RDMA/mlx5: Initialize QP mutex for the debug kernels

In DCT and RSS RAW QP creation flows, the QP mutex wasn't initialized and
the magic field inside lock was missing. This caused to the following
kernel warning for kernels build with CONFIG_DEBUG_MUTEXES.

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 3 PID: 16261 at kernel/locking/mutex.c:938 __mutex_lock+0x60e/0x940
 Modules linked in: bonding nf_tables ipip tunnel4 geneve ip6_udp_tunnel udp_tunnel ip6_gre ip6_tunnel tunnel6 ip_gre gre ip_tunnel mlx5_ib mlx5_core mlxfw ptp pps_core rdma_ucm ib_uverbs ib_ipoib ib_umad openvswitch nsh xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat xt_addrtype xt_conntrack nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 br_netfilter overlay ib_srp scsi_transport_srp rpcrdma ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm ib_core [last unloaded: mlxfw]
 CPU: 3 PID: 16261 Comm: ib_send_bw Not tainted 5.8.0-rc4_for_upstream_min_debug_2020_07_08_22_04 #1
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
 RIP: 0010:__mutex_lock+0x60e/0x940
 Code: c0 0f 84 6d fa ff ff 44 8b 15 4e 9d ba 00 45 85 d2 0f 85 5d fa ff ff 48 c7 c6 f2 de 2b 82 48 c7 c7 f1 8a 2b 82 e8 d2 4d 72 ff <0f> 0b 4c 8b 4d 88 e9 3f fa ff ff f6 c2 04 0f 84 37 fe ff ff 48 89
 RSP: 0018:ffff88810bb8b870 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: ffff88829f1dd880 RSI: 0000000000000000 RDI: ffffffff81192afa
 RBP: ffff88810bb8b910 R08: 0000000000000000 R09: 0000000000000028
 R10: 0000000000000000 R11: 0000000000003f85 R12: 0000000000000002
 R13: ffff88827d8d3ce0 R14: ffffffffa059f615 R15: ffff8882a4d02610
 FS:  00007f3f6988e740(0000) GS:ffff8882f5b80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000556556158000 CR3: 000000010a63c005 CR4: 0000000000360ea0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  ? cmd_exec+0x947/0xe60 [mlx5_core]
  ? __mutex_lock+0x76/0x940
  ? mlx5_ib_qp_set_counter+0x25/0xa0 [mlx5_ib]
  mlx5_ib_qp_set_counter+0x25/0xa0 [mlx5_ib]
  mlx5_ib_counter_bind_qp+0x9b/0xe0 [mlx5_ib]
  __rdma_counter_bind_qp+0x6b/0xa0 [ib_core]
  rdma_counter_bind_qp_auto+0x363/0x520 [ib_core]
  _ib_modify_qp+0x316/0x580 [ib_core]
  ib_modify_qp_with_udata+0x19/0x30 [ib_core]
  modify_qp+0x4c4/0x600 [ib_uverbs]
  ib_uverbs_ex_modify_qp+0x87/0xe0 [ib_uverbs]
  ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0x129/0x1c0 [ib_uverbs]
  ib_uverbs_cmd_verbs.isra.5+0x5d5/0x11f0 [ib_uverbs]
  ? ib_uverbs_handler_UVERBS_METHOD_QUERY_CONTEXT+0x120/0x120 [ib_uverbs]
  ? lock_acquire+0xb9/0x3a0
  ? ib_uverbs_ioctl+0xd0/0x210 [ib_uverbs]
  ? ib_uverbs_ioctl+0x175/0x210 [ib_uverbs]
  ib_uverbs_ioctl+0x14b/0x210 [ib_uverbs]
  ? ib_uverbs_ioctl+0xd0/0x210 [ib_uverbs]
  ksys_ioctl+0x234/0x7d0
  ? exc_page_fault+0x202/0x640
  ? do_syscall_64+0x1f/0x2e0
  __x64_sys_ioctl+0x16/0x20
  do_syscall_64+0x59/0x2e0
  ? asm_exc_page_fault+0x8/0x30
  ? rcu_read_lock_sched_held+0x52/0x60
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: b4aaa1f ("IB/mlx5: Handle type IB_QPT_DRIVER when creating a QP")
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Maor Gottlieb <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>

Author: Leon Romanovsky

drivers/infiniband/hw/mlx5/qp.c

@@ -1852,8 +1852,6 @@ static int create_xrc_tgt_qp(struct mlx5_ib_dev *dev, struct mlx5_ib_qp *qp,
 	u32 *in;
 	int err;
 
-	mutex_init(&qp->mutex);
-
 	if (attr->sq_sig_type == IB_SIGNAL_ALL_WR)
 		qp->sq_signal_bits = MLX5_WQE_CTRL_CQ_UPDATE;
 
@@ -1937,7 +1935,6 @@ static int create_user_qp(struct mlx5_ib_dev *dev, struct ib_pd *pd,
 	u32 *in;
 	int err;
 
-	mutex_init(&qp->mutex);
 	spin_lock_init(&qp->sq.lock);
 	spin_lock_init(&qp->rq.lock);
 
@@ -2128,7 +2125,6 @@ static int create_kernel_qp(struct mlx5_ib_dev *dev, struct ib_pd *pd,
 	u32 *in;
 	int err;
 
-	mutex_init(&qp->mutex);
 	spin_lock_init(&qp->sq.lock);
 	spin_lock_init(&qp->rq.lock);
 
@@ -2969,6 +2965,7 @@ struct ib_qp *mlx5_ib_create_qp(struct ib_pd *pd, struct ib_qp_init_attr *attr,
 		goto free_ucmd;
 	}
 
+	mutex_init(&qp->mutex);
 	qp->type = type;
 	if (udata) {
 		err = process_vendor_flags(dev, qp, params.ucmd, attr);