net: arcnet: Fix RESET flag handling

The main arcnet interrupt handler calls arcnet_close() then
arcnet_open(), if the RESET status flag is encountered.

This is invalid:

  1) In general, interrupt handlers should never call ->ndo_stop() and
     ->ndo_open() functions. They are usually full of blocking calls and
     other methods that are expected to be called only from drivers
     init and exit code paths.

  2) arcnet_close() contains a del_timer_sync(). If the irq handler
     interrupts the to-be-deleted timer, del_timer_sync() will just loop
     forever.

  3) arcnet_close() also calls tasklet_kill(), which has a warning if
     called from irq context.

  4) For device reset, the sequence "arcnet_close(); arcnet_open();" is
     not complete.  Some children arcnet drivers have special init/exit
     code sequences, which then embed a call to arcnet_open() and
     arcnet_close() accordingly. Check drivers/net/arcnet/com20020.c.

Run the device RESET sequence from a scheduled workqueue instead.

Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20210128194802.727770-1-a.darwish@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/net/arcnet/com90xx.c b/drivers/net/arcnet/com90xx.c
index 3dc3d533cb19..d8dfb9ea0de8 100644
--- a/drivers/net/arcnet/com90xx.c
+++ b/drivers/net/arcnet/com90xx.c
@@ -554,7 +554,7 @@ err_free_irq:
 err_release_mem:
 	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 err_free_dev:
-	free_netdev(dev);
+	free_arcdev(dev);
 	return -EIO;
 }
 
@@ -672,7 +672,7 @@ static void __exit com90xx_exit(void)
 		release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
 		release_mem_region(dev->mem_start,
 				   dev->mem_end - dev->mem_start + 1);
-		free_netdev(dev);
+		free_arcdev(dev);
 	}
 }