@@ -712,22 +712,31 @@ static int c_can_set_mode(struct net_device *dev, enum can_mode mode)
return 0;
}
-static int c_can_get_berr_counter(const struct net_device *dev,
- struct can_berr_counter *bec)
+static int __c_can_get_berr_counter(const struct net_device *dev,
+ struct can_berr_counter *bec)
{
unsigned int reg_err_counter;
struct c_can_priv *priv = netdev_priv(dev);
- c_can_pm_runtime_get_sync(priv);
-
reg_err_counter = priv->read_reg(priv, C_CAN_ERR_CNT_REG);
bec->rxerr = (reg_err_counter & ERR_CNT_REC_MASK) >>
ERR_CNT_REC_SHIFT;
bec->txerr = reg_err_counter & ERR_CNT_TEC_MASK;
+ return 0;
+}
+
+static int c_can_get_berr_counter(const struct net_device *dev,
+ struct can_berr_counter *bec)
+{
+ struct c_can_priv *priv = netdev_priv(dev);
+ int err;
+
+ c_can_pm_runtime_get_sync(priv);
+ err = __c_can_get_berr_counter(dev, bec);
c_can_pm_runtime_put_sync(priv);
- return 0;
+ return err;
}
/*
@@ -872,7 +881,7 @@ static int c_can_handle_state_change(struct net_device *dev,
if (unlikely(!skb))
return 0;
- c_can_get_berr_counter(dev, &bec);
+ __c_can_get_berr_counter(dev, &bec);
reg_err_counter = priv->read_reg(priv, C_CAN_ERR_CNT_REG);
rx_err_passive = (reg_err_counter & ERR_CNT_RP_MASK) >>
ERR_CNT_RP_SHIFT;
This is a note to let you know that I have just added a patch titled can: c_can: don't call pm_runtime_get_sync() from interrupt context to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.11.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 30144db2ee1ce173b0d035b645edcb4fcd1639bc Mon Sep 17 00:00:00 2001 From: Marc Kleine-Budde <mkl@pengutronix.de> Date: Sun, 24 Nov 2013 23:31:24 +0100 Subject: can: c_can: don't call pm_runtime_get_sync() from interrupt context commit e35d46adc49b469fd92bdb64fea8af93640e6651 upstream. The c_can driver contians a callpath (c_can_poll -> c_can_state_change -> c_can_get_berr_counter) which may call pm_runtime_get_sync() from the IRQ handler, which is not allowed and results in "BUG: scheduling while atomic". This problem is fixed by introducing __c_can_get_berr_counter, which will not call pm_runtime_get_sync(). Reported-by: Andrew Glen <AGlen@bepmarine.com> Tested-by: Andrew Glen <AGlen@bepmarine.com> Signed-off-by: Andrew Glen <AGlen@bepmarine.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/net/can/c_can/c_can.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) -- 1.8.3.2