e1f4 80042b78 00000000 00000003 00000001 00000001 800545e8 d83cf900
bf20: d8004400 d83cf918 d8004414 d83ea000 80e3f57b 00000089 d8004400 8004382c
bf40: d839ec00 00000000 d8393780 d83cf900 800436fc 00000000 00000000 00000000
bf60: 00000000 80048f50 80e019f4 00000000 0000264c d83cf900 00000000 00000000
bf80: d83ebf80 d83ebf80 00000000 00000000 d83ebf90 d83ebf90 d83ebfac d8393780
bfa0: 80048e84 00000000 00000000 8000e538 00000000 00000000 00000000 00000000
bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 ee66e85d 133ebd03
[<804 Online 00:000f644>]       Offline (usb_add_hcd) from [<80430e34>] (host_start+0x120/0x2e4)
[<80430e34>] (host_start) from [<80431dc8>] (ci_otg_start_host+0x54/0xbc)
[<80431dc8>] (ci_otg_start_host) from [<80435858>] (otg_set_protocol+0xa4/0xd0)
[<80435858>] (otg_set_protocol) from [<80435df8>] (otg_set_state+0x574/0xc58)
[<80435df8>] (otg_set_state) from [<804368e4>] (otg_statemachine+0x408/0x46c)
[<804368e4>] (otg_statemachine) from [<804322cc>] (ci_otg_fsm_work+0x3c/0x190)
[<804322cc>] (ci_otg_fsm_work) from [<8042d79c>] (ci_otg_work+0x44/0x1c4)
[<8042d79c>] (ci_otg_work) from [<80042b78>] (process_one_work+0xf4/0x35c)
[<80042b78>] (process_one_work) from [<8004382c>] (worker_thread+0x130/0x3bc)
[<8004382c>] (worker_thread) from [<80048f50>] (kthread+0xcc/0xe4)
[<80048f50>] (kthread) from [<8000e538>] (ret_from_fork+0x14/0x3c)
Code: bad PC value

Cc: Jun Li <jun.li@freescale.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
[ kamal: backport to 3.19-stable: context ]
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 drivers/usb/chipidea/core.c | 13 ++++++++++++-
 drivers/usb/chipidea/host.c |  7 +++++--
 drivers/usb/chipidea/host.h |  6 ++++++
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index a57dc88..714da17 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -871,7 +871,18 @@ static struct platform_driver ci_hdrc_driver = {
 	},
 };
 
-module_platform_driver(ci_hdrc_driver);
+static int __init ci_hdrc_platform_register(void)
+{
+	ci_hdrc_host_driver_init();
+	return platform_driver_register(&ci_hdrc_driver);
+}
+module_init(ci_hdrc_platform_register);
+
+static void __exit ci_hdrc_platform_unregister(void)
+{
+	platform_driver_unregister(&ci_hdrc_driver);
+}
+module_exit(ci_hdrc_platform_unregister);
 
 MODULE_ALIAS("platform:ci_hdrc");
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
index 48731d0..d0162d3 100644
--- a/drivers/usb/chipidea/host.c
+++ b/drivers/usb/chipidea/host.c
@@ -175,7 +175,10 @@ int ci_hdrc_host_init(struct ci_hdrc *ci)
 	rdrv->name	= "host";
 	ci->roles[CI_ROLE_HOST] = rdrv;
 
-	ehci_init_driver(&ci_ehci_hc_driver, &ehci_ci_overrides);
-
 	return 0;
 }
+
+void ci_hdrc_host_driver_init(void)
+{
+	ehci_init_driver(&ci_ehci_hc_driver, &ehci_ci_overrides);
+}
diff --git a/drivers/usb/chipidea/host.h b/drivers/usb/chipidea/host.h
index 5707bf3..0f12f13 100644
--- a/drivers/usb/chipidea/host.h
+++ b/drivers/usb/chipidea/host.h
@@ -5,6 +5,7 @@
 
 int ci_hdrc_host_init(struct ci_hdrc *ci);
 void ci_hdrc_host_destroy(struct ci_hdrc *ci);
+void ci_hdrc_host_driver_init(void);
 
 #else
 
@@ -18,6 +19,11 @@ static inline void ci_hdrc_host_destroy(struct ci_hdrc *ci)
 
 }
 
+static void ci_hdrc_host_driver_init(void)
+{
+
+}
+
 #endif
 
 #endif /* __DRIVERS_USB_CHIPIDEA_HOST_H */
-- 
1.9.1