qeth: forbid recovery during shutdown

A recovery does not make sense during shutdown and may even cause an
error like this:

qeth 0.0.f503: A recovery process has been started for the device
Badness at drivers/s390/cio/qdio_main.c:1156
Modules linked in: autofs4 sunrpc dm_multipath scsi_dh scsi_mod qeth_l3 ipv6 vmu
r qeth qdio ccwgroup ext3 jbd mbcache dasd_eckd_mod dasd_mod dm_mirror dm_region
_hash dm_log dm_mod [last unloaded: scsi_wait_scan]
CPU: 3 Not tainted 2.6.32-202.el6.s390x #1
Process qeth_recover (pid: 1498, task: 000000003efe2040, ksp: 000000003d5e3b80)
Krnl PSW : 0404200180000000 000003c000be6da8 (qdio_int_handler+0x88/0x43c [qdio]
)
           R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3
Krnl GPRS: ffffffffffff3bac 0000000000000005 0000000000000000 fffffffffffffff4
           0000000000000000 000000000000000c 0000000000000000 000000003ca97000
           0000000000000380 fffffffffffffff4 000000003f22d800 000000003f22c478
           000003c000bdf000 000003c000bea270 000000003f447e10 000000003f447db0
Krnl Code: 000003c000be6d9a: c21f00000004       clfi    %r1,4
           000003c000be6da0: a7c40021           brc     12,3c000be6de2
           000003c000be6da4: a7f40001           brc     15,3c000be6da6
          >000003c000be6da8: e320a0080004       lg      %r2,8(%r10)
           000003c000be6dae: a7390003           lghi    %r3,3
           000003c000be6db2: a72b0178           aghi    %r2,376
           000003c000be6db6: a7490001           lghi    %r4,1
           000003c000be6dba: a7590000           lghi    %r5,0
Call Trace:
([<000000000080ee80>] __per_cpu_offset+0x0/0x200)
[<00000000003d90e8>] ccw_device_call_handler+0x70/0xcc
[<00000000003d83a2>] ccw_device_irq+0x82/0x180
[<00000000003cc6a8>] do_IRQ+0x16c/0x1ec
[<0000000000118abe>] io_return+0x0/0x8
[<000003c000d04c74>] qeth_determine_capabilities+0x208/0x5cc [qeth]
([<000003c000d04c4a>] qeth_determine_capabilities+0x1de/0x5cc [qeth])
[<000003c000d0a6e0>] qeth_core_hardsetup_card+0x160/0x1258 [qeth]
[<000003c000f49f56>] __qeth_l3_set_online+0x132/0xb14 [qeth_l3]
[<000003c000f4ac70>] qeth_l3_recover+0x168/0x224 [qeth_l3]
[<000000000016e210>] kthread+0xa4/0xac
[<0000000000109c6e>] kernel_thread_starter+0x6/0xc
[<0000000000109c68>] kernel_thread_starter+0x0/0xc

The patch forbids start of a recovery once qeth shutdown is running.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 9754df9..8eff8f7 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -3598,6 +3598,7 @@
 static void qeth_l3_shutdown(struct ccwgroup_device *gdev)
 {
 	struct qeth_card *card = dev_get_drvdata(&gdev->dev);
+	qeth_set_allowed_threads(card, 0, 1);
 	if ((gdev->state == CCWGROUP_ONLINE) && card->info.hwtrap)
 		qeth_hw_trap(card, QETH_DIAGS_TRAP_DISARM);
 	qeth_qdio_clear_card(card, 0);