Re: [PATCH net] tg3: Fix soft lockup when tg3_reset_task() fails.

[David Christensen <drc@linux.vnet.ibm.com>]

On 9/3/20 11:28 AM, Michael Chan wrote:
> If tg3_reset_task() fails, the device state is left in an inconsistent
> state with IFF_RUNNING still set but NAPI state not enabled.  A
> subsequent operation, such as ifdown or AER error can cause it to
> soft lock up when it tries to disable NAPI state.
> 
> Fix it by bringing down the device to !IFF_RUNNING state when
> tg3_reset_task() fails.  tg3_reset_task() running from workqueue
> will now call tg3_close() when the reset fails.  We need to
> modify tg3_reset_task_cancel() slightly to avoid tg3_close()
> calling cancel_work_sync() to cancel tg3_reset_task().  Otherwise
> cancel_work_sync() will wait forever for tg3_reset_task() to
> finish.
> 
> Reported-by: David Christensen <drc@linux.vnet.ibm.com>
> Reported-by: Baptiste Covolato <baptiste@arista.com>
> Fixes: db2199737990 ("tg3: Schedule at most one tg3_reset_task run")
> Signed-off-by: Michael Chan <michael.chan@broadcom.com>

Thanks for the patch, I'll have some test time scheduled and let you know.

Dave