From 932ad5d965a7ed50fd53f7869ad72e695b6c9906 Mon Sep 17 00:00:00 2001 From: Igor Russkikh Date: Fri, 6 Nov 2020 18:36:29 -0500 Subject: [PATCH 012/139] [netdrv] net: aquantia: fix out of memory condition on rx side Message-id: <1604687916-15087-13-git-send-email-irusskik@redhat.com> Patchwork-id: 338438 Patchwork-instance: patchwork O-Subject: [RHEL8.4 BZ 1857861 012/139] net: aquantia: fix out of memory condition on rx side Bugzilla: 1857861 RH-Acked-by: David Arcari RH-Acked-by: John Linville RH-Acked-by: Tony Camuso Bugzilla: http://bugzilla.redhat.com/1857861 commit be6cef69ba570ebb327eba1ef6438f7af49aaf86 Author: Dmitry Bogdanov Date: Fri Aug 30 12:08:38 2019 +0000 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: 970a2e9864b0 ("net: ethernet: aquantia: Vector operations") Signed-off-by: Igor Russkikh Signed-off-by: Dmitry Bogdanov Signed-off-by: David S. Miller Signed-off-by: Igor Russkikh Cc: David Arcari Cc: Igor Russkikh Signed-off-by: Jan Stancek --- drivers/net/ethernet/aquantia/atlantic/aq_vec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c index 715685aa48c3..28892b8acd0e 100644 --- a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c +++ b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c @@ -86,6 +86,7 @@ static int aq_vec_poll(struct napi_struct *napi, int budget) } } +err_exit: if (!was_tx_cleaned) 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); } } -err_exit: + return work_done; } -- 2.13.6