This happens if assign_name() return failure when called from
ib_register_device(), that will lead to the following panic in every
time that someone touches the port_data's data members.
All the functions that touch the port_data during teardown are called
from ib_device_release() except free_netdevs() that called from multiple
contexts, that's why the check had to be in both of them.
BUG: unable to handle kernel NULL pointer dereference at 00000000000000c0
PGD 0 P4D 0
Oops: 0002 [#1] SMP PTI
CPU: 19 PID: 1994 Comm: systemd-udevd Not tainted 5.1.0-rc5+ #1
Hardware name: HP ProLiant DL360p Gen8, BIOS P71 12/20/2013
RIP: 0010:_raw_spin_lock_irqsave+0x1e/0x40
Code: 85 ff 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 53 9c 58 66 66 90
66 90 48 89 c3 fa 66 66 90 66 66 90 31 c0 ba 01 00 00 00 <f0> 0f b1 17 0f
94 c2 84 d2 74 05 48 89 d8 5b c3 89 c6 e8 b4 85 8a
RSP: 0018:ffffa8d7079a7c08 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000202 RCX: ffffa8d7079a7bf8
RDX: 0000000000000001 RSI: ffff93607c990000 RDI: 00000000000000c0
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffffc08c4dd8
R10: 0000000000000000 R11: 0000000000000001 R12: 00000000000000c0
R13: ffff93607c990000 R14: ffffffffc05a9740 R15: ffffa8d7079a7e98
FS: 00007f1c6ee438c0(0000) GS:ffff93609f6c0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000c0 CR3: 0000000819fca002 CR4: 00000000000606e0
Call Trace:
free_netdevs+0x4d/0xe0 [ib_core]
ib_dealloc_device+0x51/0xb0 [ib_core]
__mlx5_ib_add+0x5e/0x70 [mlx5_ib]
mlx5_add_device+0x57/0xe0 [mlx5_core]
mlx5_register_interface+0x85/0xc0 [mlx5_core]
? 0xffffffffc0474000
do_one_initcall+0x4e/0x1d4
? _cond_resched+0x15/0x30
? kmem_cache_alloc_trace+0x15f/0x1c0
do_init_module+0x5a/0x218
load_module+0x186b/0x1e40
? m_show+0x1c0/0x1c0
__do_sys_finit_module+0x94/0xe0
do_syscall_64+0x5b/0x180
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 8ceb1357b337 ("RDMA/device: Consolidate ib_device per_port data into one place")
Signed-off-by: Kamal Heib <kamalheib1@xxxxxxxxx>
---
drivers/infiniband/core/device.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index 78dc07c6ac4b..788bd56b6694 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -472,6 +472,9 @@ static void ib_device_release(struct device *device)
{
struct ib_device *dev = container_of(device, struct ib_device, dev);
+ if (!dev->port_data)
+ return;
+
free_netdevs(dev);
WARN_ON(refcount_read(&dev->refcount));
ib_cache_release_one(dev);
@@ -1935,6 +1938,9 @@ static void free_netdevs(struct ib_device *ib_dev)
unsigned long flags;
unsigned int port;
+ if (!ib_dev->port_data)
+ return;
+
rdma_for_each_port (ib_dev, port) {
struct ib_port_data *pdata = &ib_dev->port_data[port];
struct net_device *ndev;
--
2.20.1
