mirror of https://github.com/hak5/openwrt.git
69 lines
2.4 KiB
Diff
69 lines
2.4 KiB
Diff
From 9588c91936434166007c3a15ad7f4e2f3729c5e7 Mon Sep 17 00:00:00 2001
|
|
From: Stephen Boyd <sboyd@codeaurora.org>
|
|
Date: Thu, 6 Mar 2014 22:44:40 -0800
|
|
Subject: [PATCH 026/182] pinctrl: msm: Silence recursive lockdep warning
|
|
|
|
If a driver calls enable_irq_wake() on a gpio turned interrupt
|
|
from the msm pinctrl driver we'll get a lockdep warning like so:
|
|
|
|
=============================================
|
|
[ INFO: possible recursive locking detected ]
|
|
3.14.0-rc3 #2 Not tainted
|
|
---------------------------------------------
|
|
modprobe/52 is trying to acquire lock:
|
|
(&irq_desc_lock_class){-.....}, at: [<c026aea0>] __irq_get_desc_lock+0x48/0x88
|
|
|
|
but task is already holding lock:
|
|
(&irq_desc_lock_class){-.....}, at: [<c026aea0>] __irq_get_desc_lock+0x48/0x88
|
|
|
|
other info that might help us debug this:
|
|
Possible unsafe locking scenario:
|
|
|
|
CPU0
|
|
----
|
|
lock(&irq_desc_lock_class);
|
|
lock(&irq_desc_lock_class);
|
|
|
|
*** DEADLOCK ***
|
|
|
|
May be due to missing lock nesting notation
|
|
|
|
4 locks held by modprobe/52:
|
|
#0: (&__lockdep_no_validate__){......}, at: [<c04f2864>] __driver_attach+0x48/0x98
|
|
#1: (&__lockdep_no_validate__){......}, at: [<c04f2874>] __driver_attach+0x58/0x98
|
|
#2: (&irq_desc_lock_class){-.....}, at: [<c026aea0>] __irq_get_desc_lock+0x48/0x88
|
|
#3: (&(&pctrl->lock)->rlock){......}, at: [<c04bb4b8>] msm_gpio_irq_set_wake+0x20/0xa8
|
|
|
|
Silence it by putting the gpios into their own lock class.
|
|
|
|
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
|
|
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
|
|
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
|
|
---
|
|
drivers/pinctrl/pinctrl-msm.c | 7 +++++++
|
|
1 file changed, 7 insertions(+)
|
|
|
|
--- a/drivers/pinctrl/pinctrl-msm.c
|
|
+++ b/drivers/pinctrl/pinctrl-msm.c
|
|
@@ -857,6 +857,12 @@ static void msm_gpio_irq_handler(unsigne
|
|
chained_irq_exit(chip, desc);
|
|
}
|
|
|
|
+/*
|
|
+ * This lock class tells lockdep that GPIO irqs are in a different
|
|
+ * category than their parents, so it won't report false recursion.
|
|
+ */
|
|
+static struct lock_class_key gpio_lock_class;
|
|
+
|
|
static int msm_gpio_init(struct msm_pinctrl *pctrl)
|
|
{
|
|
struct gpio_chip *chip;
|
|
@@ -895,6 +901,7 @@ static int msm_gpio_init(struct msm_pinc
|
|
|
|
for (i = 0; i < chip->ngpio; i++) {
|
|
irq = irq_create_mapping(pctrl->domain, i);
|
|
+ irq_set_lockdep_class(irq, &gpio_lock_class);
|
|
irq_set_chip_and_handler(irq, &msm_gpio_irq_chip, handle_edge_irq);
|
|
irq_set_chip_data(irq, pctrl);
|
|
}
|