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2018-07-03scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handlerSteffen Maier
commit df30781699f53e4fd4c494c6f7dd16e3d5c21d30 upstream. For problem determination we need to see whether and why we were successful or not. This allows deduction of scsi_eh escalation. Example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : schrh_r SCSI host reset handler result Request ID : 0x0000000000000000 none (invalid) SCSI ID : 0xffffffff none (invalid) SCSI LUN : 0xffffffff none (invalid) SCSI LUN high : 0xffffffff none (invalid) SCSI result : 0x00002002 field re-used for midlayer value: SUCCESS or in other cases: 0x2009 == FAST_IO_FAIL SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0xff none (invalid) FCP rsp IU : 00000000 00000000 00000000 00000000 none (invalid) 00000000 00000000 v2.6.35 commit a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") introduced the first return with something other than the previously hardcoded single SUCCESS return path. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Fixes: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") Cc: <stable@vger.kernel.org> #2.6.38+ 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>
2018-05-30s390/cio: clear timer when terminating driver I/OSebastian Ott
[ Upstream commit 410d5e13e7638bc146321671e223d56495fbf3c7 ] When we terminate driver I/O (because we need to stop using a certain channel path) we also need to ensure that a timer (which may have been set up using ccw_device_start_timeout) is cleared. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30s390/cio: fix return code after missing interruptSebastian Ott
[ Upstream commit 770b55c995d171f026a9efb85e71e3b1ea47b93d ] When a timeout occurs for users of ccw_device_start_timeout we will stop the IO and call the drivers int handler with the irb pointer set to ERR_PTR(-ETIMEDOUT). Sometimes however we'd set the irb pointer to ERR_PTR(-EIO) which is not intended. Just set the correct value in all codepaths. Reported-by: Julian Wiedmann <jwi@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: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26scsi: zfcp: fix infinite iteration on ERP ready listJens Remus
commit fa89adba1941e4f3b213399b81732a5c12fd9131 upstream. zfcp_erp_adapter_reopen() schedules blocking of all of the adapter's rports via zfcp_scsi_schedule_rports_block() and enqueues a reopen adapter ERP action via zfcp_erp_action_enqueue(). Both are separately processed asynchronously and concurrently. Blocking of rports is done in a kworker by zfcp_scsi_rport_work(). It calls zfcp_scsi_rport_block(), which then traces a DBF REC "scpdely" via zfcp_dbf_rec_trig(). zfcp_dbf_rec_trig() acquires the DBF REC spin lock and then iterates with list_for_each() over the adapter's ERP ready list without holding the ERP lock. This opens a race window in which the current list entry can be moved to another list, causing list_for_each() to iterate forever on the wrong list, as the erp_ready_head is never encountered as terminal condition. Meanwhile the ERP action can be processed in the ERP thread by zfcp_erp_thread(). It calls zfcp_erp_strategy(), which acquires the ERP lock and then calls zfcp_erp_action_to_running() to move the ERP action from the ready to the running list. zfcp_erp_action_to_running() can move the ERP action using list_move() just during the aforementioned race window. It then traces a REC RUN "erator1" via zfcp_dbf_rec_run(). zfcp_dbf_rec_run() tries to acquire the DBF REC spin lock. If this is held by the infinitely looping kworker, it effectively spins forever. Example Sequence Diagram: Process ERP Thread rport_work ------------------- ------------------- ------------------- zfcp_erp_adapter_reopen() zfcp_erp_adapter_block() zfcp_scsi_schedule_rports_block() lock ERP zfcp_scsi_rport_work() zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER) list_add_tail() on ready !(rport_task==RPORT_ADD) wake_up() ERP thread zfcp_scsi_rport_block() zfcp_dbf_rec_trig() zfcp_erp_strategy() zfcp_dbf_rec_trig() unlock ERP lock DBF REC zfcp_erp_wait() lock ERP | zfcp_erp_action_to_running() | list_for_each() ready | list_move() current entry | ready to running | zfcp_dbf_rec_run() endless loop over running | zfcp_dbf_rec_run_lvl() | lock DBF REC spins forever Any adapter recovery can trigger this, such as setting the device offline or reboot. V4.9 commit 4eeaa4f3f1d6 ("zfcp: close window with unblocked rport during rport gone") introduced additional tracing of (un)blocking of rports. It missed that the adapter->erp_lock must be held when calling zfcp_dbf_rec_trig(). This fix uses the approach formerly introduced by commit aa0fec62391c ("[SCSI] zfcp: Fix sparse warning by providing new entry in dbf") that got later removed by commit ae0904f60fab ("[SCSI] zfcp: Redesign of the debug tracing for recovery actions."). Introduce zfcp_dbf_rec_trig_lock(), a wrapper for zfcp_dbf_rec_trig() that acquires and releases the adapter->erp_lock for read. Reported-by: Sebastian Ott <sebott@linux.ibm.com> Signed-off-by: Jens Remus <jremus@linux.ibm.com> Fixes: 4eeaa4f3f1d6 ("zfcp: close window with unblocked rport during rport gone") Cc: <stable@vger.kernel.org> # 2.6.32+ Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Steffen Maier <maier@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26s390/qdio: don't release memory in qdio_setup_irq()Julian Wiedmann
commit 2e68adcd2fb21b7188ba449f0fab3bee2910e500 upstream. Calling qdio_release_memory() on error is just plain wrong. It frees the main qdio_irq struct, when following code still uses it. Also, no other error path in qdio_establish() does this. So trust callers to clean up via qdio_free() if some step of the QDIO initialization fails. Fixes: 779e6e1c724d ("[S390] qdio: new qdio driver.") Cc: <stable@vger.kernel.org> #v2.6.27+ Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26s390/qdio: fix access to uninitialized qdio_q fieldsJulian Wiedmann
commit e521813468f786271a87e78e8644243bead48fad upstream. Ever since CQ/QAOB support was added, calling qdio_free() straight after qdio_alloc() results in qdio_release_memory() accessing uninitialized memory (ie. q->u.out.use_cq and q->u.out.aobs). Followed by a kmem_cache_free() on the random AOB addresses. For older kernels that don't have 6e30c549f6ca, the same applies if qdio_establish() fails in the DEV_STATE_ONLINE check. While initializing q->u.out.use_cq would be enough to fix this particular bug, the more future-proof change is to just zero-alloc the whole struct. Fixes: 104ea556ee7f ("qdio: support asynchronous delivery of storage blocks") Cc: <stable@vger.kernel.org> #v3.2+ Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-29s390/cio: update chpid descriptor after resource accessibility eventSebastian Ott
commit af2e460ade0b0180d0f3812ca4f4f59cc9597f3e upstream. Channel path descriptors have been seen as something stable (as long as the chpid is configured). Recent tests have shown that the descriptor can also be altered when the link state of a channel path changes. Thus it is necessary to update the descriptor during handling of resource accessibility events. Cc: <stable@vger.kernel.org> Signed-off-by: Sebastian Ott <sebott@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-29s390: introduce execute-trampolines for branchesMartin Schwidefsky
[ Upstream commit f19fbd5ed642dc31c809596412dab1ed56f2f156 ] Add CONFIG_EXPOLINE to enable the use of the new -mindirect-branch= and -mfunction_return= compiler options to create a kernel fortified against the specte v2 attack. With CONFIG_EXPOLINE=y all indirect branches will be issued with an execute type instruction. For z10 or newer the EXRL instruction will be used, for older machines the EX instruction. The typical indirect call basr %r14,%r1 is replaced with a PC relative call to a new thunk brasl %r14,__s390x_indirect_jump_r1 The thunk contains the EXRL/EX instruction to the indirect branch __s390x_indirect_jump_r1: exrl 0,0f j . 0: br %r1 The detour via the execute type instruction has a performance impact. To get rid of the detour the new kernel parameter "nospectre_v2" and "spectre_v2=[on,off,auto]" can be used. If the parameter is specified the kernel and module code will be patched at runtime. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-24s390/qdio: don't merge ERROR output buffersJulian Wiedmann
commit 0cf1e05157b9e5530dcc3ca9fec9bf617fc93375 upstream. On an Output queue, both EMPTY and PENDING buffer states imply that the buffer is ready for completion-processing by the upper-layer drivers. So for a non-QEBSM Output queue, get_buf_states() merges mixed batches of PENDING and EMPTY buffers into one large batch of EMPTY buffers. The upper-layer driver (ie. qeth) later distuingishes PENDING from EMPTY by inspecting the slsb_state for QDIO_OUTBUF_STATE_FLAG_PENDING. But the merge logic in get_buf_states() contains a bug that causes us to erronously also merge ERROR buffers into such a batch of EMPTY buffers (ERROR is 0xaf, EMPTY is 0xa1; so ERROR & EMPTY == EMPTY). Effectively, most outbound ERROR buffers are currently discarded silently and processed as if they had succeeded. Note that this affects _all_ non-QEBSM device types, not just IQD with CQ. Fix it by explicitly spelling out the exact conditions for merging. For extracting the "get initial state" part out of the loop, this relies on the fact that get_buf_states() is never called with a count of 0. The QEBSM path already strictly requires this, and the two callers with variable 'count' make sure of it. Fixes: 104ea556ee7f ("qdio: support asynchronous delivery of storage blocks") Cc: <stable@vger.kernel.org> #v3.2+ Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-24s390/qdio: don't retry EQBS after CCQ 96Julian Wiedmann
commit dae55b6fef58530c13df074bcc182c096609339e upstream. Immediate retry of EQBS after CCQ 96 means that we potentially misreport the state of buffers inspected during the first EQBS call. This occurs when 1. the first EQBS finds all inspected buffers still in the initial state set by the driver (ie INPUT EMPTY or OUTPUT PRIMED), 2. the EQBS terminates early with CCQ 96, and 3. by the time that the second EQBS comes around, the state of those previously inspected buffers has changed. If the state reported by the second EQBS is 'driver-owned', all we know is that the previous buffers are driver-owned now as well. But we can't tell if they all have the same state. So for instance - the second EQBS reports OUTPUT EMPTY, but any number of the previous buffers could be OUTPUT ERROR by now, - the second EQBS reports OUTPUT ERROR, but any number of the previous buffers could be OUTPUT EMPTY by now. Effectively, this can result in both over- and underreporting of errors. If the state reported by the second EQBS is 'HW-owned', that doesn't guarantee that the previous buffers have not been switched to driver-owned in the mean time. So for instance - the second EQBS reports INPUT EMPTY, but any number of the previous buffers could be INPUT PRIMED (or INPUT ERROR) by now. This would result in failure to process pending work on the queue. If it's the final check before yielding initiative, this can cause a (temporary) queue stall due to IRQ avoidance. Fixes: 25f269f17316 ("[S390] qdio: EQBS retry after CCQ 96") Cc: <stable@vger.kernel.org> #v3.2+ Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13s390/dasd: fix hanging safe offlineStefan Haberland
[ Upstream commit e8ac01555d9e464249e8bb122337d6d6e5589ccc ] The safe offline processing may hang forever because it waits for I/O which can not be started because of the offline flag that prevents new I/O from being started. Allow I/O to be started during safe offline processing because in this special case we take care that the queues are empty before throwing away the device. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-31s390/qeth: on channel error, reject further cmd requestsJulian Wiedmann
[ Upstream commit a6c3d93963e4b333c764fde69802c3ea9eaa9d5c ] When the IRQ handler determines that one of the cmd IO channels has failed and schedules recovery, block any further cmd requests from being submitted. The request would inevitably stall, and prevent the recovery from making progress until the request times out. This sort of error was observed after Live Guest Relocation, where the pending IO on the READ channel intentionally gets terminated to kick-start recovery. Simultaneously the guest executed SIOCETHTOOL, triggering qeth to issue a QUERY CARD INFO command. The command then stalled in the inoperabel WRITE channel. Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-31s390/qeth: lock read device while queueing next bufferJulian Wiedmann
[ Upstream commit 17bf8c9b3d499d5168537c98b61eb7a1fcbca6c2 ] For calling ccw_device_start(), issue_next_read() needs to hold the device's ccwlock. This is satisfied for the IRQ handler path (where qeth_irq() gets called under the ccwlock), but we need explicit locking for the initial call by the MPC initialization. Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-31s390/qeth: when thread completes, wake up all waitersJulian Wiedmann
[ Upstream commit 1063e432bb45be209427ed3f1ca3908e4aa3c7d7 ] qeth_wait_for_threads() is potentially called by multiple users, make sure to notify all of them after qeth_clear_thread_running_bit() adjusted the thread_running_mask. With no timeout, callers would otherwise stall. Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-31s390/qeth: free netdevice when removing a cardJulian Wiedmann
[ Upstream commit 6be687395b3124f002a653c1a50b3260222b3cd7 ] On removal, a qeth card's netdevice is currently not properly freed because the call chain looks as follows: qeth_core_remove_device(card) lx_remove_device(card) unregister_netdev(card->dev) card->dev = NULL !!! qeth_core_free_card(card) if (card->dev) !!! free_netdev(card->dev) Fix it by free'ing the netdev straight after unregistering. This also fixes the sysfs-driven layer switch case (qeth_dev_layer2_store()), where the need to free the current netdevice was not considered at all. Note that free_netdev() takes care of the netif_napi_del() for us too. Fixes: 4a71df50047f ("qeth: new qeth device driver") Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-11s390/qeth: fix IPA command submission raceJulian Wiedmann
[ Upstream commit d22ffb5a712f9211ffd104c38fc17cbfb1b5e2b0 ] If multiple IPA commands are build & sent out concurrently, fill_ipacmd_header() may assign a seqno value to a command that's different from what send_control_data() later assigns to this command's reply. This is due to other commands passing through send_control_data(), and incrementing card->seqno.ipa along the way. So one IPA command has no reply that's waiting for its seqno, while some other IPA command has multiple reply objects waiting for it. Only one of those waiting replies wins, and the other(s) times out and triggers a recovery via send_ipa_cmd(). Fix this by making sure that the same seqno value is assigned to a command and its reply object. Do so immediately before submitting the command & while holding the irq_pending "lock", to produce nicely ascending seqnos. As a side effect, *all* IPA commands now use a reply object that's waiting for its actual seqno. Previously, early IPA commands that were submitted while the card was still DOWN used the "catch-all" IDX seqno. Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-11s390/qeth: fix SETIP command handlingJulian Wiedmann
[ Upstream commit 1c5b2216fbb973a9410e0b06389740b5c1289171 ] send_control_data() applies some special handling to SETIP v4 IPA commands. But current code parses *all* command types for the SETIP command code. Limit the command code check to IPA commands. Fixes: 5b54e16f1a54 ("qeth: do not spin for SETIP ip assist command") Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-03s390/dasd: fix wrongly assigned configuration dataStefan Haberland
[ Upstream commit 8a9bd4f8ebc6800bfc0596e28631ff6809a2f615 ] We store per path and per device configuration data to identify the path or device correctly. The per path configuration data might get mixed up if the original request gets into error recovery and is started with a random path mask. This would lead to a wrong identification of a path in case of a CUIR event for example. Fix by copying the path mask from the original request to the error recovery request in case it is a path verification request. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Reviewed-by: Jan Hoeppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25s390/dasd: prevent prefix I/O errorStefan Haberland
[ Upstream commit da340f921d3454f1521671c7a5a43ad3331fbe50 ] Prevent that a prefix flag is set based on invalid configuration data. The validity.verify_base flag should only be set for alias devices. Usually the unit address type is either one of base, PAV alias or HyperPAV alias. But in cases where the unit address type is not set or any other value the validity.verify_base flag might be set as well. This would lead to follow on errors. Explicitly check for alias devices and set the validity flag only for them. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Reviewed-by: Jan Hoeppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-25s390/qeth: no ETH header for outbound AF_IUCVJulian Wiedmann
[ Upstream commit acd9776b5c45ef02d1a210969a6fcc058afb76e3 ] With AF_IUCV traffic, the skb passed to hard_start_xmit() has a 14 byte slot at skb->data, intended for an ETH header. qeth_l3_fill_af_iucv_hdr() fills this ETH header... and then immediately moves it to the skb's headroom, where it disappears and is never seen again. But it's still possible for us to return NETDEV_TX_BUSY after the skb has been modified. Since we didn't get a private copy of the skb, the next time the skb is delivered to hard_start_xmit() it no longer has the expected layout (we moved the ETH header to the headroom, so skb->data now starts at the IUCV_TRANS header). So when qeth_l3_fill_af_iucv_hdr() does another round of rebuilding, the resulting qeth header ends up all wrong. On transmission, the buffer is then rejected by the HiperSockets device with SBALF15 = x'04'. When this error is passed back to af_iucv as TX_NOTIFY_UNREACHABLE, it tears down the offending socket. As the ETH header for AF_IUCV serves no purpose, just align the code to what we do for IP traffic on L3 HiperSockets: keep the ETH header at skb->data, and pass down data_offset = ETH_HLEN to qeth_fill_buffer(). When mapping the payload into the SBAL elements, the ETH header is then stripped off. This avoids the skb manipulations in qeth_l3_fill_af_iucv_hdr(), and any buffer re-entering hard_start_xmit() after NETDEV_TX_BUSY is now processed properly. Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-15s390/qeth: issue STARTLAN as first IPA commandJulian Wiedmann
[ Upstream commit 1034051045d125579ab1e8fcd5a724eeb0e70149 ] STARTLAN needs to be the first IPA command after MPC initialization completes. So move the qeth_send_startlan() call from the layer disciplines into the core path, right after the MPC handshake. While at it, replace the magic LAN OFFLINE return code with the existing enum. Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com> Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08s390/dasd: check for device error pointer within state change interruptsStefan Haberland
[ Upstream commit 2202134e48a3b50320aeb9e3dd1186833e9d7e66 ] Check if the device pointer is valid. Just a sanity check since we already are in the int handler of the device. Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02scsi: zfcp: fix erp_action use-before-initialize in REC action traceSteffen Maier
commit ab31fd0ce65ec93828b617123792c1bb7c6dcc42 upstream. v4.10 commit 6f2ce1c6af37 ("scsi: zfcp: fix rport unblock race with LUN recovery") extended accessing parent pointer fields of struct zfcp_erp_action for tracing. If an erp_action has never been enqueued before, these parent pointer fields are uninitialized and NULL. Examples are zfcp objects freshly added to the parent object's children list, before enqueueing their first recovery subsequently. In zfcp_erp_try_rport_unblock(), we iterate such list. Accessing erp_action fields can cause a NULL pointer dereference. Since the kernel can read from lowcore on s390, it does not immediately cause a kernel page fault. Instead it can cause hangs on trying to acquire the wrong erp_action->adapter->dbf->rec_lock in zfcp_dbf_rec_action_lvl() ^bogus^ while holding already other locks with IRQs disabled. Real life example from attaching lots of LUNs in parallel on many CPUs: crash> bt 17723 PID: 17723 TASK: ... CPU: 25 COMMAND: "zfcperp0.0.1800" LOWCORE INFO: -psw : 0x0404300180000000 0x000000000038e424 -function : _raw_spin_lock_wait_flags at 38e424 ... #0 [fdde8fc90] zfcp_dbf_rec_action_lvl at 3e0004e9862 [zfcp] #1 [fdde8fce8] zfcp_erp_try_rport_unblock at 3e0004dfddc [zfcp] #2 [fdde8fd38] zfcp_erp_strategy at 3e0004e0234 [zfcp] #3 [fdde8fda8] zfcp_erp_thread at 3e0004e0a12 [zfcp] #4 [fdde8fe60] kthread at 173550 #5 [fdde8feb8] kernel_thread_starter at 10add2 zfcp_adapter zfcp_port zfcp_unit <address>, 0x404040d600000000 scsi_device NULL, returning early! zfcp_scsi_dev.status = 0x40000000 0x40000000 ZFCP_STATUS_COMMON_RUNNING crash> zfcp_unit <address> struct zfcp_unit { erp_action = { adapter = 0x0, port = 0x0, unit = 0x0, }, } zfcp_erp_action is always fully embedded into its container object. Such container object is never moved in its object tree (only add or delete). Hence, erp_action parent pointers can never change. To fix the issue, initialize the erp_action parent pointers before adding the erp_action container to any list and thus before it becomes accessible from outside of its initializing function. In order to also close the time window between zfcp_erp_setup_act() memsetting the entire erp_action to zero and setting the parent pointers again, drop the memset and instead explicitly initialize individually all erp_action fields except for parent pointers. To be extra careful not to introduce any other unintended side effect, even keep zeroing the erp_action fields for list and timer. Also double-check with WARN_ON_ONCE that erp_action parent pointers never change, so we get to know when we would deviate from previous behavior. Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: 6f2ce1c6af37 ("scsi: zfcp: fix rport unblock race with LUN recovery") Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: zfcp: trace high part of "new" 64 bit SCSI LUNSteffen Maier
commit 5d4a3d0a2ff23799b956e5962b886287614e7fad upstream. Complements debugging aspects of the otherwise functionally complete v3.17 commit 9cb78c16f5da ("scsi: use 64-bit LUNs"). While I don't have access to a target exporting 3 or 4 level LUNs, I did test it by explicitly attaching a non-existent fake 4 level LUN by means of zfcp sysfs attribute "unit_add". In order to see corresponding trace records of otherwise successful events, we had to increase the trace level of area SCSI and HBA to 6. $ echo 6 > /sys/kernel/debug/s390dbf/zfcp_0.0.1880_scsi/level $ echo 6 > /sys/kernel/debug/s390dbf/zfcp_0.0.1880_hba/level $ echo 0x4011402240334044 > \ /sys/bus/ccw/drivers/zfcp/0.0.1880/0x50050763031bd327/unit_add Example output formatted by an updated zfcpdbf from the s390-tools package interspersed with kernel messages at scsi_logging_level=4605: Timestamp : ... Area : REC Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : scsla_1 LUN : 0x4011402240334044 WWPN : 0x50050763031bd327 D_ID : 0x00...... Adapter status : 0x5400050b Port status : 0x54000001 LUN status : 0x41000000 Ready count : 0x00000001 Running count : 0x00000000 ERP want : 0x01 ERP need : 0x01 scsi 2:0:0:4630896905707208721: scsi scan: INQUIRY pass 1 length 36 scsi 2:0:0:4630896905707208721: scsi scan: INQUIRY successful with code 0x0 Timestamp : ... Area : HBA Subarea : 00 Level : 6 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : fs_norm Request ID : 0x<inquiry2-req-id> Request status : 0x00000010 FSF cmnd : 0x00000001 FSF sequence no: 0x... FSF issued : ... FSF stat : 0x00000000 FSF stat qual : 00000000 00000000 00000000 00000000 Prot stat : 0x00000001 Prot stat qual : ........ ........ 00000000 00000000 Port handle : 0x... LUN handle : 0x... | Timestamp : ... Area : SCSI Subarea : 00 Level : 6 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : rsl_nor Request ID : 0x<inquiry2-req-id> SCSI ID : 0x00000000 SCSI LUN : 0x40224011 SCSI LUN high : 0x40444033 <======================= SCSI result : 0x00000000 SCSI retries : 0x00 SCSI allowed : 0x03 SCSI scribble : 0x<inquiry2-req-id> SCSI opcode : 12000000 a4000000 00000000 00000000 FCP rsp inf cod: 0x00 FCP rsp IU : 00000000 00000000 00000000 00000000 00000000 00000000 scsi 2:0:0:4630896905707208721: scsi scan: INQUIRY pass 2 length 164 scsi 2:0:0:4630896905707208721: scsi scan: INQUIRY successful with code 0x0 scsi 2:0:0:4630896905707208721: scsi scan: peripheral device type of 31, \ no device added Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: 9cb78c16f5da ("scsi: use 64-bit LUNs") Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Reviewed-by: Jens Remus <jremus@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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: zfcp: trace HBA FSF response by default on dismiss or timedout late ↵Steffen Maier
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: 8a36e4532ea1 ("[SCSI] zfcp: enhancement of zfcp debug features") Fixes: 2e261af84cdb ("[SCSI] zfcp: Only collect FSF/HBA debug data for matching trace levels") 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: zfcp: fix payload with full FCP_RSP IU in SCSI trace recordsSteffen Maier
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: 250a1352b95e ("[SCSI] zfcp: Redesign of the debug tracing for SCSI records.") 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: zfcp: fix missing trace records for early returns in TMF eh handlersSteffen Maier
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 a1dbfddd02d2 ("[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 63caf367e1c9 ("[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: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") Fixes: 63caf367e1c9 ("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp") 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: zfcp: fix passing fsf_req to SCSI trace on TMF to correlate with HBASteffen Maier
commit 9fe5d2b2fd30aa8c7827ec62cbbe6d30df4fe3e3 upstream. Without this fix we get SCSI trace records on task management functions which cannot be correlated to HBA trace records because all fields related to the FSF request are empty (zero). Also, the FCP_RSP_IU is missing as well as any sense data if available. This was caused by v2.6.14 commit 8a36e4532ea1 ("[SCSI] zfcp: enhancement of zfcp debug features") introducing trace records for TMFs but hard coding NULL for a possibly existing TMF FSF request. The scsi_cmnd scribble is also zero or unrelated for the TMF request so it also could not lookup a suitable FSF request from there. A broken example trace record formatted with zfcpdbf from the s390-tools package: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : lr_fail Request ID : 0x0000000000000000 ^^^^^^^^^^^^^^^^ no correlation to HBA record SCSI ID : 0x<scsitarget> SCSI LUN : 0x<scsilun> SCSI result : 0x000e0000 SCSI retries : 0x00 SCSI allowed : 0x05 SCSI scribble : 0x0000000000000000 SCSI opcode : 2a000017 3bb80000 08000000 00000000 FCP rsp inf cod: 0x00 ^^ no TMF response FCP rsp IU : 00000000 00000000 00000000 00000000 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 00000000 00000000 ^^^^^^^^^^^^^^^^^ no interesting FCP_RSP_IU Sense len : ... ^^^^^^^^^^^^^^^^^^^^ no sense data length Sense info : ... ^^^^^^^^^^^^^^^^^^^^ no sense data content, even if present There are some true cases where we really do not have an FSF request: "rsl_fai" from zfcp_dbf_scsi_fail_send() called for early returns / completions in zfcp_scsi_queuecommand(), "abrt_or", "abrt_bl", "abrt_ru", "abrt_ar" from zfcp_scsi_eh_abort_handler() where we did not get as far, "lr_nres", "tr_nres" from zfcp_task_mgmt_function() where we're successful and do not need to do anything because adapter stopped. For these cases it's correct to pass NULL for fsf_req to _zfcp_dbf_scsi(). Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: 8a36e4532ea1 ("[SCSI] zfcp: enhancement of zfcp debug features") 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: zfcp: fix capping of unsuccessful GPN_FT SAN response trace recordsSteffen Maier
commit 975171b4461be296a35e83ebd748946b81cf0635 upstream. v4.9 commit aceeffbb59bb ("zfcp: trace full payload of all SAN records (req,resp,iels)") fixed trace data loss of 2.6.38 commit 2c55b750a884 ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.") necessary for problem determination, e.g. to see the currently active zone set during automatic port scan. While it already saves space by not dumping any empty residual entries of the large successful GPN_FT response (4 pages), there are seldom cases where the GPN_FT response is unsuccessful and likely does not have FC_NS_FID_LAST set in fp_flags so we did not cap the trace record. We typically see such case for an initiator WWPN, which is not in any zone. Cap unsuccessful responses to at least the actual basic CT_IU response plus whatever fits the SAN trace record built-in "payload" buffer just in case there's trailing information of which we would at least see the existence and its beginning. In order not to erroneously cap successful responses, we need to swap calling the trace function and setting the CT / ELS status to success (0). Example trace record pair formatted with zfcpdbf: Timestamp : ... Area : SAN Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : fssct_1 Request ID : 0x<request_id> Destination ID : 0x00fffffc SAN req short : 01000000 fc020000 01720ffc 00000000 00000008 SAN req length : 20 | Timestamp : ... Area : SAN Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 2 Tag : fsscth2 Request ID : 0x<request_id> Destination ID : 0x00fffffc SAN resp short : 01000000 fc020000 80010000 00090700 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] SAN resp length: 16384 San resp info : 01000000 fc020000 80010000 00090700 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] 00000000 00000000 00000000 00000000 [trailing info] The fix saves all but one of the previously associated 64 PAYload trace record chunks of size 256 bytes each. Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: aceeffbb59bb ("zfcp: trace full payload of all SAN records (req,resp,iels)") Fixes: 2c55b750a884 ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.") 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: zfcp: add handling for FCP_RESID_OVER to the fcp ingress pathBenjamin Block
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: 553448f6c483 ("[SCSI] zfcp: Message cleanup") Fixes: ea127f975424 ("[PATCH] s390 (7/7): zfcp host adapter.") (tglx/history.git) Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: zfcp: fix queuecommand for scsi_eh commands when DIX enabledSteffen Maier
commit 71b8e45da51a7b64a23378221c0a5868bd79da4f upstream. Since commit db007fc5e20c ("[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 ef3eb71d8ba4 ("[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: ef3eb71d8ba4 ("[SCSI] zfcp: Introduce experimental support for DIF/DIX") 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07s390/qeth: avoid null pointer dereference on OSNJulian Wiedmann
[ Upstream commit 25e2c341e7818a394da9abc403716278ee646014 ] Access card->dev only after checking whether's its valid. Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07s390/qeth: unbreak OSM and OSN supportJulian Wiedmann
[ Upstream commit 2d2ebb3ed0c6acfb014f98e427298673a5d07b82 ] commit b4d72c08b358 ("qeth: bridgeport support - basic control") broke the support for OSM and OSN devices as follows: As OSM and OSN are L2 only, qeth_core_probe_device() does an early setup by loading the l2 discipline and calling qeth_l2_probe_device(). In this context, adding the l2-specific bridgeport sysfs attributes via qeth_l2_create_device_attributes() hits a BUG_ON in fs/sysfs/group.c, since the basic sysfs infrastructure for the device hasn't been established yet. Note that OSN actually has its own unique sysfs attributes (qeth_osn_devtype), so the additional attributes shouldn't be created at all. For OSM, add a new qeth_l2_devtype that contains all the common and l2-specific sysfs attributes. When qeth_core_probe_device() does early setup for OSM or OSN, assign the corresponding devtype so that the ccwgroup probe code creates the full set of sysfs attributes. This allows us to skip qeth_l2_create_device_attributes() in case of an early setup. Any device that can't do early setup will initially have only the generic sysfs attributes, and when it's probed later qeth_l2_probe_device() adds the l2-specific attributes. If an early-setup device is removed (by calling ccwgroup_ungroup()), device_unregister() will - using the devtype - delete the l2-specific attributes before qeth_l2_remove_device() is called. So make sure to not remove them twice. What complicates the issue is that qeth_l2_probe_device() and qeth_l2_remove_device() is also called on a device when its layer2 attribute changes (ie. its layer mode is switched). For early-setup devices this wouldn't work properly - we wouldn't remove the l2-specific attributes when switching to L3. But switching the layer mode doesn't actually make any sense; we already decided that the device can only operate in L2! So just refuse to switch the layer mode on such devices. Note that OSN doesn't have a layer2 attribute, so we only need to special-case OSM. Based on an initial patch by Ursula Braun. Fixes: b4d72c08b358 ("qeth: bridgeport support - basic control") Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07s390/qeth: handle sysfs error during initializationUrsula Braun
[ Upstream commit 9111e7880ccf419548c7b0887df020b08eadb075 ] When setting up the device from within the layer discipline's probe routine, creating the layer-specific sysfs attributes can fail. Report this error back to the caller, and handle it by releasing the layer discipline. Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com> [jwi: updated commit msg, moved an OSN change to a subsequent patch] Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-30s390/zcrypt: Introduce CEX6 tolerationSumit Semwal
From: Harald Freudenberger <freude@linux.vnet.ibm.com> [ Upstream commit b3e8652bcbfa04807e44708d4d0c8cdad39c9215 ] Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-15s390/dcssblk: fix device size calculation in dcssblk_direct_access()Gerald Schaefer
commit a63f53e34db8b49675448d03ae324f6c5bc04fe6 upstream. Since commit dd22f551 "block: Change direct_access calling convention", the device size calculation in dcssblk_direct_access() is off-by-one. This results in bdev_direct_access() always returning -ENXIO because the returned value is not page aligned. Fix this by adding 1 to the dev_sz calculation. Fixes: dd22f551 ("block: Change direct_access calling convention") 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>
2017-03-15s390/qdio: clear DSCI prior to scanning multiple input queuesJulian Wiedmann
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: 104ea556ee7f ("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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14scsi: zfcp: fix use-after-free by not tracing WKA port open/close on failed sendSteffen Maier
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-09s390/vmlogrdr: fix IUCV buffer allocationGerald Schaefer
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-09scsi: zfcp: fix rport unblock race with LUN recoverySteffen Maier
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: 8830271c4819 ("[SCSI] zfcp: Dont fail SCSI commands when transitioning to blocked fc_rport") Fixes: a2fa0aede07c ("[SCSI] zfcp: Block FC transport rports early on errors") Fixes: 5f852be9e11d ("[SCSI] zfcp: Fix deadlock between zfcp ERP and SCSI") Fixes: 338151e06608 ("[SCSI] zfcp: make use of fc_remote_port_delete when target port is unavailable") Fixes: 3859f6a248cb ("[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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-09scsi: zfcp: do not trace pure benign residual HBA responses at default levelSteffen Maier
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: a54ca0f62f95 ("[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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-09scsi: zfcp: fix use-after-"free" in FC ingress path after TMFBenjamin Block
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31s390/con3270: fix insufficient space paddingSascha Silbe
commit 6cd997db911f28f2510b771691270c52b63ed2e6 upstream. con3270 contains an optimisation that reduces the amount of data to be transmitted to the 3270 terminal by putting a Repeat to Address (RA) order into the data stream. The RA order itself takes up space, so con3270 only uses it if there's enough space left in the line buffer. Otherwise it just pads out the line manually. For lines that were _just_ short enough that the RA order still fit in the line buffer, the line was instead padded with an insufficient amount of spaces. This was caused by examining the size of the allocated line buffer rather than the length of the string to be displayed. For con3270_cline_end(), we just compare against the line length. For con3270_update_string() however that isn't available anymore, so we check whether the Repeat to Address order is present. Fixes: f51320a5 ("[PATCH] s390: new 3270 driver.") (tglx/history.git) Tested-by: Jing Liu <liujbjl@linux.vnet.ibm.com> Tested-by: Yang Chen <bjcyang@linux.vnet.ibm.com> Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31s390/con3270: fix use of uninitialised dataSascha Silbe
commit c14f2aac7aa147861793eed9f41f91dd530f0be1 upstream. con3270 contains an optimisation that reduces the amount of data to be transmitted to the 3270 terminal by putting a Repeat to Address (RA) order into the data stream. The RA order itself takes up space, so con3270 only uses it if there's enough space left in the line buffer. Otherwise it just pads out the line manually. For lines too long to include the RA order, one byte was left uninitialised. This was caused by an off-by-one bug in the loop that pads out the line. Since the buffer is allocated from a common pool, the single byte left uninitialised contained some previous buffer content. Usually this was just a space or some character (which can result in clutter but is otherwise harmless). Sometimes, however, it was a Repeat to Address order, messing up the entire screen layout and causing the display to send the entire buffer content on every keystroke. Fixes: f51320a5 ("[PATCH] s390: new 3270 driver.") (tglx/history.git) Reported-by: Liu Jing <liujbjl@linux.vnet.ibm.com> Tested-by: Jing Liu <liujbjl@linux.vnet.ibm.com> Tested-by: Yang Chen <bjcyang@linux.vnet.ibm.com> Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31s390/cio: fix accidental interrupt enabling during resumeSebastian Ott
commit d53c51f26145657aa7c55fa396f93677e613548d upstream. Since commit 9f3d6d7 chsc_get_channel_measurement_chars is called with interrupts disabled during resume from hibernate. Since this function used spin_unlock_irq, interrupts have been enabled accidentally. Fix this by using the irqsave variant. Since we can't guarantee the IRQ-enablement state for all (future/ external) callers, change the locking in related functions to prevent similar bugs in the future. Fixes: 9f3d6d7 ("s390/cio: update measurement characteristics") Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28scsi: zfcp: spin_lock_irqsave() is not nestableDan Carpenter
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28zfcp: trace full payload of all SAN records (req,resp,iels)Steffen Maier
commit aceeffbb59bb91404a0bda32a542d7ebf878433a upstream. This was lost with commit 2c55b750a884b86dea8b4cc5f15e1484cc47a25c ("[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: 2c55b750a884 ("[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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28zfcp: fix payload trace length for SAN request&responseSteffen Maier
commit 94db3725f049ead24c96226df4a4fb375b880a77 upstream. commit 2c55b750a884b86dea8b4cc5f15e1484cc47a25c ("[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: 2c55b750a884 ("[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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28zfcp: fix D_ID field with actual value on tracing SAN responsesSteffen Maier
commit 771bf03537ddfa4a4dde62ef9dfbc82e4f77ab20 upstream. With commit 2c55b750a884b86dea8b4cc5f15e1484cc47a25c ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.") we lost the N_Port-ID where an ELS response comes from. With commit 7c7dc196814b9e1d5cc254dc579a5fa78ae524f7 ("[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: 2c55b750a884 ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.") Fixes: 7c7dc196814b ("[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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28zfcp: restore tracing of handle for port and LUN with HBA recordsSteffen Maier
commit 7c964ffe586bc0c3d9febe9bf97a2e4b2866e5b7 upstream. This information was lost with commit a54ca0f62f953898b05549391ac2a8a4dad6482b ("[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: a54ca0f62f95 ("[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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>