linux/drivers/net/can/mscan
Florian Faber 2d77bd61a2 can: mscan: mscan_rx_poll(): fix rx path lockup when returning from polling to irq mode
Under load, the RX side of the mscan driver can get stuck while TX still
works. Restarting the interface locks up the system. This behaviour
could be reproduced reliably on a MPC5121e based system.

The patch fixes the return value of the NAPI polling function (should be
the number of processed packets, not constant 1) and the condition under
which IRQs are enabled again after polling is finished.

With this patch, no more lockups were observed over a test period of ten
days.

Fixes: afa17a500a ("net/can: add driver for mscan family & mpc52xx_mscan")
Signed-off-by: Florian Faber <faber@faberman.de>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2020-01-02 15:34:27 +01:00
..
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
mpc5xxx_can.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 344 2019-06-05 17:37:07 +02:00
mscan.c can: mscan: mscan_rx_poll(): fix rx path lockup when returning from polling to irq mode 2020-01-02 15:34:27 +01:00
mscan.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 344 2019-06-05 17:37:07 +02:00