diff options
| author | Thomas Mühlbacher <tmuehlbacher@posteo.net> | 2025-11-15 15:34:56 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-12-07 06:08:23 +0900 |
| commit | 259192ecbe93453eaa0e4fafab056c1bb91afbf4 (patch) | |
| tree | e7237abde6a78a6b92cf3b7993f5c216d77e6138 | |
| parent | 1b60f42a639999c37da7f1fbfa1ad29cf4cbdd2d (diff) | |
can: sja1000: fix max irq loop handling
commit 30db4451c7f6aabcada029b15859a76962ec0cf8 upstream.
Reading the interrupt register `SJA1000_IR` causes all of its bits to be
reset. If we ever reach the condition of handling more than
`SJA1000_MAX_IRQ` IRQs, we will have read the register and reset all its
bits but without actually handling the interrupt inside of the loop
body.
This may, among other issues, cause us to never `netif_wake_queue()`
again after a transmission interrupt.
Fixes: 429da1cc841b ("can: Driver for the SJA1000 CAN controller")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Mühlbacher <tmuehlbacher@posteo.net>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251115153437.11419-1-tmuehlbacher@posteo.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/can/sja1000/sja1000.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c index ee34baeb2afe..075fbef07ef2 100644 --- a/drivers/net/can/sja1000/sja1000.c +++ b/drivers/net/can/sja1000/sja1000.c @@ -511,8 +511,8 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id) if (priv->read_reg(priv, SJA1000_IER) == IRQ_OFF) goto out; - while ((isrc = priv->read_reg(priv, SJA1000_IR)) && - (n < SJA1000_MAX_IRQ)) { + while ((n < SJA1000_MAX_IRQ) && + (isrc = priv->read_reg(priv, SJA1000_IR))) { status = priv->read_reg(priv, SJA1000_SR); /* check for absent controller due to hw unplug */ |