This is a note to let you know that I've just added the patch titled
bnxt: don't enable NAPI until rings are ready
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bnxt-don-t-enable-napi-until-rings-are-ready.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 0a3018223231a09b7078f993e11992de831c5a77
Author: Jakub Kicinski <kuba@xxxxxxxxxx>
Date: Wed Aug 26 12:40:07 2020 -0700
bnxt: don't enable NAPI until rings are ready
[ Upstream commit 96ecdcc992eb7f468b2cf829b0f5408a1fad4668 ]
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@xxxxxx>
Fixes: c0c050c58d84 ("bnxt_en: New Broadcom ethernet driver.")
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Reviewed-by: Michael Chan <michael.chan@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 089d7b9cc409d..4030020f92be5 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -9132,15 +9132,15 @@ static int __bnxt_open_nic(struct bnxt *bp, bool irq_re_init, bool link_re_init)
}
}
- bnxt_enable_napi(bp);
- bnxt_debug_dev_init(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);
+ bnxt_debug_dev_init(bp);
+
if (link_re_init) {
mutex_lock(&bp->link_lock);
rc = bnxt_update_phy_setting(bp);
@@ -9171,10 +9171,6 @@ static int __bnxt_open_nic(struct bnxt *bp, bool irq_re_init, bool link_re_init)
bnxt_vf_reps_open(bp);
return 0;
-open_err:
- bnxt_debug_dev_exit(bp);
- bnxt_disable_napi(bp);
-
open_err_irq:
bnxt_del_napi(bp);
