Ahmed S. Darwish 4d2be0cf27 net: arcnet: Fix RESET flag handling ...

[ Upstream commit 01365633bd1c836240f9bbf86bbeee749795480a ]

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>
Stable-dep-of: 1c40cde6b517 ("arcnet: fix potential memory leak in com20020_probe()")
Signed-off-by: Sasha Levin <sashal@kernel.org>

2022-12-02 17:40:02 +01:00

19 KiB

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