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| author | Marc Kleine-Budde <mkl@pengutronix.de> | 2013-11-24 23:31:24 +0100 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2013-11-25 21:48:51 +0100 |
| commit | e35d46adc49b469fd92bdb64fea8af93640e6651 (patch) | |
| tree | 450dc5d0e82ae23c24cdd2374ba578f904b81b2f | |
| parent | can: sja1000: fix {pre,post}_irq() handling and IRQ handler return value (diff) | |
| download | linux-e35d46adc49b469fd92bdb64fea8af93640e6651.tar.xz linux-e35d46adc49b469fd92bdb64fea8af93640e6651.zip | |
can: c_can: don't call pm_runtime_get_sync() from interrupt context
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>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| -rw-r--r-- | drivers/net/can/c_can/c_can.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c index e3fc07cf2f62..e59c42b446a9 100644 --- a/drivers/net/can/c_can/c_can.c +++ b/drivers/net/can/c_can/c_can.c @@ -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; |