[PATCH 1/2] gpio: pcf857x: Avoid calling irq_domain_cleanup twice

From: George Cherian
Date: Fri May 23 2014 - 01:59:12 EST


Currently irq_domain_cleanup is called twice if irq_domain_init fails.
This causes the following crash.

Unable to handle kernel paging request at virtual address 00100104
pgd = c0004000
[00100104] *pgd=00000000
Internal error: Oops: 805 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 6 Comm: kworker/u4:0 Not tainted 3.12.15-01889-gedd10a8-dirty #4
Workqueue: deferwq deferred_probe_work_func
task: ed0ee800 ti: ed116000 task.ti: ed116000
PC is at irq_domain_remove+0x3c/0x8c
LR is at 0x0
pc : [<c0089734>] lr : [<00000000>] psr: a0000013
sp : ed117b50 ip : 00100100 fp : ed117b64
r10: ed5d1a04 r9 : 00000008 r8 : 00000000
r7 : ffffffea r6 : ed5d1a20 r5 : ed5d1a00 r4 : ed5e7540
r3 : 00200200 r2 : 00100100 r1 : c08aa180 r0 : 00200200
Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 10c53c7d Table: 8000406a DAC: 00000017
Process kworker/u4:0 (pid: 6, stack limit = 0xed116248)
Stack: (0xed117b50 to 0xed118000)
7b40: 0000016b ed5d5f10 ed117b74 ed117b68
7b60: c02c8910 c0089704 ed117bb4 ed117b78 c02c8e14 c02c8900 ed5d1a04 ed5d4e80
...
<snip>
...
fe0: 00000000 00000000 00000000 00000000 00000013 00000000 384a13ea 1590210a
Backtrace:
[<c00896f8>] (irq_domain_remove+0x0/0x8c) from [<c02c8910>] (pcf857x_irq_domain_cleanup+0x1c/0x20)
r4:ed5d5f10 r3:0000016b
[<c02c88f4>] (pcf857x_irq_domain_cleanup+0x0/0x20) from [<c02c8e14>] (pcf857x_probe+0x2a8/0x364)
[<c02c8b6c>] (pcf857x_probe+0x0/0x364) from [<c04787ac>] (i2c_device_probe+0x80/0xc0)
[<c047872c>] (i2c_device_probe+0x0/0xc0) from [<c036c33c>] (driver_probe_device+0x104/0x240)
r6:00000000 r5:ed5d1a20 r4:c08c709c r3:c047872c
[<c036c238>] (driver_probe_device+0x0/0x240) from [<c036c558>] (__device_attach+0x48/0x4c)
r7:ed4fc480 r6:c036c510 r5:ed5d1a20 r4:c0866bb8
[<c036c510>] (__device_attach+0x0/0x4c) from [<c036a6d8>] (bus_for_each_drv+0x4c/0x94)
r5:ed5d1a20 r4:00000000
[<c036a68c>] (bus_for_each_drv+0x0/0x94) from [<c036c1f4>] (device_attach+0x78/0x90)
r6:c087fe50 r5:ed5d1a54 r4:ed5d1a20
[<c036c17c>] (device_attach+0x0/0x90) from [<c036b76c>] (bus_probe_device+0x8c/0xb4)
r6:c087fe50 r5:ed5d1a20 r4:ed5d1a20 r3:ed17e1c0
[<c036b6e0>] (bus_probe_device+0x0/0xb4) from [<c0369888>] (device_add+0x34c/0x624)
r6:ed5d1a28 r5:00000000 r4:ed5d1a20 r3:fffffffe
[<c036953c>] (device_add+0x0/0x624) from [<c0369b7c>] (device_register+0x1c/0x20)
...
<snip>
...
[<c0060844>] (process_one_work+0x0/0x37c) from [<c0061040>] (worker_thread+0x13c/0x3c4)
[<c0060f04>] (worker_thread+0x0/0x3c4) from [<c00670ec>] (kthread+0xac/0xb8)
[<c0067040>] (kthread+0x0/0xb8) from [<c00148b8>] (ret_from_fork+0x14/0x3c)
r7:00000000 r6:00000000 r5:c0067040 r4:ed105d20
Code: e59fc04c e591e000 e59f0048 e154000e (e5823004)
---[ end trace 59dd1e90032c4217 ]---

Signed-off-by: George Cherian <george.cherian@xxxxxx>
---
drivers/gpio/gpio-pcf857x.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c
index 8273582..5acffed 100644
--- a/drivers/gpio/gpio-pcf857x.c
+++ b/drivers/gpio/gpio-pcf857x.c
@@ -319,7 +319,7 @@ static int pcf857x_probe(struct i2c_client *client,
status = pcf857x_irq_domain_init(gpio, client);
if (status < 0) {
dev_err(&client->dev, "irq_domain init failed\n");
- goto fail;
+ goto fail_irq_domain;
}
}

@@ -414,12 +414,13 @@ static int pcf857x_probe(struct i2c_client *client,
return 0;

fail:
- dev_dbg(&client->dev, "probe error %d for '%s'\n",
- status, client->name);
-
if (client->irq)
pcf857x_irq_domain_cleanup(gpio);

+fail_irq_domain:
+ dev_dbg(&client->dev, "probe error %d for '%s'\n",
+ status, client->name);
+
return status;
}

--
1.8.3.1

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