[PATCH 4.14 44/68] net/ncsi: Avoid GFP_KERNEL in response handler

Greg Kroah-Hartman
2021-04-15T15:05:06Z

From: Samuel Mendoza-Jonas <sam@mendozajonas.com>

commit b0949618826cbb64e9ba764bdd52aa14eaf5073d upstream.

ncsi_rsp_handler_gc() allocates the filter arrays using GFP_KERNEL in
softirq context, causing the below backtrace. This allocation is only a
few dozen bytes during probing so allocate with GFP_ATOMIC instead.

[ 42.813372] BUG: sleeping function called from invalid context at mm/slab.h:416
[ 42.820900] in_atomic(): 1, irqs_disabled(): 0, pid: 213, name: kworker/0:1
[ 42.827893] INFO: lockdep is turned off.
[ 42.832023] CPU: 0 PID: 213 Comm: kworker/0:1 Tainted: G W 4.13.16-01441-gad99b38 #65
[ 42.841007] Hardware name: Generic DT based system
[ 42.845966] Workqueue: events ncsi_dev_work
[ 42.850251] [<8010a494>] (unwind_backtrace) from [<80107510>] (show_stack+0x20/0x24)
[ 42.858046] [<80107510>] (show_stack) from [<80612770>] (dump_stack+0x20/0x28)
[ 42.865309] [<80612770>] (dump_stack) from [<80148248>] (___might_sleep+0x230/0x2b0)
[ 42.873241] [<80148248>] (___might_sleep) from [<80148334>] (__might_sleep+0x6c/0xac)
[ 42.881129] [<80148334>] (__might_sleep) from [<80240d6c>] (__kmalloc+0x210/0x2fc)
[ 42.888737] [<80240d6c>] (__kmalloc) from [<8060ad54>] (ncsi_rsp_handler_gc+0xd0/0x170)
[ 42.896770] [<8060ad54>] (ncsi_rsp_handler_gc) from [<8060b454>] (ncsi_rcv_rsp+0x16c/0x1d4)
[ 42.905314] [<8060b454>] (ncsi_rcv_rsp) from [<804d86c8>] (__netif_receive_skb_core+0x3c8/0xb50)
[ 42.914158] [<804d86c8>] (__netif_receive_skb_core) from [<804d96cc>] (__netif_receive_skb+0x20/0x7c)
[ 42.923420] [<804d96cc>] (__netif_receive_skb) from [<804de4b0>] (netif_receive_skb_internal+0x78/0x6a4)
[ 42.932931] [<804de4b0>] (netif_receive_skb_internal) from [<804df980>] (netif_receive_skb+0x78/0x158)
[ 42.942292] [<804df980>] (netif_receive_skb) from [<8042f204>] (ftgmac100_poll+0x43c/0x4e8)
[ 42.950855] [<8042f204>] (ftgmac100_poll) from [<804e094c>] (net_rx_action+0x278/0x4c4)
[ 42.958918] [<804e094c>] (net_rx_action) from [<801016a8>] (__do_softirq+0xe0/0x4c4)
[ 42.966716] [<801016a8>] (__do_softirq) from [<8011cd9c>] (do_softirq.part.4+0x50/0x78)
[ 42.974756] [<8011cd9c>] (do_softirq.part.4) from [<8011cebc>] (__local_bh_enable_ip+0xf8/0x11c)
[ 42.983579] [<8011cebc>] (__local_bh_enable_ip) from [<804dde08>] (__dev_queue_xmit+0x260/0x890)
[ 42.992392] [<804dde08>] (__dev_queue_xmit) from [<804df1f0>] (dev_queue_xmit+0x1c/0x20)
[ 43.000689] [<804df1f0>] (dev_queue_xmit) from [<806099c0>] (ncsi_xmit_cmd+0x1c0/0x244)
[ 43.008763] [<806099c0>] (ncsi_xmit_cmd) from [<8060dc14>] (ncsi_dev_work+0x2e0/0x4c8)
[ 43.016725] [<8060dc14>] (ncsi_dev_work) from [<80133dfc>] (process_one_work+0x214/0x6f8)
[ 43.024940] [<80133dfc>] (process_one_work) from [<80134328>] (worker_thread+0x48/0x558)
[ 43.033070] [<80134328>] (worker_thread) from [<8013ba80>] (kthread+0x130/0x174)
[ 43.040506] [<8013ba80>] (kthread) from [<80102950>] (ret_from_fork+0x14/0x24)

Fixes: 062b3e1b6d4f ("net/ncsi: Refactor MAC, VLAN filters")
Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/ncsi/ncsi-rsp.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/ncsi/ncsi-rsp.c
+++ b/net/ncsi/ncsi-rsp.c
@@ -651,7 +651,7 @@ static int ncsi_rsp_handler_gc(struct nc
NCSI_CAP_VLAN_MASK;

size = (rsp->uc_cnt + rsp->mc_cnt + rsp->mixed_cnt) * ETH_ALEN;
- nc->mac_filter.addrs = kzalloc(size, GFP_KERNEL);
+ nc->mac_filter.addrs = kzalloc(size, GFP_ATOMIC);
if (!nc->mac_filter.addrs)
return -ENOMEM;
nc->mac_filter.n_uc = rsp->uc_cnt;
@@ -660,7 +660,7 @@ static int ncsi_rsp_handler_gc(struct nc

nc->vlan_filter.vids = kcalloc(rsp->vlan_cnt,
sizeof(*nc->vlan_filter.vids),
- GFP_KERNEL);
+ GFP_ATOMIC);
if (!nc->vlan_filter.vids)
return -ENOMEM;
/* Set VLAN filters active so they are cleared in the first