2719 Commits

Author SHA1 Message Date
Steffen Maier 4b106b91a0 scsi: zfcp: trace HBA FSF response by default on dismiss or timedout late response
commit fdb7cee3b9e3c561502e58137a837341f10cbf8b upstream.

At the default trace level, we only trace unsuccessful events including
FSF responses.

zfcp_dbf_hba_fsf_response() only used protocol status and FSF status to
decide on an unsuccessful response. However, this is only one of multiple
possible sources determining a failed struct zfcp_fsf_req.

An FSF request can also "fail" if its response runs into an ERP timeout
or if it gets dismissed because a higher level recovery was triggered
[trace tags "erscf_1" or "erscf_2" in zfcp_erp_strategy_check_fsfreq()].
FSF requests with ERP timeout are:
FSF_QTCB_EXCHANGE_CONFIG_DATA, FSF_QTCB_EXCHANGE_PORT_DATA,
FSF_QTCB_OPEN_PORT_WITH_DID or FSF_QTCB_CLOSE_PORT or
FSF_QTCB_CLOSE_PHYSICAL_PORT for target ports,
FSF_QTCB_OPEN_LUN, FSF_QTCB_CLOSE_LUN.
One example is slow queue processing which can cause follow-on errors,
e.g. FSF_PORT_ALREADY_OPEN after FSF_QTCB_OPEN_PORT_WITH_DID timed out.
In order to see the root cause, we need to see late responses even if the
channel presented them successfully with FSF_PROT_GOOD and FSF_GOOD.
Example trace records formatted with zfcpdbf from the s390-tools package:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : ...
Record ID      : 1
Tag            : fcegpf1
LUN            : 0xffffffffffffffff
WWPN           : 0x<WWPN>
D_ID           : 0x00<D_ID>
Adapter status : 0x5400050b
Port status    : 0x41200000
LUN status     : 0x00000000
Ready count    : 0x00000001
Running count  : 0x...
ERP want       : 0x02				ZFCP_ERP_ACTION_REOPEN_PORT
ERP need       : 0x02				ZFCP_ERP_ACTION_REOPEN_PORT
|
Timestamp      : ...				30 seconds later
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : ...
Record ID      : 2
Tag            : erscf_2
LUN            : 0xffffffffffffffff
WWPN           : 0x<WWPN>
D_ID           : 0x00<D_ID>
Adapter status : 0x5400050b
Port status    : 0x41200000
LUN status     : 0x00000000
Request ID     : 0x<request_ID>
ERP status     : 0x10000000			ZFCP_STATUS_ERP_TIMEDOUT
ERP step       : 0x0800				ZFCP_ERP_STEP_PORT_OPENING
ERP action     : 0x02				ZFCP_ERP_ACTION_REOPEN_PORT
ERP count      : 0x00
|
Timestamp      : ...				later than previous record
Area           : HBA
Subarea        : 00
Level          : 5	> default level		=> 3	<= default level
Exception      : -
CPU ID         : 00
Caller         : ...
Record ID      : 1
Tag            : fs_qtcb			=> fs_rerr
Request ID     : 0x<request_ID>
Request status : 0x00001010			ZFCP_STATUS_FSFREQ_DISMISSED
						| ZFCP_STATUS_FSFREQ_CLEANUP
FSF cmnd       : 0x00000005
FSF sequence no: 0x...
FSF issued     : ...				> 30 seconds ago
FSF stat       : 0x00000000			FSF_GOOD
FSF stat qual  : 00000000 00000000 00000000 00000000
Prot stat      : 0x00000001			FSF_PROT_GOOD
Prot stat qual : 00000000 00000000 00000000 00000000
Port handle    : 0x...
LUN handle     : 0x00000000
QTCB log length: ...
QTCB log info  : ...

In case of problems detecting that new responses are waiting on the input
queue, we sooner or later trigger adapter recovery due to an FSF request
timeout (trace tag "fsrth_1").
FSF requests with FSF request timeout are:
typically FSF_QTCB_ABORT_FCP_CMND; but theoretically also
FSF_QTCB_EXCHANGE_CONFIG_DATA or FSF_QTCB_EXCHANGE_PORT_DATA via sysfs,
FSF_QTCB_OPEN_PORT_WITH_DID or FSF_QTCB_CLOSE_PORT for WKA ports,
FSF_QTCB_FCP_CMND for task management function (LUN / target reset).
One or more pending requests can meanwhile have FSF_PROT_GOOD and FSF_GOOD
because the channel filled in the response via DMA into the request's QTCB.

In a theroretical case, inject code can create an erroneous FSF request
on purpose. If data router is enabled, it uses deferred error reporting.
A READ SCSI command can succeed with FSF_PROT_GOOD, FSF_GOOD, and
SAM_STAT_GOOD. But on writing the read data to host memory via DMA,
it can still fail, e.g. if an intentionally wrong scatter list does not
provide enough space. Rather than getting an unsuccessful response,
we get a QDIO activate check which in turn triggers adapter recovery.
One or more pending requests can meanwhile have FSF_PROT_GOOD and FSF_GOOD
because the channel filled in the response via DMA into the request's QTCB.
Example trace records formatted with zfcpdbf from the s390-tools package:

Timestamp      : ...
Area           : HBA
Subarea        : 00
Level          : 6	> default level		=> 3	<= default level
Exception      : -
CPU ID         : ..
Caller         : ...
Record ID      : 1
Tag            : fs_norm			=> fs_rerr
Request ID     : 0x<request_ID2>
Request status : 0x00001010			ZFCP_STATUS_FSFREQ_DISMISSED
						| ZFCP_STATUS_FSFREQ_CLEANUP
FSF cmnd       : 0x00000001
FSF sequence no: 0x...
FSF issued     : ...
FSF stat       : 0x00000000			FSF_GOOD
FSF stat qual  : 00000000 00000000 00000000 00000000
Prot stat      : 0x00000001			FSF_PROT_GOOD
Prot stat qual : ........ ........ 00000000 00000000
Port handle    : 0x...
LUN handle     : 0x...
|
Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 3
Exception      : -
CPU ID         : ..
Caller         : ...
Record ID      : 1
Tag            : rsl_err
Request ID     : 0x<request_ID2>
SCSI ID        : 0x...
SCSI LUN       : 0x...
SCSI result    : 0x000e0000			DID_TRANSPORT_DISRUPTED
SCSI retries   : 0x00
SCSI allowed   : 0x05
SCSI scribble  : 0x<request_ID2>
SCSI opcode    : 28...				Read(10)
FCP rsp inf cod: 0x00
FCP rsp IU     : 00000000 00000000 00000000 00000000
                                         ^^	SAM_STAT_GOOD
                 00000000 00000000

Only with luck in both above cases, we could see a follow-on trace record
of an unsuccesful event following a successful but late FSF response with
FSF_PROT_GOOD and FSF_GOOD. Typically this was the case for I/O requests
resulting in a SCSI trace record "rsl_err" with DID_TRANSPORT_DISRUPTED
[On ZFCP_STATUS_FSFREQ_DISMISSED, zfcp_fsf_protstatus_eval() sets
ZFCP_STATUS_FSFREQ_ERROR seen by the request handler functions as failure].
However, the reason for this follow-on trace was invisible because the
corresponding HBA trace record was missing at the default trace level
(by default hidden records with tags "fs_norm", "fs_qtcb", or "fs_open").

On adapter recovery, after we had shut down the QDIO queues, we perform
unsuccessful pseudo completions with flag ZFCP_STATUS_FSFREQ_DISMISSED
for each pending FSF request in zfcp_fsf_req_dismiss_all().
In order to find the root cause, we need to see all pseudo responses even
if the channel presented them successfully with FSF_PROT_GOOD and FSF_GOOD.

Therefore, check zfcp_fsf_req.status for ZFCP_STATUS_FSFREQ_DISMISSED
or ZFCP_STATUS_FSFREQ_ERROR and trace with a new tag "fs_rerr".

It does not matter that there are numerous places which set
ZFCP_STATUS_FSFREQ_ERROR after the location where we trace an FSF response
early. These cases are based on protocol status != FSF_PROT_GOOD or
== FSF_PROT_FSF_STATUS_PRESENTED and are thus already traced by default
as trace tag "fs_perr" or "fs_ferr" respectively.

NB: The trace record with tag "fssrh_1" for status read buffers on dismiss
all remains. zfcp_fsf_req_complete() handles this and returns early.
All other FSF request types are handled separately and as described above.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 8a36e4532e ("[SCSI] zfcp: enhancement of zfcp debug features")
Fixes: 2e261af84c ("[SCSI] zfcp: Only collect FSF/HBA debug data for matching trace levels")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-11-02 07:09:50 +01:00
Steffen Maier bb5cf573ea scsi: zfcp: fix payload with full FCP_RSP IU in SCSI trace records
commit 12c3e5754c8022a4f2fd1e9f00d19e99ee0d3cc1 upstream.

If the FCP_RSP UI has optional parts (FCP_SNS_INFO or FCP_RSP_INFO) and
thus does not fit into the fsp_rsp field built into a SCSI trace record,
trace the full FCP_RSP UI with all optional parts as payload record
instead of just FCP_SNS_INFO as payload and
a 1 byte RSP_INFO_CODE part of FCP_RSP_INFO built into the SCSI record.

That way we would also get the full FCP_SNS_INFO in case a
target would ever send more than
min(SCSI_SENSE_BUFFERSIZE==96, ZFCP_DBF_PAY_MAX_REC==256)==96.

The mandatory part of FCP_RSP IU is only 24 bytes.
PAYload costs at least one full PAY record of 256 bytes anyway.
We cap to the hardware response size which is only FSF_FCP_RSP_SIZE==128.
So we can just put the whole FCP_RSP IU with any optional parts into
PAYload similarly as we do for SAN PAY since v4.9 commit aceeffbb59bb
("zfcp: trace full payload of all SAN records (req,resp,iels)").
This does not cause any additional trace records wasting memory.

Decoded trace records were confusing because they showed a hard-coded
sense data length of 96 even if the FCP_RSP_IU field FCP_SNS_LEN showed
actually less.

Since the same commit, we set pl_len for SAN traces to the full length of a
request/response even if we cap the corresponding trace.
In contrast, here for SCSI traces we set pl_len to the pre-computed
length of FCP_RSP IU considering SNS_LEN or RSP_LEN if valid.
Nonetheless we trace a hardcoded payload of length FSF_FCP_RSP_SIZE==128
if there were optional parts.
This makes it easier for the zfcpdbf tool to format only the relevant
part of the long FCP_RSP UI buffer. And any trailing information is still
available in the payload trace record just in case.

Rename the payload record tag from "fcp_sns" to "fcp_riu" to make the new
content explicit to zfcpdbf which can then pick a suitable field name such
as "FCP rsp IU all:" instead of "Sense info :"
Also, the same zfcpdbf can still be backwards compatible with "fcp_sns".

Old example trace record before this fix, formatted with the tool zfcpdbf
from s390-tools:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 3
Exception      : -
CPU id         : ..
Caller         : 0x...
Record id      : 1
Tag            : rsl_err
Request id     : 0x<request_id>
SCSI ID        : 0x...
SCSI LUN       : 0x...
SCSI result    : 0x00000002
SCSI retries   : 0x00
SCSI allowed   : 0x05
SCSI scribble  : 0x<request_id>
SCSI opcode    : 00000000 00000000 00000000 00000000
FCP rsp inf cod: 0x00
FCP rsp IU     : 00000000 00000000 00000202 00000000
                                       ^^==FCP_SNS_LEN_VALID
                 00000020 00000000
                 ^^^^^^^^==FCP_SNS_LEN==32
Sense len      : 96 <==min(SCSI_SENSE_BUFFERSIZE,ZFCP_DBF_PAY_MAX_REC)
Sense info     : 70000600 00000018 00000000 29000000
                 00000400 00000000 00000000 00000000
                 00000000 00000000 00000000 00000000<==superfluous
                 00000000 00000000 00000000 00000000<==superfluous
                 00000000 00000000 00000000 00000000<==superfluous
                 00000000 00000000 00000000 00000000<==superfluous

New example trace records with this fix:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 3
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : rsl_err
Request ID     : 0x<request_id>
SCSI ID        : 0x...
SCSI LUN       : 0x...
SCSI result    : 0x00000002
SCSI retries   : 0x00
SCSI allowed   : 0x03
SCSI scribble  : 0x<request_id>
SCSI opcode    : a30c0112 00000000 02000000 00000000
FCP rsp inf cod: 0x00
FCP rsp IU     : 00000000 00000000 00000a02 00000200
                 00000020 00000000
FCP rsp IU len : 56
FCP rsp IU all : 00000000 00000000 00000a02 00000200
                                       ^^=FCP_RESID_UNDER|FCP_SNS_LEN_VALID
                 00000020 00000000 70000500 00000018
                 ^^^^^^^^==FCP_SNS_LEN
                                   ^^^^^^^^^^^^^^^^^
                 00000000 240000cb 00011100 00000000
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                 00000000 00000000
                 ^^^^^^^^^^^^^^^^^==FCP_SNS_INFO

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : lr_okay
Request ID     : 0x<request_id>
SCSI ID        : 0x...
SCSI LUN       : 0x...
SCSI result    : 0x00000000
SCSI retries   : 0x00
SCSI allowed   : 0x05
SCSI scribble  : 0x<request_id>
SCSI opcode    : <CDB of unrelated SCSI command passed to eh handler>
FCP rsp inf cod: 0x00
FCP rsp IU     : 00000000 00000000 00000100 00000000
                 00000000 00000008
FCP rsp IU len : 32
FCP rsp IU all : 00000000 00000000 00000100 00000000
                                       ^^==FCP_RSP_LEN_VALID
                 00000000 00000008 00000000 00000000
                          ^^^^^^^^==FCP_RSP_LEN
                                   ^^^^^^^^^^^^^^^^^==FCP_RSP_INFO

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 250a1352b9 ("[SCSI] zfcp: Redesign of the debug tracing for SCSI records.")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-11-02 07:09:49 +01:00
Steffen Maier 2c7bfb3408 scsi: zfcp: fix missing trace records for early returns in TMF eh handlers
commit 1a5d999ebfc7bfe28deb48931bb57faa8e4102b6 upstream.

For problem determination we need to see that we were in scsi_eh
as well as whether and why we were successful or not.

The following commits introduced new early returns without adding
a trace record:

v2.6.35 commit a1dbfddd02
("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh")
on fc_block_scsi_eh() returning != 0 which is FAST_IO_FAIL,

v2.6.30 commit 63caf367e1
("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp")
on not having gotten an FSF request after the maximum number of retry
attempts and thus could not issue a TMF and has to return FAILED.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: a1dbfddd02 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh")
Fixes: 63caf367e1 ("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-11-02 07:09:44 +01:00
Benjamin Block e7ab3bd99e scsi: zfcp: add handling for FCP_RESID_OVER to the fcp ingress path
commit a099b7b1fc1f0418ab8d79ecf98153e1e134656e upstream.

Up until now zfcp would just ignore the FCP_RESID_OVER flag in the FCP
response IU. When this flag is set, it is possible, in regards to the
FCP standard, that the storage-server processes the command normally, up
to the point where data is missing and simply ignores those.

In this case no CHECK CONDITION would be set, and because we ignored the
FCP_RESID_OVER flag we resulted in at least a data loss or even
-corruption as a follow-up error, depending on how the
applications/layers on top behave. To prevent this, we now set the
host-byte of the corresponding scsi_cmnd to DID_ERROR.

Other storage-behaviors, where the same condition results in a CHECK
CONDITION set in the answer, don't need to be changed as they are
handled in the mid-layer already.

Following is an example trace record decoded with zfcpdbf from the
s390-tools package. We forcefully injected a fc_dl which is one byte too
small:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 3
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : rsl_err
Request ID     : 0x...
SCSI ID        : 0x...
SCSI LUN       : 0x...
SCSI result    : 0x00070000
                     ^^DID_ERROR
SCSI retries   : 0x..
SCSI allowed   : 0x..
SCSI scribble  : 0x...
SCSI opcode    : 2a000000 00000000 08000000 00000000
FCP rsp inf cod: 0x00
FCP rsp IU     : 00000000 00000000 00000400 00000001
                                       ^^fr_flags==FCP_RESID_OVER
                                         ^^fr_status==SAM_STAT_GOOD
                                            ^^^^^^^^fr_resid
                 00000000 00000000

As of now, we don't actively handle to possibility that a response IU
has both flags - FCP_RESID_OVER and FCP_RESID_UNDER - set at once.

Reported-by: Luke M. Hopkins <lmhopkin@us.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 553448f6c4 ("[SCSI] zfcp: Message cleanup")
Fixes: ea127f975424 ("[PATCH] s390 (7/7): zfcp host adapter.") (tglx/history.git)
Cc: <stable@vger.kernel.org> #2.6.33+
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-11-01 22:12:44 +01:00
Steffen Maier f609dac650 scsi: zfcp: fix queuecommand for scsi_eh commands when DIX enabled
commit 71b8e45da51a7b64a23378221c0a5868bd79da4f upstream.

Since commit db007fc5e2 ("[SCSI] Command protection operation"),
scsi_eh_prep_cmnd() saves scmd->prot_op and temporarily resets it to
SCSI_PROT_NORMAL.
Other FCP LLDDs such as qla2xxx and lpfc shield their queuecommand()
to only access any of scsi_prot_sg...() if
(scsi_get_prot_op(cmd) != SCSI_PROT_NORMAL).

Do the same thing for zfcp, which introduced DIX support with
commit ef3eb71d8b ("[SCSI] zfcp: Introduce experimental support for
DIF/DIX").

Otherwise, TUR SCSI commands as part of scsi_eh likely fail in zfcp,
because the regular SCSI command with DIX protection data, that scsi_eh
re-uses in scsi_send_eh_cmnd(), of course still has
(scsi_prot_sg_count() != 0) and so zfcp sends down bogus requests to the
FCP channel hardware.

This causes scsi_eh_test_devices() to have (finish_cmds == 0)
[not SCSI device is online or not scsi_eh_tur() failed]
so regular SCSI commands, that caused / were affected by scsi_eh,
are moved to work_q and scsi_eh_test_devices() itself returns false.
In turn, it unnecessarily escalates in our case in scsi_eh_ready_devs()
beyond host reset to finally scsi_eh_offline_sdevs()
which sets affected SCSI devices offline with the following kernel message:

"kernel: sd H:0:T:L: Device offlined - not ready after error recovery"

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: ef3eb71d8b ("[SCSI] zfcp: Introduce experimental support for DIF/DIX")
Cc: <stable@vger.kernel.org> #2.6.36+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-11-01 22:12:44 +01:00
Gerald Schaefer 8cfc539f62 s390/vmlogrdr: fix IUCV buffer allocation
commit 5457e03de918f7a3e294eb9d26a608ab8a579976 upstream.

The buffer for iucv_message_receive() needs to be below 2 GB. In
__iucv_message_receive(), the buffer address is casted to an u32, which
would result in either memory corruption or an addressing exception when
using addresses >= 2 GB.

Fix this by using GFP_DMA for the buffer allocation.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-06-20 14:03:24 +02:00
Julian Wiedmann 8e68a4d13a s390/qdio: clear DSCI prior to scanning multiple input queues
commit 1e4a382fdc0ba8d1a85b758c0811de3a3631085e upstream.

For devices with multiple input queues, tiqdio_call_inq_handlers()
iterates over all input queues and clears the device's DSCI
during each iteration. If the DSCI is re-armed during one
of the later iterations, we therefore do not scan the previous
queues again.
The re-arming also raises a new adapter interrupt. But its
handler does not trigger a rescan for the device, as the DSCI
has already been erroneously cleared.
This can result in queue stalls on devices with multiple
input queues.

Fix it by clearing the DSCI just once, prior to scanning the queues.

As the code is moved in front of the loop, we also need to access
the DSCI directly (ie irq->dsci) instead of going via each queue's
parent pointer to the same irq. This is not a functional change,
and a follow-up patch will clean up the other users.

In practice, this bug only affects CQ-enabled HiperSockets devices,
ie. devices with sysfs-attribute "hsuid" set. Setting a hsuid is
needed for AF_IUCV socket applications that use HiperSockets
communication.

Fixes: 104ea556ee ("qdio: support asynchronous delivery of storage blocks")
Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-06-08 00:47:02 +02:00
Steffen Maier 01e26ca64b scsi: zfcp: fix use-after-free by not tracing WKA port open/close on failed send
commit 2dfa6688aafdc3f74efeb1cf05fb871465d67f79 upstream.

Dan Carpenter kindly reported:
<quote>
The patch d27a7cb91960: "zfcp: trace on request for open and close of
WKA port" from Aug 10, 2016, leads to the following static checker
warning:

	drivers/s390/scsi/zfcp_fsf.c:1615 zfcp_fsf_open_wka_port()
	warn: 'req' was already freed.

drivers/s390/scsi/zfcp_fsf.c
  1609          zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
  1610          retval = zfcp_fsf_req_send(req);
  1611          if (retval)
  1612                  zfcp_fsf_req_free(req);
                                          ^^^
Freed.

  1613  out:
  1614          spin_unlock_irq(&qdio->req_q_lock);
  1615          if (req && !IS_ERR(req))
  1616                  zfcp_dbf_rec_run_wka("fsowp_1", wka_port, req->req_id);
                                                                  ^^^^^^^^^^^
Use after free.

  1617          return retval;
  1618  }

Same thing for zfcp_fsf_close_wka_port() as well.
</quote>

Rather than relying on req being NULL (or ERR_PTR) for all cases where
we don't want to trace or should not trace,
simply check retval which is unconditionally initialized with -EIO != 0
and it can only become 0 on successful retval = zfcp_fsf_req_send(req).
With that we can also remove the then again unnecessary unconditional
initialization of req which was introduced with that earlier commit.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Suggested-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: d27a7cb91960 ("zfcp: trace on request for open and close of WKA port")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-06-08 00:46:58 +02:00
Steffen Maier 1c2287b99f scsi: zfcp: fix rport unblock race with LUN recovery
commit 6f2ce1c6af37191640ee3ff6e8fc39ea10352f4c upstream.

It is unavoidable that zfcp_scsi_queuecommand() has to finish requests
with DID_IMM_RETRY (like fc_remote_port_chkready()) during the time
window when zfcp detected an unavailable rport but
fc_remote_port_delete(), which is asynchronous via
zfcp_scsi_schedule_rport_block(), has not yet blocked the rport.

However, for the case when the rport becomes available again, we should
prevent unblocking the rport too early.  In contrast to other FCP LLDDs,
zfcp has to open each LUN with the FCP channel hardware before it can
send I/O to a LUN.  So if a port already has LUNs attached and we
unblock the rport just after port recovery, recoveries of LUNs behind
this port can still be pending which in turn force
zfcp_scsi_queuecommand() to unnecessarily finish requests with
DID_IMM_RETRY.

This also opens a time window with unblocked rport (until the followup
LUN reopen recovery has finished).  If a scsi_cmnd timeout occurs during
this time window fc_timed_out() cannot work as desired and such command
would indeed time out and trigger scsi_eh. This prevents a clean and
timely path failover.  This should not happen if the path issue can be
recovered on FC transport layer such as path issues involving RSCNs.

Fix this by only calling zfcp_scsi_schedule_rport_register(), to
asynchronously trigger fc_remote_port_add(), after all LUN recoveries as
children of the rport have finished and no new recoveries of equal or
higher order were triggered meanwhile.  Finished intentionally includes
any recovery result no matter if successful or failed (still unblock
rport so other successful LUNs work).  For simplicity, we check after
each finished LUN recovery if there is another LUN recovery pending on
the same port and then do nothing.  We handle the special case of a
successful recovery of a port without LUN children the same way without
changing this case's semantics.

For debugging we introduce 2 new trace records written if the rport
unblock attempt was aborted due to still unfinished or freshly triggered
recovery. The records are only written above the default trace level.

Benjamin noticed the important special case of new recovery that can be
triggered between having given up the erp_lock and before calling
zfcp_erp_action_cleanup() within zfcp_erp_strategy().  We must avoid the
following sequence:

ERP thread                 rport_work      other context
-------------------------  --------------  --------------------------------
port is unblocked, rport still blocked,
 due to pending/running ERP action,
 so ((port->status & ...UNBLOCK) != 0)
 and (port->rport == NULL)
unlock ERP
zfcp_erp_action_cleanup()
case ZFCP_ERP_ACTION_REOPEN_LUN:
zfcp_erp_try_rport_unblock()
((status & ...UNBLOCK) != 0) [OLD!]
                                           zfcp_erp_port_reopen()
                                           lock ERP
                                           zfcp_erp_port_block()
                                           port->status clear ...UNBLOCK
                                           unlock ERP
                                           zfcp_scsi_schedule_rport_block()
                                           port->rport_task = RPORT_DEL
                                           queue_work(rport_work)
                           zfcp_scsi_rport_work()
                           (port->rport_task != RPORT_ADD)
                           port->rport_task = RPORT_NONE
                           zfcp_scsi_rport_block()
                           if (!port->rport) return
zfcp_scsi_schedule_rport_register()
port->rport_task = RPORT_ADD
queue_work(rport_work)
                           zfcp_scsi_rport_work()
                           (port->rport_task == RPORT_ADD)
                           port->rport_task = RPORT_NONE
                           zfcp_scsi_rport_register()
                           (port->rport == NULL)
                           rport = fc_remote_port_add()
                           port->rport = rport;

Now the rport was erroneously unblocked while the zfcp_port is blocked.
This is another situation we want to avoid due to scsi_eh
potential. This state would at least remain until the new recovery from
the other context finished successfully, or potentially forever if it
failed.  In order to close this race, we take the erp_lock inside
zfcp_erp_try_rport_unblock() when checking the status of zfcp_port or
LUN.  With that, the possible corresponding rport state sequences would
be: (unblock[ERP thread],block[other context]) if the ERP thread gets
erp_lock first and still sees ((port->status & ...UNBLOCK) != 0),
(block[other context],NOP[ERP thread]) if the ERP thread gets erp_lock
after the other context has already cleard ...UNBLOCK from port->status.

Since checking fields of struct erp_action is unsafe because they could
have been overwritten (re-used for new recovery) meanwhile, we only
check status of zfcp_port and LUN since these are only changed under
erp_lock elsewhere. Regarding the check of the proper status flags (port
or port_forced are similar to the shown adapter recovery):

[zfcp_erp_adapter_shutdown()]
zfcp_erp_adapter_reopen()
 zfcp_erp_adapter_block()
  * clear UNBLOCK ---------------------------------------+
 zfcp_scsi_schedule_rports_block()                       |
 write_lock_irqsave(&adapter->erp_lock, flags);-------+  |
 zfcp_erp_action_enqueue()                            |  |
  zfcp_erp_setup_act()                                |  |
   * set ERP_INUSE -----------------------------------|--|--+
 write_unlock_irqrestore(&adapter->erp_lock, flags);--+  |  |
.context-switch.                                         |  |
zfcp_erp_thread()                                        |  |
 zfcp_erp_strategy()                                     |  |
  write_lock_irqsave(&adapter->erp_lock, flags);------+  |  |
  ...                                                 |  |  |
  zfcp_erp_strategy_check_target()                    |  |  |
   zfcp_erp_strategy_check_adapter()                  |  |  |
    zfcp_erp_adapter_unblock()                        |  |  |
     * set UNBLOCK -----------------------------------|--+  |
  zfcp_erp_action_dequeue()                           |     |
   * clear ERP_INUSE ---------------------------------|-----+
  ...                                                 |
  write_unlock_irqrestore(&adapter->erp_lock, flags);-+

Hence, we should check for both UNBLOCK and ERP_INUSE because they are
interleaved.  Also we need to explicitly check ERP_FAILED for the link
down case which currently does not clear the UNBLOCK flag in
zfcp_fsf_link_down_info_eval().

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 8830271c48 ("[SCSI] zfcp: Dont fail SCSI commands when transitioning to blocked fc_rport")
Fixes: a2fa0aede0 ("[SCSI] zfcp: Block FC transport rports early on errors")
Fixes: 5f852be9e1 ("[SCSI] zfcp: Fix deadlock between zfcp ERP and SCSI")
Fixes: 338151e066 ("[SCSI] zfcp: make use of fc_remote_port_delete when target port is unavailable")
Fixes: 3859f6a248 ("[PATCH] zfcp: add rports to enable scsi_add_device to work again")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-06-08 00:46:49 +02:00
Steffen Maier 5d35a96311 scsi: zfcp: do not trace pure benign residual HBA responses at default level
commit 56d23ed7adf3974f10e91b643bd230e9c65b5f79 upstream.

Since quite a while, Linux issues enough SCSI commands per scsi_device
which successfully return with FCP_RESID_UNDER, FSF_FCP_RSP_AVAILABLE,
and SAM_STAT_GOOD.  This floods the HBA trace area and we cannot see
other and important HBA trace records long enough.

Therefore, do not trace HBA response errors for pure benign residual
under counts at the default trace level.

This excludes benign residual under count combined with other validity
bits set in FCP_RSP_IU, such as FCP_SNS_LEN_VAL.  For all those other
cases, we still do want to see both the HBA record and the corresponding
SCSI record by default.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-06-08 00:46:49 +02:00
Benjamin Block 54539504f0 scsi: zfcp: fix use-after-"free" in FC ingress path after TMF
commit dac37e15b7d511e026a9313c8c46794c144103cd upstream.

When SCSI EH invokes zFCP's callbacks for eh_device_reset_handler() and
eh_target_reset_handler(), it expects us to relent the ownership over
the given scsi_cmnd and all other scsi_cmnds within the same scope - LUN
or target - when returning with SUCCESS from the callback ('release'
them).  SCSI EH can then reuse those commands.

We did not follow this rule to release commands upon SUCCESS; and if
later a reply arrived for one of those supposed to be released commands,
we would still make use of the scsi_cmnd in our ingress tasklet. This
will at least result in undefined behavior or a kernel panic because of
a wrong kernel pointer dereference.

To fix this, we NULLify all pointers to scsi_cmnds (struct zfcp_fsf_req
*)->data in the matching scope if a TMF was successful. This is done
under the locks (struct zfcp_adapter *)->abort_lock and (struct
zfcp_reqlist *)->lock to prevent the requests from being removed from
the request-hashtable, and the ingress tasklet from making use of the
scsi_cmnd-pointer in zfcp_fsf_fcp_cmnd_handler().

For cases where a reply arrives during SCSI EH, but before we get a
chance to NULLify the pointer - but before we return from the callback
-, we assume that the code is protected from races via the CAS operation
in blk_complete_request() that is called in scsi_done().

The following stacktrace shows an example for a crash resulting from the
previous behavior:

Unable to handle kernel pointer dereference at virtual kernel address fffffee17a672000
Oops: 0038 [#1] SMP
CPU: 2 PID: 0 Comm: swapper/2 Not tainted
task: 00000003f7ff5be0 ti: 00000003f3d38000 task.ti: 00000003f3d38000
Krnl PSW : 0404d00180000000 00000000001156b0 (smp_vcpu_scheduled+0x18/0x40)
           R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
Krnl GPRS: 000000200000007e 0000000000000000 fffffee17a671fd8 0000000300000015
           ffffffff80000000 00000000005dfde8 07000003f7f80e00 000000004fa4e800
           000000036ce8d8f8 000000036ce8d9c0 00000003ece8fe00 ffffffff969c9e93
           00000003fffffffd 000000036ce8da10 00000000003bf134 00000003f3b07918
Krnl Code: 00000000001156a2: a7190000        lghi    %r1,0
           00000000001156a6: a7380015        lhi    %r3,21
          #00000000001156aa: e32050000008    ag    %r2,0(%r5)
          >00000000001156b0: 482022b0        lh    %r2,688(%r2)
           00000000001156b4: ae123000        sigp    %r1,%r2,0(%r3)
           00000000001156b8: b2220020        ipm    %r2
           00000000001156bc: 8820001c        srl    %r2,28
           00000000001156c0: c02700000001    xilf    %r2,1
Call Trace:
([<0000000000000000>] 0x0)
 [<000003ff807bdb8e>] zfcp_fsf_fcp_cmnd_handler+0x3de/0x490 [zfcp]
 [<000003ff807be30a>] zfcp_fsf_req_complete+0x252/0x800 [zfcp]
 [<000003ff807c0a48>] zfcp_fsf_reqid_check+0xe8/0x190 [zfcp]
 [<000003ff807c194e>] zfcp_qdio_int_resp+0x66/0x188 [zfcp]
 [<000003ff80440c64>] qdio_kick_handler+0xdc/0x310 [qdio]
 [<000003ff804463d0>] __tiqdio_inbound_processing+0xf8/0xcd8 [qdio]
 [<0000000000141fd4>] tasklet_action+0x9c/0x170
 [<0000000000141550>] __do_softirq+0xe8/0x258
 [<000000000010ce0a>] do_softirq+0xba/0xc0
 [<000000000014187c>] irq_exit+0xc4/0xe8
 [<000000000046b526>] do_IRQ+0x146/0x1d8
 [<00000000005d6a3c>] io_return+0x0/0x8
 [<00000000005d6422>] vtime_stop_cpu+0x4a/0xa0
([<0000000000000000>] 0x0)
 [<0000000000103d8a>] arch_cpu_idle+0xa2/0xb0
 [<0000000000197f94>] cpu_startup_entry+0x13c/0x1f8
 [<0000000000114782>] smp_start_secondary+0xda/0xe8
 [<00000000005d6efe>] restart_int_handler+0x56/0x6c
 [<0000000000000000>] 0x0
Last Breaking-Event-Address:
 [<00000000003bf12e>] arch_spin_lock_wait+0x56/0xb0

Suggested-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Fixes: ea127f9754 ("[PATCH] s390 (7/7): zfcp host adapter.") (tglx/history.git)
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-06-08 00:46:49 +02:00
Dan Carpenter 7ddb258493 scsi: zfcp: spin_lock_irqsave() is not nestable
commit e7cb08e894a0b876443ef8fdb0706575dc00a5d2 upstream.

We accidentally overwrite the original saved value of "flags" so that we
can't re-enable IRQs at the end of the function.  Presumably this
function is mostly called with IRQs disabled or it would be obvious in
testing.

Fixes: aceeffbb59bb ("zfcp: trace full payload of all SAN records (req,resp,iels)")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:13 +01:00
Steffen Maier beb0b6c9a7 zfcp: trace full payload of all SAN records (req,resp,iels)
commit aceeffbb59bb91404a0bda32a542d7ebf878433a upstream.

This was lost with commit 2c55b750a8
("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
but is necessary for problem determination, e.g. to see the
currently active zone set during automatic port scan.

For the large GPN_FT response (4 pages), save space by not dumping
any empty residual entries.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 2c55b750a8 ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
Reviewed-by: Alexey Ishchuk <aishchuk@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:13 +01:00
Steffen Maier 569816b4a0 zfcp: fix payload trace length for SAN request&response
commit 94db3725f049ead24c96226df4a4fb375b880a77 upstream.

commit 2c55b750a8
("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
started to add FC_CT_HDR_LEN which made zfcp dump random data
out of bounds for RSPN GS responses because u.rspn.rsp
is the largest and last field in the union of struct zfcp_fc_req.
Other request/response types only happened to stay within bounds
due to the padding of the union or
due to the trace capping of u.gspn.rsp to ZFCP_DBF_SAN_MAX_PAYLOAD.

Timestamp      : ...
Area           : SAN
Subarea        : 00
Level          : 1
Exception      : -
CPU id         : ..
Caller         : ...
Record id      : 2
Tag            : fsscth2
Request id     : 0x...
Destination ID : 0x00fffffc
Payload short  : 01000000 fc020000 80020000 00000000
                 xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx <===
                 00000000 00000000 00000000 00000000
Payload length : 32                                  <===

struct zfcp_fc_req {
    [0] struct zfcp_fsf_ct_els ct_els;
   [56] struct scatterlist sg_req;
   [96] struct scatterlist sg_rsp;
        union {
            struct {req; rsp;} adisc;    SIZE: 28+28=   56
            struct {req; rsp;} gid_pn;   SIZE: 24+20=   44
            struct {rspsg; req;} gpn_ft; SIZE: 40*4+20=180
            struct {req; rsp;} gspn;     SIZE: 20+273= 293
            struct {req; rsp;} rspn;     SIZE: 277+16= 293
  [136] } u;
}
SIZE: 432

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 2c55b750a8 ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
Reviewed-by: Alexey Ishchuk <aishchuk@linux.vnet.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:13 +01:00
Steffen Maier 46737af60b zfcp: fix D_ID field with actual value on tracing SAN responses
commit 771bf03537ddfa4a4dde62ef9dfbc82e4f77ab20 upstream.

With commit 2c55b750a8
("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
we lost the N_Port-ID where an ELS response comes from.
With commit 7c7dc19681
("[SCSI] zfcp: Simplify handling of ct and els requests")
we lost the N_Port-ID where a CT response comes from.
It's especially useful if the request SAN trace record
with D_ID was already lost due to trace buffer wrap.

GS uses an open WKA port handle and ELS just a D_ID, and
only for ELS we could get D_ID from QTCB bottom via zfcp_fsf_req.
To cover both cases, add a new field to zfcp_fsf_ct_els
and fill it in on request to use in SAN response trace.
Strictly speaking the D_ID on SAN response is the FC frame's S_ID.
We don't need a field for the other end which is always us.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 2c55b750a8 ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
Fixes: 7c7dc19681 ("[SCSI] zfcp: Simplify handling of ct and els requests")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:13 +01:00
Steffen Maier 8467dd468c zfcp: restore tracing of handle for port and LUN with HBA records
commit 7c964ffe586bc0c3d9febe9bf97a2e4b2866e5b7 upstream.

This information was lost with
commit a54ca0f62f
("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
but is required to debug e.g. invalid handle situations.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:12 +01:00
Steffen Maier 6916909571 zfcp: trace on request for open and close of WKA port
commit d27a7cb91960cf1fdd11b10071e601828cbf4b1f upstream.

Since commit a54ca0f62f
("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
HBA records no longer contain WWPN, D_ID, or LUN
to reduce duplicate information which is already in REC records.
In contrast to "regular" target ports, we don't use recovery to open
WKA ports such as directory/nameserver, so we don't get REC records.
Therefore, introduce pseudo REC running records without any
actual recovery action but including D_ID of WKA port on open/close.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:12 +01:00
Steffen Maier 053077252d zfcp: restore: Dont use 0 to indicate invalid LUN in rec trace
commit 0102a30a6ff60f4bb4c07358ca3b1f92254a6c25 upstream.

bring back
commit d21e9daa63
("[SCSI] zfcp: Dont use 0 to indicate invalid LUN in rec trace")
which was lost with
commit ae0904f60f
("[SCSI] zfcp: Redesign of the debug tracing for recovery actions.")

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: ae0904f60f ("[SCSI] zfcp: Redesign of the debug tracing for recovery actions.")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:12 +01:00
Steffen Maier 909987d41f zfcp: retain trace level for SCSI and HBA FSF response records
commit 35f040df97fa0e94c7851c054ec71533c88b4b81 upstream.

While retaining the actual filtering according to trace level,
the following commits started to write such filtered records
with a hardcoded record level of 1 instead of the actual record level:
commit 250a1352b9
("[SCSI] zfcp: Redesign of the debug tracing for SCSI records.")
commit a54ca0f62f
("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")

Now we can distinguish written records again for offline level filtering.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 250a1352b9 ("[SCSI] zfcp: Redesign of the debug tracing for SCSI records.")
Fixes: a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:12 +01:00
Steffen Maier efaebcb4ac zfcp: close window with unblocked rport during rport gone
commit 4eeaa4f3f1d6c47b69f70e222297a4df4743363e upstream.

On a successful end of reopen port forced,
zfcp_erp_strategy_followup_success() re-uses the port erp_action
and the subsequent zfcp_erp_action_cleanup() now
sees ZFCP_ERP_SUCCEEDED with
erp_action->action==ZFCP_ERP_ACTION_REOPEN_PORT
instead of ZFCP_ERP_ACTION_REOPEN_PORT_FORCED
but must not perform zfcp_scsi_schedule_rport_register().

We can detect this because the fresh port reopen erp_action
is in its very first step ZFCP_ERP_STEP_UNINITIALIZED.

Otherwise this opens a time window with unblocked rport
(until the followup port reopen recovery would block it again).
If a scsi_cmnd timeout occurs during this time window
fc_timed_out() cannot work as desired and such command
would indeed time out and trigger scsi_eh. This prevents
a clean and timely path failover.
This should not happen if the path issue can be recovered
on FC transport layer such as path issues involving RSCNs.

Also, unnecessary and repeated DID_IMM_RETRY for pending and
undesired new requests occur because internally zfcp still
has its zfcp_port blocked.

As follow-on errors with scsi_eh, it can cause,
in the worst case, permanently lost paths due to one of:
sd <scsidev>: [<scsidisk>] Medium access timeout failure. Offlining disk!
sd <scsidev>: Device offlined - not ready after error recovery

For fix validation and to aid future debugging with other recoveries
we now also trace (un)blocking of rports.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 5767620c38 ("[SCSI] zfcp: Do not unblock rport from REOPEN_PORT_FORCED")
Fixes: a2fa0aede0 ("[SCSI] zfcp: Block FC transport rports early on errors")
Fixes: 5f852be9e1 ("[SCSI] zfcp: Fix deadlock between zfcp ERP and SCSI")
Fixes: 338151e066 ("[SCSI] zfcp: make use of fc_remote_port_delete when target port is unavailable")
Fixes: 3859f6a248 ("[PATCH] zfcp: add rports to enable scsi_add_device to work again")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:12 +01:00
Steffen Maier 5f62704e88 zfcp: fix ELS/GS request&response length for hardware data router
commit 70369f8e15b220f50a16348c79a61d3f7054813c upstream.

In the hardware data router case, introduced with kernel 3.2
commit 86a9668a8d ("[SCSI] zfcp: support for hardware data router")
the ELS/GS request&response length needs to be initialized
as in the chained SBAL case.

Otherwise, the FCP channel rejects ELS requests with
FSF_REQUEST_SIZE_TOO_LARGE.

Such ELS requests can be issued by user space through BSG / HBA API,
or zfcp itself uses ADISC ELS for remote port link test on RSCN.
The latter can cause a short path outage due to
unnecessary remote target port recovery because the always
failing ADISC cannot detect extremely short path interruptions
beyond the local FCP channel.

Below example is decoded with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : SAN
Subarea        : 00
Level          : 1
Exception      : -
CPU id         : ..
Caller         : zfcp_dbf_san_req+0408
Record id      : 1
Tag            : fssels1
Request id     : 0x<reqid>
Destination ID : 0x00<target d_id>
Payload info   : 52000000 00000000 <our wwpn       >           [ADISC]
                 <our wwnn       > 00<s_id> 00000000
                 00000000 00000000 00000000 00000000

Timestamp      : ...
Area           : HBA
Subarea        : 00
Level          : 1
Exception      : -
CPU id         : ..
Caller         : zfcp_dbf_hba_fsf_res+0740
Record id      : 1
Tag            : fs_ferr
Request id     : 0x<reqid>
Request status : 0x00000010
FSF cmnd       : 0x0000000b               [FSF_QTCB_SEND_ELS]
FSF sequence no: 0x...
FSF issued     : ...
FSF stat       : 0x00000061		  [FSF_REQUEST_SIZE_TOO_LARGE]
FSF stat qual  : 00000000 00000000 00000000 00000000
Prot stat      : 0x00000100
Prot stat qual : 00000000 00000000 00000000 00000000

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 86a9668a8d ("[SCSI] zfcp: support for hardware data router")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:11 +01:00
Steffen Maier 6d35bb9a9f zfcp: fix fc_host port_type with NPIV
commit bd77befa5bcff8c51613de271913639edf85fbc2 upstream.

For an NPIV-enabled FCP device, zfcp can erroneously show
"NPort (fabric via point-to-point)" instead of "NPIV VPORT"
for the port_type sysfs attribute of the corresponding
fc_host.
s390-tools that can be affected are dbginfo.sh and ziomon.

zfcp_fsf_exchange_config_evaluate() ignores
fsf_qtcb_bottom_config.connection_features indicating NPIV
and only sets fc_host_port_type to FC_PORTTYPE_NPORT if
fsf_qtcb_bottom_config.fc_topology is FSF_TOPO_FABRIC.

Only the independent zfcp_fsf_exchange_port_evaluate()
evaluates connection_features to overwrite fc_host_port_type
to FC_PORTTYPE_NPIV in case of NPIV.
Code was introduced with upstream kernel 2.6.30
commit 0282985da5
("[SCSI] zfcp: Report fc_host_port_type as NPIV").

This works during FCP device recovery (such as set online)
because it performs FSF_QTCB_EXCHANGE_CONFIG_DATA followed by
FSF_QTCB_EXCHANGE_PORT_DATA in sequence.

However, the zfcp-specific scsi host sysfs attributes
"requests", "megabytes", or "seconds_active" trigger only
zfcp_fsf_exchange_config_evaluate() resetting fc_host
port_type to FC_PORTTYPE_NPORT despite NPIV.

The zfcp-specific scsi host sysfs attribute "utilization"
triggers only zfcp_fsf_exchange_port_evaluate() correcting
the fc_host port_type again in case of NPIV.

Evaluate fsf_qtcb_bottom_config.connection_features
in zfcp_fsf_exchange_config_evaluate() where it belongs to.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 0282985da5 ("[SCSI] zfcp: Report fc_host_port_type as NPIV")
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:33:11 +01:00
Stefan Haberland 2fe6f38f91 s390/dasd: fix hanging device after clear subchannel
commit 9ba333dc55cbb9523553df973adb3024d223e905 upstream.

When a device is in a status where CIO has killed all I/O by itself the
interrupt for a clear request may not contain an irb to determine the
clear function. Instead it contains an error pointer -EIO.
This was ignored by the DASD int_handler leading to a hanging device
waiting for a clear interrupt.

Handle -EIO error pointer correctly for requests that are clear pending and
treat the clear as successful.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-06 23:32:57 +01:00
Ursula Braun 80e90a3123 qeth: delete napi struct when removing a qeth device
commit 7831b4ff0d926e0deeaabef9db8800ed069a2757 upstream.

A qeth_card contains a napi_struct linked to the net_device during
device probing. This struct must be deleted when removing the qeth
device, otherwise Panic on oops can occur when qeth devices are
repeatedly removed and added.

Fixes: a1c3ed4c9c ("qeth: NAPI support for l2 and l3 discipline")
Cc: stable@vger.kernel.org # v2.6.37+
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Tested-by: Alexander Klein <ALKL@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2016-08-27 11:40:32 +02:00
Stefan Haberland 509a4bccfe s390/dasd: fix refcount for PAV reassignment
commit 9d862ababb609439c5d6987f6d3ddd09e703aa0b upstream.

Add refcount to the DASD device when a summary unit check worker is
scheduled. This prevents that the device is set offline with worker
in place.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:06:23 -08:00
Stefan Haberland 9155d3f258 s390/dasd: prevent incorrect length error under z/VM after PAV changes
commit 020bf042e5b397479c1174081b935d0ff15d1a64 upstream.

The channel checks the specified length and the provided amount of
data for CCWs and provides an incorrect length error if the size does
not match. Under z/VM with simulation activated the length may get
changed. Having the suppress length indication bit set is stated as
good CCW coding practice and avoids errors under z/VM.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:06:22 -08:00
Kees Cook e635e0d5b0 crypto: prefix module autoloading with "crypto-"
commit 5d26a105b5a73e5635eae0629b42fa0a90e07b7b upstream.

This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:

https://lkml.org/lkml/2013/3/4/70

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-29 17:40:57 -08:00
Martin Schwidefsky 10baac9160 s390/3215: fix tty output containing tabs
commit e512d56c799517f33b301d81e9a5e0ebf30c2d1e upstream.

git commit 37f81fa1f6
"n_tty: do O_ONLCR translation as a single write"
surfaced a bug in the 3215 device driver. In combination this
broke tab expansion for tty ouput.

The cause is an asymmetry in the behaviour of tty3215_ops->write
vs tty3215_ops->put_char. The put_char function scans for '\t'
but the write function does not.

As the driver has logic for the '\t' expansion remove XTABS
from c_oflag of the initial termios as well.

Reported-by: Stephen Powell <zlinuxman@wowway.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-27 07:52:33 -08:00
Martin Schwidefsky 214a899e44 s390/3215: fix hanging console issue
commit 26d766c60f4ea08cd14f0f3435a6db3d6cc2ae96 upstream.

The ccw_device_start in raw3215_start_io can fail. raw3215_try_io
does not check if the request could be started and removes any
pending timer. This can leave the system in a hanging state.
Check for pending request after raw3215_start_io and start a
timer if necessary.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-27 07:52:33 -08:00
Sebastian Ott 506841af86 s390/chsc: fix SEI usage on old FW levels
commit 06cd7a874ec6e09d151aeb1fa8600e14f1ff89f6 upstream.

Using a notification type mask for the store event information chsc
is unsupported on some firmware levels. Retry SEI with that mask set
to zero (which is the old way of requesting only channel subsystem
related events).

Reported-and-tested-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-13 13:59:42 +02:00
Sebastian Ott 6a52b43b32 s390/cio: fix driver callback initialization for ccw consoles
commit 2253e8d79237c69086ded391e6767afe16972527 upstream.

ccw consoles are in use before they can be properly registered with
the driver core. For devices which are in use by a device driver we
rely on the ccw_device's pointer to the driver callbacks to be valid.
For ccw consoles this pointer is NULL until they are registered later
during boot and we dereferenced this pointer. This worked by
chance on 64 bit builds (cdev->drv was NULL but the optional callback
cdev->drv->path_event was also NULL by coincidence) and was unnoticed
until we received reports about boot failures on 31 bit systems.
Fix it by initializing the driver pointer for ccw consoles.

Reported-by: Mike Frysinger <vapier@gentoo.org>
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-06 07:55:27 -07:00
Heiko Carstens ed93fb01a3 s390/dasd: hold request queue sysfs lock when calling elevator_init()
commit ef0899410ff630b2e75306da49996dbbfa318165 upstream.

"elevator: Fix a race in elevator switching and md device initialization"
changed the semantics of elevator_init() in a way that now enforces to hold
the corresponding request queue's sysfs_lock when calling elevator_init()
to fix a race.
The patch did not convert the s390 dasd device driver which is the only
device driver which also calls elevator_init(). So add the missing locking.

Cc: Tomoki Sekiyama <tomoki.sekiyama@hds.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Cc: Christian Borntraeger <christian@borntraeger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-23 21:38:20 -07:00
Martin Schwidefsky 2202b3646c s390/3270: fix allocation of tty3270_screen structure
commit 36d9f4d3b68c7035ead3850dc85f310a579ed0eb upstream.

The tty3270_alloc_screen function is called from tty3270_install with
swapped arguments, the number of columns instead of rows and vice versa.
The number of rows is typically smaller than the number of columns which
makes the screen array too big but the individual cell arrays for the
lines too small. Creating lines longer than the number of rows will
clobber the memory after the end of the cell array.
The fix is simple, call tty3270_alloc_screen with the correct argument
order.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-09 12:24:24 -08:00
Ursula Braun 9dc2f26742 qeth: avoid buffer overflow in snmp ioctl
commit 6fb392b1a63ae36c31f62bc3fc8630b49d602b62 upstream.

Check user-defined length in snmp ioctl request and allow request
only if it fits into a qeth command buffer.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Reviewed-by: Heiko Carstens <heicars2@linux.vnet.ibm.com>
Reported-by: Nico Golde <nico@ngolde.de>
Reported-by: Fabian Yamaguchi <fabs@goesec.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-04 10:56:37 -08:00
Martin Peschke e1a289ee67 SCSI: zfcp: fix schedule-inside-lock in scsi_device list loops
commit 924dd584b198a58aa7cb3efefd8a03326550ce8f upstream.

BUG: sleeping function called from invalid context at kernel/workqueue.c:2752
in_atomic(): 1, irqs_disabled(): 1, pid: 360, name: zfcperp0.0.1700
CPU: 1 Not tainted 3.9.3+ #69
Process zfcperp0.0.1700 (pid: 360, task: 0000000075b7e080, ksp: 000000007476bc30)
<snip>
Call Trace:
([<00000000001165de>] show_trace+0x106/0x154)
 [<00000000001166a0>] show_stack+0x74/0xf4
 [<00000000006ff646>] dump_stack+0xc6/0xd4
 [<000000000017f3a0>] __might_sleep+0x128/0x148
 [<000000000015ece8>] flush_work+0x54/0x1f8
 [<00000000001630de>] __cancel_work_timer+0xc6/0x128
 [<00000000005067ac>] scsi_device_dev_release_usercontext+0x164/0x23c
 [<0000000000161816>] execute_in_process_context+0x96/0xa8
 [<00000000004d33d8>] device_release+0x60/0xc0
 [<000000000048af48>] kobject_release+0xa8/0x1c4
 [<00000000004f4bf2>] __scsi_iterate_devices+0xfa/0x130
 [<000003ff801b307a>] zfcp_erp_strategy+0x4da/0x1014 [zfcp]
 [<000003ff801b3caa>] zfcp_erp_thread+0xf6/0x2b0 [zfcp]
 [<000000000016b75a>] kthread+0xf2/0xfc
 [<000000000070c9de>] kernel_thread_starter+0x6/0xc
 [<000000000070c9d8>] kernel_thread_starter+0x0/0xc

Apparently, the ref_count for some scsi_device drops down to zero,
triggering device removal through execute_in_process_context(), while
the lldd error recovery thread iterates through a scsi device list.
Unfortunately, execute_in_process_context() decides to immediately
execute that device removal function, instead of scheduling asynchronous
execution, since it detects process context and thinks it is safe to do
so. But almost all calls to shost_for_each_device() in our lldd are
inside spin_lock_irq, even in thread context. Obviously, schedule()
inside spin_lock_irq sections is a bad idea.

Change the lldd to use the proper iterator function,
__shost_for_each_device(), in combination with required locking.

Occurences that need to be changed include all calls in zfcp_erp.c,
since those might be executed in zfcp error recovery thread context
with a lock held.

Other occurences of shost_for_each_device() in zfcp_fsf.c do not
need to be changed (no process context, no surrounding locking).

The problem was introduced in Linux 2.6.37 by commit
b62a8d9b45
"[SCSI] zfcp: Use SCSI device data zfcp_scsi_dev instead of zfcp_unit".

Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-29 09:47:39 -07:00
Martin Peschke bda5d1efa0 SCSI: zfcp: fix lock imbalance by reworking request queue locking
commit d79ff142624e1be080ad8d09101f7004d79c36e1 upstream.

This patch adds wait_event_interruptible_lock_irq_timeout(), which is a
straight-forward descendant of wait_event_interruptible_timeout() and
wait_event_interruptible_lock_irq().

The zfcp driver used to call wait_event_interruptible_timeout()
in combination with some intricate and error-prone locking. Using
wait_event_interruptible_lock_irq_timeout() as a replacement
nicely cleans up that locking.

This rework removes a situation that resulted in a locking imbalance
in zfcp_qdio_sbal_get():

BUG: workqueue leaked lock or atomic: events/1/0xffffff00/10
    last function: zfcp_fc_wka_port_offline+0x0/0xa0 [zfcp]

It was introduced by commit c2af7545aa
"[SCSI] zfcp: Do not wait for SBALs on stopped queue", which had a new
code path related to ZFCP_STATUS_ADAPTER_QDIOUP that took an early exit
without a required lock being held. The problem occured when a
special, non-SCSI I/O request was being submitted in process context,
when the adapter's queues had been torn down. In this case the bug
surfaced when the Fibre Channel port connection for a well-known address
was closed during a concurrent adapter shut-down procedure, which is a
rare constellation.

This patch also fixes these warnings from the sparse tool (make C=1):

drivers/s390/scsi/zfcp_qdio.c:224:12: warning: context imbalance in
 'zfcp_qdio_sbal_check' - wrong count at exit
drivers/s390/scsi/zfcp_qdio.c:244:5: warning: context imbalance in
 'zfcp_qdio_sbal_get' - unexpected unlock

Last but not least, we get rid of that crappy lock-unlock-lock
sequence at the beginning of the critical section.

It is okay to call zfcp_erp_adapter_reopen() with req_q_lock held.

Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-29 09:47:39 -07:00
Steffen Maier 8f425c63ec SCSI: zfcp: status read buffers on first adapter open with link down
commit 9edf7d75ee5f21663a0183d21f702682d0ef132f upstream.

Commit 64deb6efdc
"[SCSI] zfcp: Use status_read_buf_num provided by FCP channel"
started using a value returned by the channel but only evaluated the value
if the fabric link is up.
Commit 8d88cf3f3b
"[SCSI] zfcp: Update status read mempool"
introduced mempool resizings based on the above value.
On setting an FCP device online for the very first time since boot, a new
zeroed adapter object is allocated. If the link is down, the number of
status read requests remains zero. Since just the config data exchange is
incomplete, we proceed with adapter open recovery. However, we
unconditionally call mempool_resize with adapter->stat_read_buf_num == 0 in
this case.

This causes a kernel message "kernel BUG at mm/mempool.c:131!" in process
"zfcperp<FCP-device-bus-ID>" with last function mempool_resize in Krnl PSW
and zfcp_erp_thread in the Call Trace.

Don't evaluate channel values which are invalid on link down. The number of
status read requests is always valid, evaluated, and set to a positive
minimum greater than zero. The adapter open recovery can proceed and the
channel has status read buffers to inform us on a future link up event.
While we are not aware of any other code path that could result in mempool
resize attempts of size zero, we still also initialize the number of status
read buffers to be posted to a static minimum number on adapter object
allocation.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25 14:07:30 -07:00
Steffen Maier b22b838699 SCSI: zfcp: block queue limits with data router
commit 5fea4291deacd80188b996d2f555fc6a1940e5d4 upstream.

Commit 86a9668a8d
"[SCSI] zfcp: support for hardware data router"
reduced the initial block queue limits in the scsi_host_template to the
absolute minimum and adjusted them later on. However, the adjustment was
too late for the BSG devices of Scsi_Host and fc_host.

Therefore, ioctl(..., SG_IO, ...) with request or response size > 4kB to a
BSG device of an fc_host or a Scsi_Host fails with EINVAL. As a result,
users of such ioctl such as HBA_SendCTPassThru() in libzfcphbaapi return
with error HBA_STATUS_ERROR.

Initialize the block queue limits in zfcp_scsi_host_template to the
greatest common denominator (GCD).

While we cannot exploit the slightly enlarged maximum request size with
data router, this should be neglectible. Doing so also avoids running into
trouble after live guest relocation (LGR) / migration from a data router
FCP device to an FCP device that does not support data router. In that
case, zfcp would figure out the new limits on adapter recovery, but the
fc_host and Scsi_Host (plus in fact all sdevs) still exist with the old and
now too large queue limits.

It should also OK, not to use half the size as in the DIX case, because
fc_host and Scsi_Host do not transport FCP requests including SCSI commands
using protection data.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25 14:07:30 -07:00
Daniel Hansel 88bc592804 SCSI: zfcp: fix adapter (re)open recovery while link to SAN is down
commit f76ccaac4f82c463a037aa4a1e4ccb85c7011814 upstream.

FCP device remains in status ERP_FAILED when device is switched online
or adapter recovery is triggered  while link to SAN is down.

When Exchange Configuration Data command returns the FSF status
FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE it aborts the exchange process.
The only retries are done during the common error recovery procedure
(i.e. max. 3 retries with 8sec sleep between) and remains in status
ERP_FAILED with QDIO down.

This commit reverts the commit 0df138476c
(zfcp: Fix adapter activation on link down).
When FSF status FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE is received the
adapter recovery will be finished without any retries. QDIO will be
up now and status changes such as LINK UP will be received now.

Signed-off-by: Daniel Hansel <daniel.hansel@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25 14:07:30 -07:00
Benjamin Poirier aaf9522d62 netiucv: Hold rtnl between name allocation and device registration.
fixes a race condition between concurrent initializations of netiucv devices
that try to use the same name.

sysfs: cannot create duplicate filename '/devices/iucv/netiucv2'
[...]
Call Trace:
([<00000000002edea4>] sysfs_add_one+0xb0/0xdc)
 [<00000000002eecd4>] create_dir+0x80/0xfc
 [<00000000002eee38>] sysfs_create_dir+0xe8/0x118
 [<00000000003835a8>] kobject_add_internal+0x120/0x2d0
 [<00000000003839d6>] kobject_add+0x62/0x9c
 [<00000000003d9564>] device_add+0xcc/0x510
 [<000003e00212c7b4>] netiucv_register_device+0xc0/0x1ec [netiucv]

Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
Tested-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-13 17:41:18 -07:00
Stefan Weinhuber 8b811bae69 s390/dasd: fix handling of gone paths
When a path is gone and dasd_generic_path_event is called with a
PE_PATH_GONE event, we must assume that any I/O request on that
subchannel is still running. This is unlike the dasd_generic_notify
handler and the CIO_NO_PATH event, which implies that the subchannel
has been cleared.
If dasd_generic_path_event finds that the path has been the last
usable path, it must not call dasd_generic_last_path_gone (which would
reset the state of running requests), but just set the
DASD_STOPPED_DC_WAIT bit.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-05-31 17:23:49 +02:00
Linus Torvalds c4ad180f0e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 update from Martin Schwidefsky:
 "An additional sysfs attribute for channel paths and a couple of bux
  fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/pgtable: fix ipte notify bit
  s390/xpram: mark xpram as non-rotational
  s390/smp: fix cpu re-scan vs. cpu state
  s390/cio: add channel ID sysfs attribute
  s390/ftrace: fix mcount adjustment
  s390: fix gmap_ipte_notifier vs. software dirty pages
  s390: disable pfmf for clear page instruction
  s390/disassembler: prevent endless loop in print_fn_code()
  s390: remove non existent reference to GENERIC_KERNEL_THREAD
2013-05-21 09:36:46 -07:00
Christian Borntraeger 00e5d35c0f s390/xpram: mark xpram as non-rotational
xpram is a memory technology. Lets mark that as non-rotational.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-05-17 11:47:04 +02:00
Peter Oberparleiter ba54229db6 s390/cio: add channel ID sysfs attribute
Add new attributes "chid" and "chid_external" to the channel-path
sysfs directory. These attributes contain information related to
the channel-ID of the channel-path.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-05-15 16:47:39 +02:00
Linus Torvalds 4de13d7aa8 Merge branch 'for-3.10/core' of git://git.kernel.dk/linux-block
Pull block core updates from Jens Axboe:

 - Major bit is Kents prep work for immutable bio vecs.

 - Stable candidate fix for a scheduling-while-atomic in the queue
   bypass operation.

 - Fix for the hang on exceeded rq->datalen 32-bit unsigned when merging
   discard bios.

 - Tejuns changes to convert the writeback thread pool to the generic
   workqueue mechanism.

 - Runtime PM framework, SCSI patches exists on top of these in James'
   tree.

 - A few random fixes.

* 'for-3.10/core' of git://git.kernel.dk/linux-block: (40 commits)
  relay: move remove_buf_file inside relay_close_buf
  partitions/efi.c: replace useless kzalloc's by kmalloc's
  fs/block_dev.c: fix iov_shorten() criteria in blkdev_aio_read()
  block: fix max discard sectors limit
  blkcg: fix "scheduling while atomic" in blk_queue_bypass_start
  Documentation: cfq-iosched: update documentation help for cfq tunables
  writeback: expose the bdi_wq workqueue
  writeback: replace custom worker pool implementation with unbound workqueue
  writeback: remove unused bdi_pending_list
  aoe: Fix unitialized var usage
  bio-integrity: Add explicit field for owner of bip_buf
  block: Add an explicit bio flag for bios that own their bvec
  block: Add bio_alloc_pages()
  block: Convert some code to bio_for_each_segment_all()
  block: Add bio_for_each_segment_all()
  bounce: Refactor __blk_queue_bounce to not use bi_io_vec
  raid1: use bio_copy_data()
  pktcdvd: Use bio_reset() in disabled code to kill bi_idx usage
  pktcdvd: use bio_copy_data()
  block: Add bio_copy_data()
  ...
2013-05-08 10:13:35 -07:00
Linus Torvalds 292088ee03 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "A couple of fixes + getting rid of __blkdev_put() return value"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  proc: Use PDE attribute setting accessor functions
  make blkdev_put() return void
  block_device_operations->release() should return void
  mtd_blktrans_ops->release() should return void
  hfs: SMP race on directory close()
2013-05-07 15:14:53 -07:00
Al Viro db2a144bed block_device_operations->release() should return void
The value passed is 0 in all but "it can never happen" cases (and those
only in a couple of drivers) *and* it would've been lost on the way
out anyway, even if something tried to pass something meaningful.
Just don't bother.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-07 02:16:21 -04:00
Linus Torvalds 2bf1bef0d6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull more s390 updates from Martin Schwidefsky:
 "This is the second batch of s390 patches for the 3.10 merge window.

  Heiko improved the memory detection, this fixes kdump for large memory
  sizes.  Some kvm related memory management work, new ipldev/condev
  keywords in cio and bug fixes."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/mem_detect: remove artificial kdump memory types
  s390/mm: add pte invalidation notifier for kvm
  s390/zcrypt: ap bus rescan problem when toggle crypto adapters on/off
  s390/memory hotplug,sclp: get rid of per memory increment usecount
  s390/memory hotplug: provide memory_block_size_bytes() function
  s390/mem_detect: limit memory detection loop to "mem=" parameter
  s390/kdump,bootmem: fix bootmem allocator bitmap size
  s390: get rid of odd global real_memory_size
  s390/kvm: Change the virtual memory mapping location for Virtio devices
  s390/zcore: calculate real memory size using own get_mem_size function
  s390/mem_detect: add DAT sanity check
  s390/mem_detect: fix lockdep irq tracing
  s390/mem_detect: move memory detection code to mm folder
  s390/zfcpdump: exploit new cio_ignore keywords
  s390/cio: add condev keyword to cio_ignore
  s390/cio: add ipldev keyword to cio_ignore
  s390/uaccess: add "fallthrough" comments
2013-05-06 12:34:53 -07:00
Linus Torvalds 01227a889e Merge tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Gleb Natapov:
 "Highlights of the updates are:

  general:
   - new emulated device API
   - legacy device assignment is now optional
   - irqfd interface is more generic and can be shared between arches

  x86:
   - VMCS shadow support and other nested VMX improvements
   - APIC virtualization and Posted Interrupt hardware support
   - Optimize mmio spte zapping

  ppc:
    - BookE: in-kernel MPIC emulation with irqfd support
    - Book3S: in-kernel XICS emulation (incomplete)
    - Book3S: HV: migration fixes
    - BookE: more debug support preparation
    - BookE: e6500 support

  ARM:
   - reworking of Hyp idmaps

  s390:
   - ioeventfd for virtio-ccw

  And many other bug fixes, cleanups and improvements"

* tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
  kvm: Add compat_ioctl for device control API
  KVM: x86: Account for failing enable_irq_window for NMI window request
  KVM: PPC: Book3S: Add API for in-kernel XICS emulation
  kvm/ppc/mpic: fix missing unlock in set_base_addr()
  kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write
  kvm/ppc/mpic: remove users
  kvm/ppc/mpic: fix mmio region lists when multiple guests used
  kvm/ppc/mpic: remove default routes from documentation
  kvm: KVM_CAP_IOMMU only available with device assignment
  ARM: KVM: iterate over all CPUs for CPU compatibility check
  KVM: ARM: Fix spelling in error message
  ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally
  KVM: ARM: Fix API documentation for ONE_REG encoding
  ARM: KVM: promote vfp_host pointer to generic host cpu context
  ARM: KVM: add architecture specific hook for capabilities
  ARM: KVM: perform HYP initilization for hotplugged CPUs
  ARM: KVM: switch to a dual-step HYP init code
  ARM: KVM: rework HYP page table freeing
  ARM: KVM: enforce maximum size for identity mapped code
  ARM: KVM: move to a KVM provided HYP idmap
  ...
2013-05-05 14:47:31 -07:00
Ingo Tuchscherer 56bbe68669 s390/zcrypt: ap bus rescan problem when toggle crypto adapters on/off
The bus rescan process was called simultaneously on
every device failure. This finally leads into race
conditions (double device add/remove actions).

This patch protects the rescan area by mutual exclusion
and improves ap_config_timer handling

Signed-off-by: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-05-02 17:10:20 +02:00