On Thu, Aug 29, 2024 at 01:36:50AM -0700, Souradeep Chakrabarti wrote:
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 schakrabarti@linux.microsoft.com Reviewed-by: Haiyang Zhang haiyangz@microsoft.com Reviewed-by: Shradha Gupta shradhagupta@linux.microsoft.com
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 | 30 ++++++++++++------- include/net/mana/mana.h | 4 +++ 2 files changed, 24 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index 39f56973746d..bd303c89cfa6 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 (atomic_read(&apc->tx_qp[i].txq.napi_initialized)) {napi_synchronize(napi);napi_disable(napi);netif_napi_del(napi);atomic_set(&apc->tx_qp[i].txq.napi_initialized, 0);}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;
atomic_set(&txq->napi_initialized, 0);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);
atomic_set(&txq->napi_initialized, 1);mana_gd_ring_cq(cq->gdma_cq, SET_ARM_BIT); } @@ -2023,14 +2027,18 @@ static void mana_destroy_rxq(struct mana_port_context *apc, napi = &rxq->rx_cq.napi;
- if (validate_state)
napi_synchronize(napi);
- if (atomic_read(&rxq->napi_initialized)) {
- napi_disable(napi);
if (validate_state)napi_synchronize(napi);
Is this validate_state flag still needed? The new napi_initialized variable will make sure the napi_synchronize() is called only for rxqs that have napi_enabled.
Regards, Shradha.
- xdp_rxq_info_unreg(&rxq->xdp_rxq);
napi_disable(napi);
- netif_napi_del(napi);
netif_napi_del(napi);atomic_set(&rxq->napi_initialized, 0);- }
- xdp_rxq_info_unreg(&rxq->xdp_rxq);
mana_destroy_wq_obj(apc, GDMA_RQ, rxq->rxobj); @@ -2199,6 +2207,7 @@ static struct mana_rxq *mana_create_rxq(struct mana_port_context *apc, rxq->num_rx_buf = RX_BUFFERS_PER_QUEUE; rxq->rxq_idx = rxq_idx; rxq->rxobj = INVALID_MANA_HANDLE;
- atomic_set(&rxq->napi_initialized, 0);
mana_get_rxbuf_cfg(ndev->mtu, &rxq->datasize, &rxq->alloc_size, &rxq->headroom); @@ -2286,6 +2295,8 @@ static struct mana_rxq *mana_create_rxq(struct mana_port_context *apc, napi_enable(&cq->napi);
- atomic_set(&rxq->napi_initialized, 1);
- mana_gd_ring_cq(cq->gdma_cq, SET_ARM_BIT);
out: if (!err) @@ -2336,7 +2347,6 @@ static void mana_destroy_vport(struct mana_port_context *apc) rxq = apc->rxqs[rxq_idx]; if (!rxq) continue;
- mana_destroy_rxq(apc, rxq, true); apc->rxqs[rxq_idx] = NULL; }
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h index 7caa334f4888..be75abd63dc8 100644 --- a/include/net/mana/mana.h +++ b/include/net/mana/mana.h @@ -98,6 +98,8 @@ struct mana_txq { atomic_t pending_sends;
- atomic_t napi_initialized;
- struct mana_stats_tx stats;
}; @@ -335,6 +337,8 @@ struct mana_rxq { bool xdp_flush; int xdp_rc; /* XDP redirect return code */
- atomic_t napi_initialized;
- struct page_pool *page_pool;
/* MUST BE THE LAST MEMBER: -- 2.34.1