net: aquantia: fix out of memory condition on rx side

On embedded environments with hard memory limits it is a normal although
rare case when skb can't be allocated on rx part under high traffic.

In such OOM cases napi_complete_done() was not called.
So the napi object became in an invalid state like it is "scheduled".
Kernel do not re-schedules the poll of that napi object.

Consequently, kernel can not remove that object the system hangs on
`ifconfig down` waiting for a poll.

We are fixing this by gracefully closing napi poll routine with correct
invocation of napi_complete_done.

This was reproduced with artificially failing the allocation of skb to
simulate an "out of memory" error case and check that traffic does
not get stuck.

Fixes: 970a2e9864 ("net: ethernet: aquantia: Vector operations")
Signed-off-by: Igor Russkikh <igor.russkikh@aquantia.com>
Signed-off-by: Dmitry Bogdanov <dmitry.bogdanov@aquantia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Dmitry Bogdanov 2019-08-30 12:08:38 +00:00 committed by David S. Miller
parent 5c47e3ba6f
commit be6cef69ba
1 changed files with 2 additions and 1 deletions

View File

@ -86,6 +86,7 @@ static int aq_vec_poll(struct napi_struct *napi, int budget)
} }
} }
err_exit:
if (!was_tx_cleaned) if (!was_tx_cleaned)
work_done = budget; work_done = budget;
@ -95,7 +96,7 @@ static int aq_vec_poll(struct napi_struct *napi, int budget)
1U << self->aq_ring_param.vec_idx); 1U << self->aq_ring_param.vec_idx);
} }
} }
err_exit:
return work_done; return work_done;
} }