scsi: qla2xxx: Fix gnl list corruption

[ Upstream commit c98c5da ]

Current code does list element deletion and addition in and out of lock
protection. This patch moves deletion behind lock.

list_add double add: new=ffff9130b5eb89f8, prev=ffff9130b5eb89f8,
    next=ffff9130c6a715f0.
 ------------[ cut here ]------------
 kernel BUG at lib/list_debug.c:31!
 invalid opcode: 0000 [#1] SMP PTI
 CPU: 1 PID: 182395 Comm: kworker/1:37 Kdump: loaded Tainted: G W  OE
 --------- -  - 4.18.0-193.el8.x86_64 #1
 Hardware name: HP ProLiant DL160 Gen8, BIOS J03 02/10/2014
 Workqueue: qla2xxx_wq qla2x00_iocb_work_fn [qla2xxx]
 RIP: 0010:__list_add_valid+0x41/0x50
 Code: 85 94 00 00 00 48 39 c7 74 0b 48 39 d7 74 06 b8 01 00 00 00 c3 48 89 f2
 4c 89 c1 48 89 fe 48 c7 c7 60 83 ad 97 e8 4d bd ce ff <0f> 0b 0f 1f 00 66 2e
 0f 1f 84 00 00 00 00 00 48 8b 07 48 8b 57 08
 RSP: 0018:ffffaba306f47d68 EFLAGS: 00010046
 RAX: 0000000000000058 RBX: ffff9130b5eb8800 RCX: 0000000000000006
 RDX: 0000000000000000 RSI: 0000000000000096 RDI: ffff9130b7456a00
 RBP: ffff9130c6a70a58 R08: 000000000008d7be R09: 0000000000000001
 R10: 0000000000000000 R11: 0000000000000001 R12: ffff9130c6a715f0
 R13: ffff9130b5eb8824 R14: ffff9130b5eb89f8 R15: ffff9130b5eb89f8
 FS:  0000000000000000(0000) GS:ffff9130b7440000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007efcaaef11a0 CR3: 000000005200a002 CR4: 00000000000606e0
 Call Trace:
  qla24xx_async_gnl+0x113/0x3c0 [qla2xxx]
  ? qla2x00_iocb_work_fn+0x53/0x80 [qla2xxx]
  ? process_one_work+0x1a7/0x3b0
  ? worker_thread+0x30/0x390
  ? create_worker+0x1a0/0x1a0
  ? kthread+0x112/0x130

Link: https://lore.kernel.org/r/[email protected]
Fixes: 726b854 ("qla2xxx: Add framework for async fabric discovery")
Reviewed-by: Himanshu Madhani <[email protected]>
Signed-off-by: Quinn Tran <[email protected]>
Signed-off-by: Nilesh Javali <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Author: Quinn Tran

drivers/scsi/qla2xxx/qla_init.c

@@ -976,8 +976,6 @@ static void qla24xx_async_gnl_sp_done(srb_t *sp, int res)
 	    sp->name, res, sp->u.iocb_cmd.u.mbx.in_mb[1],
 	    sp->u.iocb_cmd.u.mbx.in_mb[2]);
 
-	if (res == QLA_FUNCTION_TIMEOUT)
-		return;
 
 	sp->fcport->flags &= ~(FCF_ASYNC_SENT|FCF_ASYNC_ACTIVE);
 	memset(&ea, 0, sizeof(ea));
@@ -1015,8 +1013,8 @@ static void qla24xx_async_gnl_sp_done(srb_t *sp, int res)
 	spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
 
 	list_for_each_entry_safe(fcport, tf, &h, gnl_entry) {
-		list_del_init(&fcport->gnl_entry);
 		spin_lock_irqsave(&vha->hw->tgt.sess_lock, flags);
+		list_del_init(&fcport->gnl_entry);
 		fcport->flags &= ~(FCF_ASYNC_SENT | FCF_ASYNC_ACTIVE);
 		spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
 		ea.fcport = fcport;