From: Jakub Kicinski kuba@kernel.org
commit 96ecdcc992eb7f468b2cf829b0f5408a1fad4668 upstream.
Netpoll can try to poll napi as soon as napi_enable() is called. It crashes trying to access a doorbell which is still NULL:
BUG: kernel NULL pointer dereference, address: 0000000000000000 CPU: 59 PID: 6039 Comm: ethtool Kdump: loaded Tainted: G S 5.9.0-rc1-00469-g5fd99b5d9950-dirty #26 RIP: 0010:bnxt_poll+0x121/0x1c0 Code: c4 20 44 89 e0 5b 5d 41 5c 41 5d 41 5e 41 5f c3 41 8b 86 a0 01 00 00 41 23 85 18 01 00 00 49 8b 96 a8 01 00 00 0d 00 00 00 24 <89> 02 41 f6 45 77 02 74 cb 49 8b ae d8 01 00 00 31 c0 c7 44 24 1a netpoll_poll_dev+0xbd/0x1a0 __netpoll_send_skb+0x1b2/0x210 netpoll_send_udp+0x2c9/0x406 write_ext_msg+0x1d7/0x1f0 console_unlock+0x23c/0x520 vprintk_emit+0xe0/0x1d0 printk+0x58/0x6f x86_vector_activate.cold+0xf/0x46 __irq_domain_activate_irq+0x50/0x80 __irq_domain_activate_irq+0x32/0x80 __irq_domain_activate_irq+0x32/0x80 irq_domain_activate_irq+0x25/0x40 __setup_irq+0x2d2/0x700 request_threaded_irq+0xfb/0x160 __bnxt_open_nic+0x3b1/0x750 bnxt_open_nic+0x19/0x30 ethtool_set_channels+0x1ac/0x220 dev_ethtool+0x11ba/0x2240 dev_ioctl+0x1cf/0x390 sock_do_ioctl+0x95/0x130
Reported-by: Rob Sherwood rsher@fb.com Fixes: c0c050c58d84 ("bnxt_en: New Broadcom ethernet driver.") Signed-off-by: Jakub Kicinski kuba@kernel.org Reviewed-by: Michael Chan michael.chan@broadcom.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -6378,14 +6378,14 @@ static int __bnxt_open_nic(struct bnxt * } }
- bnxt_enable_napi(bp); - rc = bnxt_init_nic(bp, irq_re_init); if (rc) { netdev_err(bp->dev, "bnxt_init_nic err: %x\n", rc); - goto open_err; + goto open_err_irq; }
+ bnxt_enable_napi(bp); + if (link_re_init) { mutex_lock(&bp->link_lock); rc = bnxt_update_phy_setting(bp); @@ -6410,9 +6410,6 @@ static int __bnxt_open_nic(struct bnxt * bnxt_vf_reps_open(bp); return 0;
-open_err: - bnxt_disable_napi(bp); - open_err_irq: bnxt_del_napi(bp);