[PATCH V4 net] net: mana: Fix error handling in mana_create_txq/rxq's NAPI cleanup
From: Souradeep Chakrabarti <hidden>
Date: 2024-09-02 12:49:06
Also in:
linux-hyperv, linux-rdma, lkml, stable
Subsystem:
hyper-v/azure core and drivers, networking drivers, networking [general], the rest · Maintainers:
"K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Currently napi_disable() gets called during rxq and txq cleanup,
even before napi is enabled and hrtimer is initialized. It causes
kernel panic.
? page_fault_oops+0x136/0x2b0
? page_counter_cancel+0x2e/0x80
? do_user_addr_fault+0x2f2/0x640
? refill_obj_stock+0xc4/0x110
? exc_page_fault+0x71/0x160
? asm_exc_page_fault+0x27/0x30
? __mmdrop+0x10/0x180
? __mmdrop+0xec/0x180
? hrtimer_active+0xd/0x50
hrtimer_try_to_cancel+0x2c/0xf0
hrtimer_cancel+0x15/0x30
napi_disable+0x65/0x90
mana_destroy_rxq+0x4c/0x2f0
mana_create_rxq.isra.0+0x56c/0x6d0
? mana_uncfg_vport+0x50/0x50
mana_alloc_queues+0x21b/0x320
? skb_dequeue+0x5f/0x80
Cc: stable@vger.kernel.org
Fixes: e1b5683ff62e ("net: mana: Move NAPI from EQ to CQ")
Signed-off-by: Souradeep Chakrabarti <redacted>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Shradha Gupta <redacted>
---
V4 -> V3:
Made napi_initialized from atomic_t to bool in txq, as per review comment.
Also used validate_state for rxq as a check.
V3 -> V2:
Instead of using napi internal attribute, using an atomic
attribute to verify napi is initialized for a particular txq / rxq.
V2 -> V1:
Addressed the comment on cleaning up napi for the queues,
where queue creation was successful.
---
drivers/net/ethernet/microsoft/mana/mana_en.c | 22 +++++++++++--------
include/net/mana/mana.h | 2 ++
2 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 39f56973746d..3d151700f658 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c@@ -1872,10 +1872,12 @@ static void mana_destroy_txq(struct mana_port_context *apc) for (i = 0; i < apc->num_queues; i++) { napi = &apc->tx_qp[i].tx_cq.napi; - napi_synchronize(napi); - napi_disable(napi); - netif_napi_del(napi); - + if (apc->tx_qp[i].txq.napi_initialized) { + napi_synchronize(napi); + napi_disable(napi); + netif_napi_del(napi); + apc->tx_qp[i].txq.napi_initialized = false; + } mana_destroy_wq_obj(apc, GDMA_SQ, apc->tx_qp[i].tx_object); mana_deinit_cq(apc, &apc->tx_qp[i].tx_cq);
@@ -1931,6 +1933,7 @@ static int mana_create_txq(struct mana_port_context *apc, txq->ndev = net; txq->net_txq = netdev_get_tx_queue(net, i); txq->vp_offset = apc->tx_vp_offset; + txq->napi_initialized = false; skb_queue_head_init(&txq->pending_skbs); memset(&spec, 0, sizeof(spec));
@@ -1997,6 +2000,7 @@ static int mana_create_txq(struct mana_port_context *apc, netif_napi_add_tx(net, &cq->napi, mana_poll); napi_enable(&cq->napi); + txq->napi_initialized = true; mana_gd_ring_cq(cq->gdma_cq, SET_ARM_BIT); }
@@ -2008,7 +2012,7 @@ static int mana_create_txq(struct mana_port_context *apc, } static void mana_destroy_rxq(struct mana_port_context *apc, - struct mana_rxq *rxq, bool validate_state) + struct mana_rxq *rxq, bool napi_initialized) { struct gdma_context *gc = apc->ac->gdma_dev->gdma_context;
@@ -2023,15 +2027,15 @@ static void mana_destroy_rxq(struct mana_port_context *apc, napi = &rxq->rx_cq.napi; - if (validate_state) + if (napi_initialized) { napi_synchronize(napi); - napi_disable(napi); + napi_disable(napi); + netif_napi_del(napi); + } xdp_rxq_info_unreg(&rxq->xdp_rxq); - netif_napi_del(napi); - mana_destroy_wq_obj(apc, GDMA_RQ, rxq->rxobj); mana_deinit_cq(apc, &rxq->rx_cq);
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 7caa334f4888..b8a6c7504ee1 100644
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h@@ -98,6 +98,8 @@ struct mana_txq { atomic_t pending_sends; + bool napi_initialized; + struct mana_stats_tx stats; };
--
2.34.1