[ Upstream commit 27b141fc234a3670d21bd742c35d7205d03cbb3a ]
clang points out that the return code from this function is
undefined for one of the error paths:
../drivers/s390/net/ctcm_main.c:1595:7: warning: variable 'result' is used uninitialized whenever 'if' condition is true
[-Wsometimes-uninitialized]
if (priv->channel[direction] == NULL) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../drivers/s390/net/ctcm_main.c:1638:9: note: uninitialized use occurs here
return result;
^~~~~~
../drivers/s390/net/ctcm_main.c:1595:3: note: remove the 'if' if its condition is always false
if (priv->channel[direction] == NULL) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../drivers/s390/net/ctcm_main.c:1539:12: note: initialize the variable 'result' to silence this warning
int result;
^
Make it return -ENODEV here, as in the related failure cases.
gcc has a known bug in underreporting some of these warnings
when it has already eliminated the assignment of the return code
based on some earlier optimization step.
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5712f3301a12c0c3de9cc423484496b0464f2faf ]
The spinlock in the raw3270_view structure is used by con3270, tty3270
and fs3270 in different ways. For con3270 the lock can be acquired in
irq context, for tty3270 and fs3270 the highest context is bh.
Lockdep sees the view->lock as a single class and if the 3270 driver
is used for the console the following message is generated:
WARNING: inconsistent lock state
5.1.0-rc3-05157-g5c168033979d #12 Not tainted
--------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
swapper/0/1 [HC0[0]:SC1[1]:HE1:SE0] takes:
(____ptrval____) (&(&view->lock)->rlock){?.-.}, at: tty3270_update+0x7c/0x330
Introduce a lockdep subclass for the view lock to distinguish bh from
irq locks.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2cc9637ce825f3a9f51f8f78af7474e9e85bfa5f ]
The DASD driver incorrectly limits the maximum number of blocks of ECKD
DASD volumes to 32 bit numbers. Volumes with a capacity greater than
2^32-1 blocks are incorrectly recognized as smaller volumes.
This results in the following volume capacity limits depending on the
formatted block size:
BLKSIZE MAX_GB MAX_CYL
512 2047 5843492
1024 4095 8676701
2048 8191 13634816
4096 16383 23860929
The same problem occurs when a volume with more than 17895697 cylinders
is accessed in raw-track-access mode.
Fix this problem by adding an explicit type cast when calculating the
maximum number of blocks.
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c8206579175c34a2546de8a74262456278a7795a ]
If an incoming ELS of type RSCN contains more than one element, zfcp
suboptimally causes repeated erp trigger NOP trace records for each
previously failed port. These could be ports that went away. It loops over
each RSCN element, and for each of those in an inner loop over all
zfcp_ports.
The trigger to recover failed ports should be just the reception of some
RSCN, no matter how many elements it has. So we can loop over failed ports
separately, and only then loop over each RSCN element to handle the
non-failed ports.
The call chain was:
zfcp_fc_incoming_rscn
for (i = 1; i < no_entries; i++)
_zfcp_fc_incoming_rscn
list_for_each_entry(port, &adapter->port_list, list)
if (masked port->d_id match) zfcp_fc_test_link
if (!port->d_id) zfcp_erp_port_reopen "fcrscn1" <===
In order the reduce the "flooding" of the REC trace area in such cases, we
factor out handling the failed ports to be outside of the entries loop:
zfcp_fc_incoming_rscn
if (no_entries > 1) <===
list_for_each_entry(port, &adapter->port_list, list) <===
if (!port->d_id) zfcp_erp_port_reopen "fcrscn1" <===
for (i = 1; i < no_entries; i++)
_zfcp_fc_incoming_rscn
list_for_each_entry(port, &adapter->port_list, list)
if (masked port->d_id match) zfcp_fc_test_link
Abbreviated example trace records before this code change:
Tag : fcrscn1
WWPN : 0x500507630310d327
ERP want : 0x02
ERP need : 0x02
Tag : fcrscn1
WWPN : 0x500507630310d327
ERP want : 0x02
ERP need : 0x00 NOP => superfluous trace record
The last trace entry repeats if there are more than 2 RSCN elements.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
commit 242ec1455151267fe35a0834aa9038e4c4670884 upstream.
Suppose more than one non-NPIV FCP device is active on the same channel.
Send I/O to storage and have some of the pending I/O run into a SCSI
command timeout, e.g. due to bit errors on the fibre. Now the error
situation stops. However, we saw FCP requests continue to timeout in the
channel. The abort will be successful, but the subsequent TUR fails.
Scsi_eh starts. The LUN reset fails. The target reset fails. The host
reset only did an FCP device recovery. However, for non-NPIV FCP devices,
this does not close and reopen ports on the SAN-side if other non-NPIV FCP
device(s) share the same open ports.
In order to resolve the continuing FCP request timeouts, we need to
explicitly close and reopen ports on the SAN-side.
This was missing since the beginning of zfcp in v2.6.0 history commit
ea127f975424 ("[PATCH] s390 (7/7): zfcp host adapter.").
Note: The FSF requests for forced port reopen could run into FSF request
timeouts due to other reasons. This would trigger an internal FCP device
recovery. Pending forced port reopen recoveries would get dismissed. So
some ports might not get fully reopened during this host reset handler.
However, subsequent I/O would trigger the above described escalation and
eventually all ports would be forced reopen to resolve any continuing FCP
request timeouts due to earlier bit errors.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: <stable@vger.kernel.org> #3.0+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4a8ef6999bce998fa5813023a9a6b56eea329dba ]
Dan Carpenter reported the following:
The patch 52898025cf7d: "[S390] dasd: security and PSF update patch
for EMC CKD ioctl" from Mar 8, 2010, leads to the following static
checker warning:
drivers/s390/block/dasd_eckd.c:4486 dasd_symm_io()
error: using offset into zero size array 'psf_data[]'
drivers/s390/block/dasd_eckd.c
4458 /* Copy parms from caller */
4459 rc = -EFAULT;
4460 if (copy_from_user(&usrparm, argp, sizeof(usrparm)))
^^^^^^^
The user can specify any "usrparm.psf_data_len". They choose zero by
mistake.
4461 goto out;
4462 if (is_compat_task()) {
4463 /* Make sure pointers are sane even on 31 bit. */
4464 rc = -EINVAL;
4465 if ((usrparm.psf_data >> 32) != 0)
4466 goto out;
4467 if ((usrparm.rssd_result >> 32) != 0)
4468 goto out;
4469 usrparm.psf_data &= 0x7fffffffULL;
4470 usrparm.rssd_result &= 0x7fffffffULL;
4471 }
4472 /* alloc I/O data area */
4473 psf_data = kzalloc(usrparm.psf_data_len, GFP_KERNEL
| GFP_DMA);
4474 rssd_result = kzalloc(usrparm.rssd_result_len, GFP_KERNEL
| GFP_DMA);
4475 if (!psf_data || !rssd_result) {
kzalloc() returns a ZERO_SIZE_PTR (0x16).
4476 rc = -ENOMEM;
4477 goto out_free;
4478 }
4479
4480 /* get syscall header from user space */
4481 rc = -EFAULT;
4482 if (copy_from_user(psf_data,
4483 (void __user *)(unsigned long)
usrparm.psf_data,
4484 usrparm.psf_data_len))
That all works great.
4485 goto out_free;
4486 psf0 = psf_data[0];
4487 psf1 = psf_data[1];
But now we're assuming that "->psf_data_len" was at least 2 bytes.
Fix this by checking the user specified length psf_data_len.
Fixes: 52898025cf7d ("[S390] dasd: security and PSF update patch for EMC CKD ioctl")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit afa0c5904ba16d59b0454f7ee4c807dae350f432 ]
The error path in qeth_alloc_qdio_buffers() that takes care of
cleaning up the Output Queues is buggy. It first frees the queue, but
then calls qeth_clear_outq_buffers() with that very queue struct.
Make the call to qeth_clear_outq_buffers() part of the free action
(in the correct order), and while at it fix the naming of the helper.
Fixes: 0da9581ddb0f ("qeth: exploit asynchronous delivery of storage blocks")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit b7cb707c373094ce4008d4a6ac9b6b366ec52da5 upstream.
smp_rescan_cpus() is called without the device_hotplug_lock, which can lead
to a dedlock when a new CPU is found and immediately set online by a udev
rule.
This was observed on an older kernel version, where the cpu_hotplug_begin()
loop was still present, and it resulted in hanging chcpu and systemd-udev
processes. This specific deadlock will not show on current kernels. However,
there may be other possible deadlocks, and since smp_rescan_cpus() can still
trigger a CPU hotplug operation, the device_hotplug_lock should be held.
For reference, this was the deadlock with the old cpu_hotplug_begin() loop:
chcpu (rescan) systemd-udevd
echo 1 > /sys/../rescan
-> smp_rescan_cpus()
-> (*) get_online_cpus()
(increases refcount)
-> smp_add_present_cpu()
(new CPU found)
-> register_cpu()
-> device_add()
-> udev "add" event triggered -----------> udev rule sets CPU online
-> echo 1 > /sys/.../online
-> lock_device_hotplug_sysfs()
(this is missing in rescan path)
-> device_online()
-> (**) device_lock(new CPU dev)
-> cpu_up()
-> cpu_hotplug_begin()
(loops until refcount == 0)
-> deadlock with (*)
-> bus_probe_device()
-> device_attach()
-> device_lock(new CPU dev)
-> deadlock with (**)
Fix this by taking the device_hotplug_lock in the CPU rescan path.
Cc: <stable@vger.kernel.org>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 60a161b7e5b2a252ff0d4c622266a7d8da1120ce upstream.
Suppose adapter (open) recovery is between opened QDIO queues and before
(the end of) initial posting of status read buffers (SRBs). This time
window can be seconds long due to FSF_PROT_HOST_CONNECTION_INITIALIZING
causing by design looping with exponential increase sleeps in the function
performing exchange config data during recovery
[zfcp_erp_adapter_strat_fsf_xconf()]. Recovery triggered by local link up.
Suppose an event occurs for which the FCP channel would send an unsolicited
notification to zfcp by means of a previously posted SRB. We saw it with
local cable pull (link down) in multi-initiator zoning with multiple
NPIV-enabled subchannels of the same shared FCP channel.
As soon as zfcp_erp_adapter_strategy_open_fsf() starts posting the initial
status read buffers from within the adapter's ERP thread, the channel does
send an unsolicited notification.
Since v2.6.27 commit d26ab06ede83 ("[SCSI] zfcp: receiving an unsolicted
status can lead to I/O stall"), zfcp_fsf_status_read_handler() schedules
adapter->stat_work to re-fill the just consumed SRB from a work item.
Now the ERP thread and the work item post SRBs in parallel. Both contexts
call the helper function zfcp_status_read_refill(). The tracking of
missing (to be posted / re-filled) SRBs is not thread-safe due to separate
atomic_read() and atomic_dec(), in order to depend on posting
success. Hence, both contexts can see
atomic_read(&adapter->stat_miss) == 1. One of the two contexts posts
one too many SRB. Zfcp gets QDIO_ERROR_SLSB_STATE on the output queue
(trace tag "qdireq1") leading to zfcp_erp_adapter_shutdown() in
zfcp_qdio_handler_error().
An obvious and seemingly clean fix would be to schedule stat_work from the
ERP thread and wait for it to finish. This would serialize all SRB
re-fills. However, we already have another work item wait on the ERP
thread: adapter->scan_work runs zfcp_fc_scan_ports() which calls
zfcp_fc_eval_gpn_ft(). The latter calls zfcp_erp_wait() to wait for all the
open port recoveries during zfcp auto port scan, but in fact it waits for
any pending recovery including an adapter recovery. This approach leads to
a deadlock. [see also v3.19 commit 18f87a67e6d6 ("zfcp: auto port scan
resiliency"); v2.6.37 commit d3e1088d6873
("[SCSI] zfcp: No ERP escalation on gpn_ft eval");
v2.6.28 commit fca55b6fb587
("[SCSI] zfcp: fix deadlock between wq triggered port scan and ERP")
fixing v2.6.27 commit c57a39a45a76
("[SCSI] zfcp: wait until adapter is finished with ERP during auto-port");
v2.6.27 commit cc8c282963bd
("[SCSI] zfcp: Automatically attach remote ports")]
Instead make the accounting of missing SRBs atomic for parallel execution
in both the ERP thread and adapter->stat_work.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: d26ab06ede83 ("[SCSI] zfcp: receiving an unsolicted status can lead to I/O stall")
Cc: <stable@vger.kernel.org> #2.6.27+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9a764c1e59684c0358e16ccaafd870629f2cfe67 ]
The response for a SNMP request can consist of multiple parts, which
the cmd callback stages into a kernel buffer until all parts have been
received. If the callback detects that the staging buffer provides
insufficient space, it bails out with error.
This processing is buggy for the first part of the response - while it
initially checks for a length of 'data_len', it later copies an
additional amount of 'offsetof(struct qeth_snmp_cmd, data)' bytes.
Fix the calculation of 'data_len' for the first part of the response.
This also nicely cleans up the memcpy code.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>