<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/s390, branch v4.9.124</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>scsi: zfcp: fix missing REC trigger trace on enqueue without ERP thread</title>
<updated>2018-07-03T09:23:12+00:00</updated>
<author>
<name>Steffen Maier</name>
<email>maier@linux.ibm.com</email>
</author>
<published>2018-05-17T17:14:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c6751cb1e828d7aa93cedfcee65534318278713e'/>
<id>c6751cb1e828d7aa93cedfcee65534318278713e</id>
<content type='text'>
commit 6a76550841d412330bd86aed3238d1888ba70f0e upstream.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : .......
LUN            : 0x...
WWPN           : 0x...
D_ID           : 0x...
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x...
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x0.                   ZFCP_ERP_ACTION_REOPEN_...
ERP need       : 0xc0                   ZFCP_ERP_ACTION_NONE

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6a76550841d412330bd86aed3238d1888ba70f0e upstream.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : .......
LUN            : 0x...
WWPN           : 0x...
D_ID           : 0x...
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x...
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x0.                   ZFCP_ERP_ACTION_REOPEN_...
ERP need       : 0xc0                   ZFCP_ERP_ACTION_NONE

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: zfcp: fix missing REC trigger trace for all objects in ERP_FAILED</title>
<updated>2018-07-03T09:23:12+00:00</updated>
<author>
<name>Steffen Maier</name>
<email>maier@linux.ibm.com</email>
</author>
<published>2018-05-17T17:14:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2df7e6f33c64c61e9a33dbbed6bed4af78e94d67'/>
<id>2df7e6f33c64c61e9a33dbbed6bed4af78e94d67</id>
<content type='text'>
commit 8c3d20aada70042a39c6a6625be037c1472ca610 upstream.

That other commit introduced an inconsistency because it would trace on
ERP_FAILED for all callers of port forced reopen triggers (not just
terminate_rport_io), but it would not trace on ERP_FAILED for all callers of
other ERP triggers such as adapter, port regular, LUN.

Therefore, generalize that other commit. zfcp_erp_action_enqueue() already
had two early outs which re-used the one zfcp_dbf_rec_trig() call.  All ERP
trigger functions finally run through zfcp_erp_action_enqueue().  So move
the special handling for ZFCP_STATUS_COMMON_ERP_FAILED into
zfcp_erp_action_enqueue() and add another early out with new trace marker
for pseudo ERP need in this case. This removes all early returns from all
ERP trigger functions so we always end up at zfcp_dbf_rec_trig().

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : .......
LUN            : 0x...
WWPN           : 0x...
D_ID           : 0x...
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x...
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x0.                   ZFCP_ERP_ACTION_REOPEN_...
ERP need       : 0xe0                   ZFCP_ERP_ACTION_FAILED

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8c3d20aada70042a39c6a6625be037c1472ca610 upstream.

That other commit introduced an inconsistency because it would trace on
ERP_FAILED for all callers of port forced reopen triggers (not just
terminate_rport_io), but it would not trace on ERP_FAILED for all callers of
other ERP triggers such as adapter, port regular, LUN.

Therefore, generalize that other commit. zfcp_erp_action_enqueue() already
had two early outs which re-used the one zfcp_dbf_rec_trig() call.  All ERP
trigger functions finally run through zfcp_erp_action_enqueue().  So move
the special handling for ZFCP_STATUS_COMMON_ERP_FAILED into
zfcp_erp_action_enqueue() and add another early out with new trace marker
for pseudo ERP need in this case. This removes all early returns from all
ERP trigger functions so we always end up at zfcp_dbf_rec_trig().

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : .......
LUN            : 0x...
WWPN           : 0x...
D_ID           : 0x...
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x...
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x0.                   ZFCP_ERP_ACTION_REOPEN_...
ERP need       : 0xe0                   ZFCP_ERP_ACTION_FAILED

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: zfcp: fix missing REC trigger trace on terminate_rport_io for ERP_FAILED</title>
<updated>2018-07-03T09:23:12+00:00</updated>
<author>
<name>Steffen Maier</name>
<email>maier@linux.ibm.com</email>
</author>
<published>2018-05-17T17:14:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=21224f6f135ab267b07729f3274fcfc028b3ace0'/>
<id>21224f6f135ab267b07729f3274fcfc028b3ace0</id>
<content type='text'>
commit d70aab55924b44f213fec2b900b095430b33eec6 upstream.

For problem determination we always want to see when we were invoked on the
terminate_rport_io callback whether we perform something or not.

Temporal event sequence of interest with a long fast_io_fail_tmo of 27 sec:

loose remote port

t   workqueue
[s] zfcp_q_&lt;dev&gt;       IRQ                 zfcperp&lt;dev&gt;

=== ================== =================== ============================

  0                    recv RSCN
                       q p.test_link_work
    block rport
     start fast_io_fail_tmo
    send ADISC ELS
  4                    recv ADISC fail
                       block zfcp_port
                                           port forced reopen
                                           send open port
 12                    recv open port fail
                                           q p.gid_pn_work
                                           zfcp_erp_wakeup
                                           (zfcp_erp_wait would return)
    GID_PN fail

Before this point, we got a SCSI trace with tag "sctrpi1" on fast_io_fail,
e.g. with the typical 5 sec setting.

    port.status |= ERP_FAILED

If fast_io_fail_tmo triggers after this point, we missed a SCSI trace.

    workqueue
    fc_dl_&lt;host&gt;
    ==================
 27 fc_timeout_fail_rport_io
    fc_terminate_rport_io
    zfcp_scsi_terminate_rport_io
    zfcp_erp_port_forced_reopen
    _zfcp_erp_port_forced_reopen
     if (port.status &amp; ERP_FAILED)
      return;

Therefore, write a trace before above early return.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : sctrpi1                SCSI terminate rport I/O
LUN            : 0xffffffffffffffff                     none (invalid)
WWPN           : 0x&lt;wwpn&gt;
D_ID           : 0x&lt;n_port_id&gt;
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x00000000                             none (invalid)
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x03                   ZFCP_ERP_ACTION_REOPEN_PORT_FORCED
ERP need       : 0xe0                   ZFCP_ERP_ACTION_FAILED

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit d70aab55924b44f213fec2b900b095430b33eec6 upstream.

For problem determination we always want to see when we were invoked on the
terminate_rport_io callback whether we perform something or not.

Temporal event sequence of interest with a long fast_io_fail_tmo of 27 sec:

loose remote port

t   workqueue
[s] zfcp_q_&lt;dev&gt;       IRQ                 zfcperp&lt;dev&gt;

=== ================== =================== ============================

  0                    recv RSCN
                       q p.test_link_work
    block rport
     start fast_io_fail_tmo
    send ADISC ELS
  4                    recv ADISC fail
                       block zfcp_port
                                           port forced reopen
                                           send open port
 12                    recv open port fail
                                           q p.gid_pn_work
                                           zfcp_erp_wakeup
                                           (zfcp_erp_wait would return)
    GID_PN fail

Before this point, we got a SCSI trace with tag "sctrpi1" on fast_io_fail,
e.g. with the typical 5 sec setting.

    port.status |= ERP_FAILED

If fast_io_fail_tmo triggers after this point, we missed a SCSI trace.

    workqueue
    fc_dl_&lt;host&gt;
    ==================
 27 fc_timeout_fail_rport_io
    fc_terminate_rport_io
    zfcp_scsi_terminate_rport_io
    zfcp_erp_port_forced_reopen
    _zfcp_erp_port_forced_reopen
     if (port.status &amp; ERP_FAILED)
      return;

Therefore, write a trace before above early return.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1                      ZFCP_DBF_REC_TRIG
Tag            : sctrpi1                SCSI terminate rport I/O
LUN            : 0xffffffffffffffff                     none (invalid)
WWPN           : 0x&lt;wwpn&gt;
D_ID           : 0x&lt;n_port_id&gt;
Adapter status : 0x...
Port status    : 0x...
LUN status     : 0x00000000                             none (invalid)
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x03                   ZFCP_ERP_ACTION_REOPEN_PORT_FORCED
ERP need       : 0xe0                   ZFCP_ERP_ACTION_FAILED

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: zfcp: fix missing REC trigger trace on terminate_rport_io early return</title>
<updated>2018-07-03T09:23:12+00:00</updated>
<author>
<name>Steffen Maier</name>
<email>maier@linux.ibm.com</email>
</author>
<published>2018-05-17T17:14:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=48ae373c57f009b32a03637e0809fabd9132fe81'/>
<id>48ae373c57f009b32a03637e0809fabd9132fe81</id>
<content type='text'>
commit 96d9270499471545048ed8a6d7f425a49762283d upstream.

get_device() and its internally used kobject_get() only return NULL if they
get passed NULL as argument. zfcp_get_port_by_wwpn() loops over
adapter-&gt;port_list so the iteration variable port is always non-NULL.
Struct device is embedded in struct zfcp_port so &amp;port-&gt;dev is always
non-NULL. This is the argument to get_device().  However, if we get an
fc_rport in terminate_rport_io() for which we cannot find a match within
zfcp_get_port_by_wwpn(), the latter can return NULL.  v2.6.30 commit
70932935b61e ("[SCSI] zfcp: Fix oops when port disappears") introduced an
early return without adding a trace record for this case.  Even if we don't
need recovery in this case, for debugging we should still see that our
callback was invoked originally by scsi_transport_fc.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : sctrpin        SCSI terminate rport I/O, no zfcp port
LUN            : 0xffffffffffffffff                     none (invalid)
WWPN           : 0x&lt;wwpn&gt;               WWPN
D_ID           : 0x&lt;n_port_id&gt;          N_Port-ID
Adapter status : 0x...
Port status    : 0xffffffff             unknown (-1)
LUN status     : 0x00000000                             none (invalid)
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x03                   ZFCP_ERP_ACTION_REOPEN_PORT_FORCED
ERP need       : 0xc0                   ZFCP_ERP_ACTION_NONE

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Fixes: 70932935b61e ("[SCSI] zfcp: Fix oops when port disappears")
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 96d9270499471545048ed8a6d7f425a49762283d upstream.

get_device() and its internally used kobject_get() only return NULL if they
get passed NULL as argument. zfcp_get_port_by_wwpn() loops over
adapter-&gt;port_list so the iteration variable port is always non-NULL.
Struct device is embedded in struct zfcp_port so &amp;port-&gt;dev is always
non-NULL. This is the argument to get_device().  However, if we get an
fc_rport in terminate_rport_io() for which we cannot find a match within
zfcp_get_port_by_wwpn(), the latter can return NULL.  v2.6.30 commit
70932935b61e ("[SCSI] zfcp: Fix oops when port disappears") introduced an
early return without adding a trace record for this case.  Even if we don't
need recovery in this case, for debugging we should still see that our
callback was invoked originally by scsi_transport_fc.

Example trace record formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : REC
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : sctrpin        SCSI terminate rport I/O, no zfcp port
LUN            : 0xffffffffffffffff                     none (invalid)
WWPN           : 0x&lt;wwpn&gt;               WWPN
D_ID           : 0x&lt;n_port_id&gt;          N_Port-ID
Adapter status : 0x...
Port status    : 0xffffffff             unknown (-1)
LUN status     : 0x00000000                             none (invalid)
Ready count    : 0x...
Running count  : 0x...
ERP want       : 0x03                   ZFCP_ERP_ACTION_REOPEN_PORT_FORCED
ERP need       : 0xc0                   ZFCP_ERP_ACTION_NONE

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Fixes: 70932935b61e ("[SCSI] zfcp: Fix oops when port disappears")
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: zfcp: fix misleading REC trigger trace where erp_action setup failed</title>
<updated>2018-07-03T09:23:12+00:00</updated>
<author>
<name>Steffen Maier</name>
<email>maier@linux.ibm.com</email>
</author>
<published>2018-05-17T17:14:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b0c2fc11ced965b01f174f69ecfac7feca48bc84'/>
<id>b0c2fc11ced965b01f174f69ecfac7feca48bc84</id>
<content type='text'>
commit 512857a795cbbda5980efa4cdb3c0b6602330408 upstream.

If a SCSI device is deleted during scsi_eh host reset, we cannot get a
reference to the SCSI device anymore since scsi_device_get returns !=0 by
design. Assuming the recovery of adapter and port(s) was successful,
zfcp_erp_strategy_followup_success() attempts to trigger a LUN reset for the
half-gone SCSI device. Unfortunately, it causes the following confusing
trace record which states that zfcp will do a LUN recovery as "ERP need" is
ZFCP_ERP_ACTION_REOPEN_LUN == 1 and equals "ERP want".

Old example trace record formatted with zfcpdbf from s390-tools:

Tag:           : ersfs_3 ERP, trigger, unit reopen, port reopen succeeded
LUN            : 0x&lt;FCP_LUN&gt;
WWPN           : 0x&lt;WWPN&gt;
D_ID           : 0x&lt;N_Port-ID&gt;
Adapter status : 0x5400050b
Port status    : 0x54000001
LUN status     : 0x40000000     ZFCP_STATUS_COMMON_RUNNING
                                but not ZFCP_STATUS_COMMON_UNBLOCKED as it
                                was closed on close part of adapter reopen
ERP want       : 0x01
ERP need       : 0x01           misleading

However, zfcp_erp_setup_act() returns NULL as it cannot get the reference.
Hence, zfcp_erp_action_enqueue() takes an early goto out and _NO_ recovery
actually happens.

We always do want the recovery trigger trace record even if no erp_action
could be enqueued as in this case. For other cases where we did not enqueue
an erp_action, 'need' has always been zero to indicate this. In order to
indicate above goto out, introduce an eyecatcher "flag" to mark the "ERP
need" as 'not needed' but still keep the information which erp_action type,
that zfcp_erp_required_act() had decided upon, is needed.  0xc_ is chosen to
be visibly different from 0x0_ in "ERP want".

New example trace record formatted with zfcpdbf from s390-tools:

Tag:           : ersfs_3 ERP, trigger, unit reopen, port reopen succeeded
LUN            : 0x&lt;FCP_LUN&gt;
WWPN           : 0x&lt;WWPN&gt;
D_ID           : 0x&lt;N_Port-ID&gt;
Adapter status : 0x5400050b
Port status    : 0x54000001
LUN status     : 0x40000000
ERP want       : 0x01
ERP need       : 0xc1           would need LUN ERP, but no action set up
                   ^

Before v2.6.38 commit ae0904f60fab ("[SCSI] zfcp: Redesign of the debug
tracing for recovery actions.") we could detect this case because the
"erp_action" field in the trace was NULL. The rework removed erp_action as
argument and field from the trace.

This patch here is for tracing. A fix to allow LUN recovery in the case at
hand is a topic for a separate patch.

See also commit fdbd1c5e27da ("[SCSI] zfcp: Allow running unit/LUN shutdown
without acquiring reference") for a similar case and background info.

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Fixes: ae0904f60fab ("[SCSI] zfcp: Redesign of the debug tracing for recovery actions.")
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 512857a795cbbda5980efa4cdb3c0b6602330408 upstream.

If a SCSI device is deleted during scsi_eh host reset, we cannot get a
reference to the SCSI device anymore since scsi_device_get returns !=0 by
design. Assuming the recovery of adapter and port(s) was successful,
zfcp_erp_strategy_followup_success() attempts to trigger a LUN reset for the
half-gone SCSI device. Unfortunately, it causes the following confusing
trace record which states that zfcp will do a LUN recovery as "ERP need" is
ZFCP_ERP_ACTION_REOPEN_LUN == 1 and equals "ERP want".

Old example trace record formatted with zfcpdbf from s390-tools:

Tag:           : ersfs_3 ERP, trigger, unit reopen, port reopen succeeded
LUN            : 0x&lt;FCP_LUN&gt;
WWPN           : 0x&lt;WWPN&gt;
D_ID           : 0x&lt;N_Port-ID&gt;
Adapter status : 0x5400050b
Port status    : 0x54000001
LUN status     : 0x40000000     ZFCP_STATUS_COMMON_RUNNING
                                but not ZFCP_STATUS_COMMON_UNBLOCKED as it
                                was closed on close part of adapter reopen
ERP want       : 0x01
ERP need       : 0x01           misleading

However, zfcp_erp_setup_act() returns NULL as it cannot get the reference.
Hence, zfcp_erp_action_enqueue() takes an early goto out and _NO_ recovery
actually happens.

We always do want the recovery trigger trace record even if no erp_action
could be enqueued as in this case. For other cases where we did not enqueue
an erp_action, 'need' has always been zero to indicate this. In order to
indicate above goto out, introduce an eyecatcher "flag" to mark the "ERP
need" as 'not needed' but still keep the information which erp_action type,
that zfcp_erp_required_act() had decided upon, is needed.  0xc_ is chosen to
be visibly different from 0x0_ in "ERP want".

New example trace record formatted with zfcpdbf from s390-tools:

Tag:           : ersfs_3 ERP, trigger, unit reopen, port reopen succeeded
LUN            : 0x&lt;FCP_LUN&gt;
WWPN           : 0x&lt;WWPN&gt;
D_ID           : 0x&lt;N_Port-ID&gt;
Adapter status : 0x5400050b
Port status    : 0x54000001
LUN status     : 0x40000000
ERP want       : 0x01
ERP need       : 0xc1           would need LUN ERP, but no action set up
                   ^

Before v2.6.38 commit ae0904f60fab ("[SCSI] zfcp: Redesign of the debug
tracing for recovery actions.") we could detect this case because the
"erp_action" field in the trace was NULL. The rework removed erp_action as
argument and field from the trace.

This patch here is for tracing. A fix to allow LUN recovery in the case at
hand is a topic for a separate patch.

See also commit fdbd1c5e27da ("[SCSI] zfcp: Allow running unit/LUN shutdown
without acquiring reference") for a similar case and background info.

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Fixes: ae0904f60fab ("[SCSI] zfcp: Redesign of the debug tracing for recovery actions.")
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: zfcp: fix missing SCSI trace for retry of abort / scsi_eh TMF</title>
<updated>2018-07-03T09:23:11+00:00</updated>
<author>
<name>Steffen Maier</name>
<email>maier@linux.ibm.com</email>
</author>
<published>2018-05-17T17:14:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=97d3625bdd43e6816b179ea56a7aa58060069eee'/>
<id>97d3625bdd43e6816b179ea56a7aa58060069eee</id>
<content type='text'>
commit 81979ae63e872ef650a7197f6ce6590059d37172 upstream.

We already have a SCSI trace for the end of abort and scsi_eh TMF. Due to
zfcp_erp_wait() and fc_block_scsi_eh() time can pass between the start of
our eh callback and an actual send/recv of an abort / TMF request.  In order
to see the temporal sequence including any abort / TMF send retries, add a
trace before the above two blocking functions.  This supports problem
determination with scsi_eh and parallel zfcp ERP.

No need to explicitly trace the beginning of our eh callback, since we
typically can send an abort / TMF and see its HBA response (in the worst
case, it's a pseudo response on dismiss all of adapter recovery, e.g. due to
an FSF request timeout [fsrth_1] of the abort / TMF). If we cannot send, we
now get a trace record for the first "abrt_wt" or "[lt]r_wait" which denotes
almost the beginning of the callback.

No need to explicitly trace the wakeup after the above two blocking
functions because the next retry loop causes another trace in any case and
that is sufficient.

Example trace records formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : abrt_wt        abort, before zfcp_erp_wait()
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0x&lt;scsi_id&gt;
SCSI LUN       : 0x&lt;scsi_lun&gt;
SCSI LUN high  : 0x&lt;scsi_lun_high&gt;
SCSI result    : 0x&lt;scsi_result_of_cmd_to_be_aborted&gt;
SCSI retries   : 0x&lt;retries_of_cmd_to_be_aborted&gt;
SCSI allowed   : 0x&lt;allowed_retries_of_cmd_to_be_aborted&gt;
SCSI scribble  : 0x&lt;req_id_of_cmd_to_be_aborted&gt;
SCSI opcode    : &lt;CDB_of_cmd_to_be_aborted&gt;
FCP rsp inf cod: 0x..                                   none (invalid)
FCP rsp IU     : ...                                    none (invalid)

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : lr_wait        LUN reset, before zfcp_erp_wait()
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0x&lt;scsi_id&gt;
SCSI LUN       : 0x&lt;scsi_lun&gt;
SCSI LUN high  : 0x&lt;scsi_lun_high&gt;
SCSI result    : 0x...                                  unrelated
SCSI retries   : 0x..                                   unrelated
SCSI allowed   : 0x..                                   unrelated
SCSI scribble  : 0x...                                  unrelated
SCSI opcode    : ...                                    unrelated
FCP rsp inf cod: 0x..                                   none (invalid)
FCP rsp IU     : ...                                    none (invalid)

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Fixes: 63caf367e1c9 ("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp")
Fixes: af4de36d911a ("[SCSI] zfcp: Block scsi_eh thread for rport state BLOCKED")
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 81979ae63e872ef650a7197f6ce6590059d37172 upstream.

We already have a SCSI trace for the end of abort and scsi_eh TMF. Due to
zfcp_erp_wait() and fc_block_scsi_eh() time can pass between the start of
our eh callback and an actual send/recv of an abort / TMF request.  In order
to see the temporal sequence including any abort / TMF send retries, add a
trace before the above two blocking functions.  This supports problem
determination with scsi_eh and parallel zfcp ERP.

No need to explicitly trace the beginning of our eh callback, since we
typically can send an abort / TMF and see its HBA response (in the worst
case, it's a pseudo response on dismiss all of adapter recovery, e.g. due to
an FSF request timeout [fsrth_1] of the abort / TMF). If we cannot send, we
now get a trace record for the first "abrt_wt" or "[lt]r_wait" which denotes
almost the beginning of the callback.

No need to explicitly trace the wakeup after the above two blocking
functions because the next retry loop causes another trace in any case and
that is sufficient.

Example trace records formatted with zfcpdbf from s390-tools:

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : abrt_wt        abort, before zfcp_erp_wait()
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0x&lt;scsi_id&gt;
SCSI LUN       : 0x&lt;scsi_lun&gt;
SCSI LUN high  : 0x&lt;scsi_lun_high&gt;
SCSI result    : 0x&lt;scsi_result_of_cmd_to_be_aborted&gt;
SCSI retries   : 0x&lt;retries_of_cmd_to_be_aborted&gt;
SCSI allowed   : 0x&lt;allowed_retries_of_cmd_to_be_aborted&gt;
SCSI scribble  : 0x&lt;req_id_of_cmd_to_be_aborted&gt;
SCSI opcode    : &lt;CDB_of_cmd_to_be_aborted&gt;
FCP rsp inf cod: 0x..                                   none (invalid)
FCP rsp IU     : ...                                    none (invalid)

Timestamp      : ...
Area           : SCSI
Subarea        : 00
Level          : 1
Exception      : -
CPU ID         : ..
Caller         : 0x...
Record ID      : 1
Tag            : lr_wait        LUN reset, before zfcp_erp_wait()
Request ID     : 0x0000000000000000                     none (invalid)
SCSI ID        : 0x&lt;scsi_id&gt;
SCSI LUN       : 0x&lt;scsi_lun&gt;
SCSI LUN high  : 0x&lt;scsi_lun_high&gt;
SCSI result    : 0x...                                  unrelated
SCSI retries   : 0x..                                   unrelated
SCSI allowed   : 0x..                                   unrelated
SCSI scribble  : 0x...                                  unrelated
SCSI opcode    : ...                                    unrelated
FCP rsp inf cod: 0x..                                   none (invalid)
FCP rsp IU     : ...                                    none (invalid)

Signed-off-by: Steffen Maier &lt;maier@linux.ibm.com&gt;
Fixes: 63caf367e1c9 ("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp")
Fixes: af4de36d911a ("[SCSI] zfcp: Block scsi_eh thread for rport state BLOCKED")
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handler</title>
<updated>2018-07-03T09:23:11+00:00</updated>
<author>
<name>Steffen Maier</name>
<email>maier@linux.ibm.com</email>
</author>
<published>2018-05-17T17:14:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9779f499d88f55df72cc504b830115aecea9cfbe'/>
<id>9779f499d88f55df72cc504b830115aecea9cfbe</id>
<content type='text'>
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 &lt;maier@linux.ibm.com&gt;
Fixes: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh")
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Jens Remus &lt;jremus@linux.ibm.com&gt;
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;maier@linux.ibm.com&gt;
Fixes: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh")
Cc: &lt;stable@vger.kernel.org&gt; #2.6.38+
Reviewed-by: Jens Remus &lt;jremus@linux.ibm.com&gt;
Reviewed-by: Benjamin Block &lt;bblock@linux.ibm.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>s390/cio: clear timer when terminating driver I/O</title>
<updated>2018-05-30T05:50:29+00:00</updated>
<author>
<name>Sebastian Ott</name>
<email>sebott@linux.vnet.ibm.com</email>
</author>
<published>2018-02-12T11:01:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f18fb14521dd9d46b9d02bf7caf25ac100ff09f9'/>
<id>f18fb14521dd9d46b9d02bf7caf25ac100ff09f9</id>
<content type='text'>
[ 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 &lt;sebott@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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 &lt;sebott@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/cio: fix return code after missing interrupt</title>
<updated>2018-05-30T05:50:29+00:00</updated>
<author>
<name>Sebastian Ott</name>
<email>sebott@linux.vnet.ibm.com</email>
</author>
<published>2018-02-07T12:18:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b912a541d4ca6bafc7d6343f5656eb8652015b9d'/>
<id>b912a541d4ca6bafc7d6343f5656eb8652015b9d</id>
<content type='text'>
[ 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 &lt;jwi@linux.vnet.ibm.com&gt;
Signed-off-by: Sebastian Ott &lt;sebott@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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 &lt;jwi@linux.vnet.ibm.com&gt;
Signed-off-by: Sebastian Ott &lt;sebott@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/cio: fix ccw_device_start_timeout API</title>
<updated>2018-05-30T05:50:29+00:00</updated>
<author>
<name>Sebastian Ott</name>
<email>sebott@linux.vnet.ibm.com</email>
</author>
<published>2018-02-06T13:59:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9a8c6a26da1351885d2cd64f127102e7eafcb8b3'/>
<id>9a8c6a26da1351885d2cd64f127102e7eafcb8b3</id>
<content type='text'>
[ Upstream commit f97a6b6c47d2f329a24f92cc0ca3c6df5727ba73 ]

There are cases a device driver can't start IO because the device is
currently in use by cio. In this case the device driver is notified
when the device is usable again.

Using ccw_device_start_timeout we would set the timeout (and change
an existing timeout) before we test for internal usage. Worst case
this could lead to an unexpected timer deletion.

Fix this by setting the timeout after we test for internal usage.

Signed-off-by: Sebastian Ott &lt;sebott@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f97a6b6c47d2f329a24f92cc0ca3c6df5727ba73 ]

There are cases a device driver can't start IO because the device is
currently in use by cio. In this case the device driver is notified
when the device is usable again.

Using ccw_device_start_timeout we would set the timeout (and change
an existing timeout) before we test for internal usage. Worst case
this could lead to an unexpected timer deletion.

Fix this by setting the timeout after we test for internal usage.

Signed-off-by: Sebastian Ott &lt;sebott@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
