Commit Graph

704772 Commits

Author SHA1 Message Date
Finn Thain
d60e9eec95 scsi: esp_scsi: Always clear msg_out_len after MESSAGE OUT phase
After sending a message, always clear esp->msg_out_len. Otherwise,
eh_abort_handler may subsequently fail to send an ABORT TASK SET
message.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:55:35 -04:00
Finn Thain
c69edff5c5 scsi: esp_scsi: Avoid sending ABORT TASK SET messages
If an LLD aborts a task set, it should complete the affected commands
with the appropriate result code. In a couple of cases esp_scsi doesn't
do so.

When the initiator receives an unhandled message, just respond by sending
a MESSAGE REJECT instead of ABORT TASK SET, and thus avoid the issue.

OTOH, a MESSAGE REJECT sent by a target can be taken as an indication
that the initiator messed up somehow. It isn't always possible to abort
correctly, so just fall back on a SCSI bus reset, which will complete the
affected commands with the appropriate result code.

For example, certain Apple (Sony) CD-ROM drives, when the non-existent
LUN 1 is scanned, can't handle the INQUIRY command. The problem is not
detected until the initiator gets a MESSAGE REJECT. Whenever esp_scsi
sees that message, it raises ATN and sends ABORT TASK SET -- but
neglects to complete the failed scmd.

The target then goes into DATA OUT phase (probably bogus), while the ESP
device goes into disconnected mode (surprising, given the bus phase).
The next Transfer Information command from esp_scsi then causes
an Invalid Command interrupt because that command is not valid when in
disconnected mode:

mac_esp: using PDMA for controller 0
mac_esp mac_esp.0: esp0: regs[50f10000:(null)] irq[19]
mac_esp mac_esp.0: esp0: is a ESP236, 16 MHz (ccf=4), SCSI ID 7
scsi host0: esp
scsi 0:0:0:0: Direct-Access     SEAGATE  ST318416N        0010 PQ: 0 ANSI: 3
scsi target0:0:0: Beginning Domain Validation
scsi target0:0:0: asynchronous
scsi target0:0:0: Domain Validation skipping write tests
scsi target0:0:0: Ending Domain Validation
scsi 0:0:3:0: CD-ROM            SONY     CD-ROM CDU-8003A 1.9a PQ: 0 ANSI: 2 CCS
scsi target0:0:3: Beginning Domain Validation
scsi target0:0:3: FAST-5 SCSI 2.0 MB/s ST (500 ns, offset 15)
scsi target0:0:3: Domain Validation skipping write tests
scsi target0:0:3: Ending Domain Validation
scsi host0: unexpected IREG 40
scsi host0: Dumping command log
scsi host0: ent[2] CMD val[c2] sreg[90] seqreg[cc] sreg2[00] ireg[20] ss[01] event[0c]
scsi host0: ent[3] CMD val[00] sreg[91] seqreg[04] sreg2[00] ireg[18] ss[00] event[0c]
scsi host0: ent[4] EVENT val[0d] sreg[91] seqreg[04] sreg2[00] ireg[18] ss[00] event[0c]
scsi host0: ent[5] EVENT val[03] sreg[91] seqreg[04] sreg2[00] ireg[18] ss[00] event[0d]
scsi host0: ent[6] CMD val[90] sreg[91] seqreg[04] sreg2[00] ireg[18] ss[00] event[03]
scsi host0: ent[7] EVENT val[05] sreg[91] seqreg[04] sreg2[00] ireg[18] ss[00] event[03]
scsi host0: ent[8] EVENT val[0d] sreg[93] seqreg[cc] sreg2[00] ireg[10] ss[00] event[05]
scsi host0: ent[9] CMD val[01] sreg[93] seqreg[cc] sreg2[00] ireg[10] ss[00] event[0d]
scsi host0: ent[10] CMD val[11] sreg[93] seqreg[cc] sreg2[00] ireg[10] ss[00] event[0d]
scsi host0: ent[11] EVENT val[0b] sreg[93] seqreg[cc] sreg2[00] ireg[10] ss[00] event[0d]
scsi host0: ent[12] CMD val[12] sreg[97] seqreg[cc] sreg2[00] ireg[08] ss[00] event[0b]
scsi host0: ent[13] EVENT val[0c] sreg[97] seqreg[cc] sreg2[00] ireg[08] ss[00] event[0b]
scsi host0: ent[14] CMD val[44] sreg[90] seqreg[cc] sreg2[00] ireg[20] ss[00] event[0c]
scsi host0: ent[15] CMD val[01] sreg[90] seqreg[cc] sreg2[00] ireg[20] ss[01] event[0c]
scsi host0: ent[16] CMD val[c2] sreg[90] seqreg[cc] sreg2[00] ireg[20] ss[01] event[0c]
scsi host0: ent[17] CMD val[00] sreg[87] seqreg[02] sreg2[00] ireg[18] ss[00] event[0c]
scsi host0: ent[18] EVENT val[0d] sreg[87] seqreg[02] sreg2[00] ireg[18] ss[00] event[0c]
scsi host0: ent[19] EVENT val[06] sreg[87] seqreg[02] sreg2[00] ireg[18] ss[00] event[0d]
scsi host0: ent[20] CMD val[01] sreg[87] seqreg[02] sreg2[00] ireg[18] ss[00] event[06]
scsi host0: ent[21] CMD val[10] sreg[87] seqreg[02] sreg2[00] ireg[18] ss[00] event[06]
scsi host0: ent[22] CMD val[1a] sreg[87] seqreg[ca] sreg2[00] ireg[08] ss[00] event[06]
scsi host0: ent[23] CMD val[12] sreg[87] seqreg[ca] sreg2[00] ireg[08] ss[00] event[06]
scsi host0: ent[24] EVENT val[0d] sreg[87] seqreg[ca] sreg2[00] ireg[08] ss[00] event[06]
scsi host0: ent[25] EVENT val[09] sreg[86] seqreg[ca] sreg2[00] ireg[10] ss[00] event[0d]
scsi host0: ent[26] CMD val[01] sreg[86] seqreg[ca] sreg2[00] ireg[10] ss[00] event[09]
scsi host0: ent[27] CMD val[10] sreg[86] seqreg[ca] sreg2[00] ireg[10] ss[00] event[09]
scsi host0: ent[28] EVENT val[0a] sreg[86] seqreg[ca] sreg2[00] ireg[10] ss[00] event[09]
scsi host0: ent[29] EVENT val[0d] sreg[80] seqreg[ca] sreg2[00] ireg[20] ss[00] event[0a]
scsi host0: ent[30] EVENT val[04] sreg[80] seqreg[ca] sreg2[00] ireg[20] ss[00] event[0d]
scsi host0: ent[31] CMD val[01] sreg[80] seqreg[ca] sreg2[00] ireg[20] ss[00] event[04]
scsi host0: ent[0] CMD val[90] sreg[80] seqreg[ca] sreg2[00] ireg[20] ss[00] event[04]
scsi host0: ent[1] EVENT val[05] sreg[80] seqreg[ca] sreg2[00] ireg[20] ss[00] event[04]
scsi target0:0:3: FAST-5 SCSI 2.0 MB/s ST (500 ns, offset 15)
scsi target0:0:0: asynchronous
sr 0:0:3:0: [sr0] scsi-1 drive
cdrom: Uniform CD-ROM driver Revision: 3.20
sd 0:0:0:0: Attached scsi generic sg0 type 0
sr 0:0:3:0: Attached scsi generic sg1 type 5

This patch resolves this issue because the bus reset causes the INQUIRY
command to fail earlier, and return the appropriate result code.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:55:35 -04:00
Finn Thain
201c37d7bf scsi: esp_scsi: Clean up control flow and dead code
This patch improves readability. There are no functional changes.

Since this touches on a questionable ESP_INTR_DC conditional, add some
commentary to help others who may (as I did) find themselves chasing an
"Invalid Command" error after the device flags this condition.

This cleanup also eliminates a warning from "make W=1":
drivers/scsi/esp_scsi.c: In function 'esp_finish_select':
drivers/scsi/esp_scsi.c:1233:5: warning: variable 'orig_select_state' set but not used [-Wunused-but-set-variable]
  u8 orig_select_state;

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:55:34 -04:00
Finn Thain
7640d91d28 scsi: mac_esp: Fix PIO transfers for MESSAGE IN phase
When in MESSAGE IN phase, the ESP device does not automatically
acknowledge each byte that is transferred by PIO. The mac_esp driver
neglects to explicitly ack them, which causes a timeout during messages
larger than one byte (e.g. tag bytes during reconnect). Fix this with an
ESP_CMD_MOK command after each byte.

The MESSAGE IN phase is also different in that each byte transferred
raises ESP_INTR_FDONE. So don't exit the transfer loop for this interrupt,
for this phase.

That resolves the "Reconnect IRQ2 timeout" error on those Macs which use
PIO transfers instead of PDMA. This patch also improves on the weak tests
for unexpected interrupts and phase changes during PIO transfers.

Tested-by: Stan Johnson <userm57@yahoo.com>
Fixes: 02507a80b3 ("[PATCH] [SCSI] mac_esp: fix PIO mode, take 2")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:55:34 -04:00
Finn Thain
b36c7db977 scsi: mac_esp: Avoid type warning from sparse
Avoid the following warning from "make C=1":

  CHECK   drivers/scsi/mac_esp.c
drivers/scsi/mac_esp.c:357:30: warning: incorrect type in initializer (different address spaces)
drivers/scsi/mac_esp.c:357:30:    expected unsigned char [usertype] *fifo
drivers/scsi/mac_esp.c:357:30:    got void [noderef] <asn:2>*

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:55:34 -04:00
Bhumika Goyal
5f3342d757 arcmsr: add const to bin_attribute structures
Add const to bin_attribute structures as they are only passed to the
functions system_{remove/create}_bin_file. The arguments passed are of
type const, so declare the structures to be const.

Done using Coccinelle.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:40:50 -04:00
Martin Peschke
f32c9e03d4 scsi: zfcp: early returns for traces disabled via level
This patch adds early checks to avoid burning CPU cycles on
the assembly of trace entries which would be skipped anyway.

Introduce a static const variable to keep the trace level to check with
debug_level_enabled() in sync with the actual trace emit with
debug_event(). In order not to refactor the SAN tracing too much,
simply use a define instead.

This change is only for the non / semi hot paths,
while the actual (I/O) hot path was already improved earlier:
zfcp_dbf_scsi() is already guarded by its only caller _zfcp_dbf_scsi()
since commit dcd20e2316 ("[SCSI] zfcp: Only collect SCSI debug data for
matching trace levels").
zfcp_dbf_hba_fsf_res() is already guarded by its only caller
zfcp_dbf_hba_fsf_response() since commit 2e261af84c ("[SCSI] zfcp: Only
collect FSF/HBA debug data for matching trace levels").

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
[maier@linux.vnet.ibm.com: rebase, reword, default level 3 branch prediction]
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:37:03 -04:00
Martin Peschke
b096ef863e scsi: zfcp: clean up unnecessary module_param_named() with no_auto_port_rescan
Improves commit 43f60cbd56 ("[SCSI] zfcp: No automatic port_rescan on
events")

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
[maier@linux.vnet.ibm.com: reword, underscore in description to match sysfs]
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:37:03 -04:00
Martin Peschke
5ec2196060 scsi: zfcp: clean up a member of struct zfcp_qdio that was assigned but never used
v2.6.38 commit a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing
for HBA records.")
dropped trace information previously introduced with
v2.6.27 commit c3baa9a26c ("[SCSI] zfcp: Add information about interrupt
to trace.")
but kept and needlessly assigned a now no longer used struct field.

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
[maier@linux.vnet.ibm.com: reword, added git history]
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:37:02 -04:00
Steffen Maier
46e5ee1f74 scsi: zfcp: clean up no longer existent prototype from zfcp API header
Commit a54ca0f62f ("[SCSI] zfcp: Redesign of the debug tracing for HBA
records.") refactored zfcp_dbf_hba_berr into zfcp_dbf_hba_bit_err
but added the prototype for the latter without removing it for the former.

Suggested-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:37:02 -04:00
Martin Peschke
5f03e98b0f scsi: zfcp: clean up redundant code with fall through in link down SRB switch case
Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
[maier@linux.vnet.ibm.com: re-worded short description for more details]
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:37:01 -04:00
Steffen Maier
5b2fc2a12c scsi: zfcp: fix kernel doc comment typos for struct zfcp_dbf_scsi
Improves commit 250a1352b9 ("[SCSI] zfcp: Redesign of the debug tracing
for SCSI records.")

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:37:01 -04:00
Steffen Maier
9d464fc1b1 scsi: zfcp: use endianness conversions with common FC(P) struct fields
Just to silence sparse. Since zfcp only exists for s390 and
s390 is big endian, this has been working correctly without conversions
and all the new conversions are NOPs so no performance impact.

Nonetheless, use the conversion on the constant expression where possible.

NB: N_Port-IDs have always been handled with hton24 or ntoh24 conversions
because they also convert to / from character array.

Affected common code structs and .fields are:

HOT I/O PATH:
fcp_cmnd .fc_dl
   FCP command: regular SCSI I/O, including DIX case

SEMI-HOT I/O PATH:
fcp_cmnd .fc_dl
   recovery FCP command: task management function (LUN / target reset)
fcp_resp_ext
   FCP response having FCP_SNS_LEN_VAL with .fr_rsp_len .fr_sns_len
   FCP response having FCP_RESID_UNDER with .fr_resid

RECOVERY / DISCOVERY PATHS:
fc_ct_hdr .ct_cmd .ct_mr_size
   zfcp auto port scan [GPN_FT] with fc_gpn_ft_resp.fp_wwpn,
   recovery for returned port [GID_PN] with fc_ns_gid_pn.fn_wwpn,
   get symbolic port name [GSPN],
   register symbolic port name [RSPN] (NPIV only).
fc_els_rscn .rscn_plen
   incoming ELS (RSCN).
fc_els_flogi .fl_wwpn .fl_wwnn
   incoming ELS (PLOGI),
   port open response with .fl_csp.sp_bb_data .fl_cssp[0..3].cp_class,
   FCP channel physical port,
   point-to-point peer (P2P only).
fc_els_logo .fl_n_port_wwn
   incoming ELS (LOGO).
fc_els_adisc .adisc_wwnn .adisc_wwpn
   path test after RSCN for gone target port.

Since v4.10 commit 05de97003c ("linux/types.h: enable endian checks for
all sparse builds"), below sparse endianness reports appear by default.
Previously, one needed to pass argument CF="-D__CHECK_ENDIAN__" to make
as in: $ make C=1 CF="-D__CHECK_ENDIAN__" M=drivers/s390/scsi.

Silenced sparse warnings and one error:

$ make C=1 M=drivers/s390/scsi
...
  CHECK   drivers/s390/scsi/zfcp_dbf.c
drivers/s390/scsi/zfcp_dbf.c:463:22: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_dbf.c:476:28: warning: restricted __be16 degrades to integer
  CC      drivers/s390/scsi/zfcp_dbf.o
...
  CHECK   drivers/s390/scsi/zfcp_fc.c
drivers/s390/scsi/zfcp_fc.c:263:26: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:299:41: warning: incorrect type in argument 2 (different base types)
drivers/s390/scsi/zfcp_fc.c:299:41:    expected unsigned long long [unsigned] [usertype] wwpn
drivers/s390/scsi/zfcp_fc.c:299:41:    got restricted __be64 [usertype] fl_wwpn
drivers/s390/scsi/zfcp_fc.c:309:40: warning: incorrect type in argument 2 (different base types)
drivers/s390/scsi/zfcp_fc.c:309:40:    expected unsigned long long [unsigned] [usertype] wwpn
drivers/s390/scsi/zfcp_fc.c:309:40:    got restricted __be64 [usertype] fl_n_port_wwn
drivers/s390/scsi/zfcp_fc.c:338:31: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:355:24: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:355:24:    expected restricted __be16 [usertype] ct_cmd
drivers/s390/scsi/zfcp_fc.c:355:24:    got unsigned short [unsigned] [usertype] cmd
drivers/s390/scsi/zfcp_fc.c:356:28: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:356:28:    expected restricted __be16 [usertype] ct_mr_size
drivers/s390/scsi/zfcp_fc.c:356:28:    got int
drivers/s390/scsi/zfcp_fc.c:379:36: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:379:36:    expected restricted __be64 [usertype] fn_wwpn
drivers/s390/scsi/zfcp_fc.c:379:36:    got unsigned long long [unsigned] [usertype] wwpn
drivers/s390/scsi/zfcp_fc.c:463:18: warning: restricted __be64 degrades to integer
drivers/s390/scsi/zfcp_fc.c:465:17: warning: cast from restricted __be64
drivers/s390/scsi/zfcp_fc.c:473:20: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:473:20:    expected unsigned long long [unsigned] [usertype] wwnn
drivers/s390/scsi/zfcp_fc.c:473:20:    got restricted __be64 [usertype] fl_wwnn
drivers/s390/scsi/zfcp_fc.c:474:29: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:474:29:    expected unsigned int [unsigned] [usertype] maxframe_size
drivers/s390/scsi/zfcp_fc.c:474:29:    got restricted __be16 [usertype] sp_bb_data
drivers/s390/scsi/zfcp_fc.c:476:30: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:478:30: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:480:30: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:482:30: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:500:28: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:500:28:    expected unsigned long long [unsigned] [usertype] wwnn
drivers/s390/scsi/zfcp_fc.c:500:28:    got restricted __be64 [usertype] adisc_wwnn
drivers/s390/scsi/zfcp_fc.c:502:38: warning: restricted __be64 degrades to integer
drivers/s390/scsi/zfcp_fc.c:541:40: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:541:40:    expected restricted __be64 [usertype] adisc_wwpn
drivers/s390/scsi/zfcp_fc.c:541:40:    got unsigned long long [unsigned] [usertype] port_name
drivers/s390/scsi/zfcp_fc.c:542:40: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fc.c:542:40:    expected restricted __be64 [usertype] adisc_wwnn
drivers/s390/scsi/zfcp_fc.c:542:40:    got unsigned long long [unsigned] [usertype] node_name
drivers/s390/scsi/zfcp_fc.c:669:16: warning: restricted __be16 degrades to integer
drivers/s390/scsi/zfcp_fc.c:696:24: warning: restricted __be64 degrades to integer
drivers/s390/scsi/zfcp_fc.c:699:54: warning: incorrect type in argument 2 (different base types)
drivers/s390/scsi/zfcp_fc.c:699:54:    expected unsigned long long [unsigned] [usertype] <noident>
drivers/s390/scsi/zfcp_fc.c:699:54:    got restricted __be64 [usertype] fp_wwpn
  CC      drivers/s390/scsi/zfcp_fc.o
  CHECK   drivers/s390/scsi/zfcp_fsf.c
drivers/s390/scsi/zfcp_fsf.c:479:34: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fsf.c:479:34:    expected unsigned long long [unsigned] [usertype] port_name
drivers/s390/scsi/zfcp_fsf.c:479:34:    got restricted __be64 [usertype] fl_wwpn
drivers/s390/scsi/zfcp_fsf.c:480:34: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fsf.c:480:34:    expected unsigned long long [unsigned] [usertype] node_name
drivers/s390/scsi/zfcp_fsf.c:480:34:    got restricted __be64 [usertype] fl_wwnn
drivers/s390/scsi/zfcp_fsf.c:506:36: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fsf.c:506:36:    expected unsigned long long [unsigned] [usertype] peer_wwpn
drivers/s390/scsi/zfcp_fsf.c:506:36:    got restricted __be64 [usertype] fl_wwpn
drivers/s390/scsi/zfcp_fsf.c:507:36: warning: incorrect type in assignment (different base types)
drivers/s390/scsi/zfcp_fsf.c:507:36:    expected unsigned long long [unsigned] [usertype] peer_wwnn
drivers/s390/scsi/zfcp_fsf.c:507:36:    got restricted __be64 [usertype] fl_wwnn
drivers/s390/scsi/zfcp_fc.h:269:46: warning: restricted __be32 degrades to integer
drivers/s390/scsi/zfcp_fc.h:270:29: error: incompatible types in comparison expression (different base types)

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:37:00 -04:00
Steffen Maier
df00d7b8d5 scsi: zfcp: use common code fcp_cmnd and fcp_resp with union in fsf_qtcb_bottom_io
This eases crash dump analysis by automatically dissecting these
protocol headers at least somewhat rather than getting a string
interpretation of large unstructured character array buffer fields.

Also, we can get rid of some unnecessary and error-prone type casts.

This change is possible since v2.6.33 commit 4318e08c84
("[SCSI] zfcp: Update FCP protocol related code").

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:37:00 -04:00
Steffen Maier
394134fd9f scsi: zfcp: clarify that we don't need "link" test on failed open port
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:36:59 -04:00
Steffen Maier
ab8ab4be78 scsi: zfcp: more fitting constant for fc_ct_hdr.ct_reason on port scan response
v2.6.33 commit dbf5dfe9db ("[SCSI] zfcp: Use common code definitions for
FC CT structs") replaced own definitions with common code definitions.
While FC_BA_RJT_UNABLE happens to be defined with the same value 9 as
FC_FS_RJT_UNABL and thus also works, here we should use the latter from
fc_gs.h.
See also its use in libfc's fc_disc_gpn_ft_resp().

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
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>
2017-08-10 19:36:59 -04:00
Steffen Maier
5d4a3d0a2f scsi: zfcp: trace high part of "new" 64 bit SCSI LUN
Complements debugging aspects of the otherwise functionally complete
v3.17 commit 9cb78c16f5 ("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: 9cb78c16f5 ("scsi: use 64-bit LUNs")
Cc: <stable@vger.kernel.org> #3.17+
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>
2017-08-10 19:36:58 -04:00
Steffen Maier
fdb7cee3b9 scsi: zfcp: trace HBA FSF response by default on dismiss or timedout late response
At the default trace level, we only trace unsuccessful events including
FSF responses.

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

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

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

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

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

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

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

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

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

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

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

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 8a36e4532e ("[SCSI] zfcp: enhancement of zfcp debug features")
Fixes: 2e261af84c ("[SCSI] zfcp: Only collect FSF/HBA debug data for matching trace levels")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:57 -04:00
Steffen Maier
12c3e5754c scsi: zfcp: fix payload with full FCP_RSP IU in SCSI trace records
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 aceeffbb59
("zfcp: trace full payload of all SAN records (req,resp,iels)").
This does not cause any additional trace records wasting memory.

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

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

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

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

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

New example trace records with this fix:

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

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

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 250a1352b9 ("[SCSI] zfcp: Redesign of the debug tracing for SCSI records.")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:57 -04:00
Steffen Maier
1a5d999ebf scsi: zfcp: fix missing trace records for early returns in TMF eh handlers
For problem determination we need to see that we were in scsi_eh
as well as whether and why we were successful or not.

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

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

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

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: a1dbfddd02 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh")
Fixes: 63caf367e1 ("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:56 -04:00
Steffen Maier
9fe5d2b2fd scsi: zfcp: fix passing fsf_req to SCSI trace on TMF to correlate with HBA
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 8a36e4532e ("[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: 8a36e4532e ("[SCSI] zfcp: enhancement of zfcp debug features")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:56 -04:00
Steffen Maier
975171b446 scsi: zfcp: fix capping of unsuccessful GPN_FT SAN response trace records
v4.9 commit aceeffbb59 ("zfcp: trace full payload of all SAN records
(req,resp,iels)") fixed trace data loss of 2.6.38 commit 2c55b750a8
("[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: aceeffbb59 ("zfcp: trace full payload of all SAN records (req,resp,iels)")
Fixes: 2c55b750a8 ("[SCSI] zfcp: Redesign of the debug tracing for SAN records.")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:55 -04:00
Benjamin Block
a099b7b1fc scsi: zfcp: add handling for FCP_RESID_OVER to the fcp ingress path
Up until now zfcp would just ignore the FCP_RESID_OVER flag in the FCP
response IU. When this flag is set, it is possible, in regards to the
FCP standard, that the storage-server processes the command normally, up
to the point where data is missing and simply ignores those.

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

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

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

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

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

Reported-by: Luke M. Hopkins <lmhopkin@us.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: 553448f6c4 ("[SCSI] zfcp: Message cleanup")
Fixes: ea127f975424 ("[PATCH] s390 (7/7): zfcp host adapter.") (tglx/history.git)
Cc: <stable@vger.kernel.org> #2.6.33+
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:55 -04:00
Steffen Maier
71b8e45da5 scsi: zfcp: fix queuecommand for scsi_eh commands when DIX enabled
Since commit db007fc5e2 ("[SCSI] Command protection operation"),
scsi_eh_prep_cmnd() saves scmd->prot_op and temporarily resets it to
SCSI_PROT_NORMAL.
Other FCP LLDDs such as qla2xxx and lpfc shield their queuecommand()
to only access any of scsi_prot_sg...() if
(scsi_get_prot_op(cmd) != SCSI_PROT_NORMAL).

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

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

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

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

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes: ef3eb71d8b ("[SCSI] zfcp: Introduce experimental support for DIF/DIX")
Cc: <stable@vger.kernel.org> #2.6.36+
Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:54 -04:00
Benjamin Block
5156934bd6 scsi: zfcp: convert bool-definitions to use 'true' instead of '1'
Better form and cleans remaining warnings.

Found with scripts/coccinelle/misc/boolinit.cocci.

Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:54 -04:00
Corentin Labbe
16d75e6503 scsi: zfcp: Remove unneeded linux/miscdevice.h include
drivers/s390/scsi/zfcp_aux.c does not contain any miscdevice so the
inclusion of linux/miscdevice.h is unnecessary.

[maier@linux.vnet.ibm.com: just for the records, this is in fact a
 minor missing code cleanup of the following older "feature"
 which also dropped the only former use of a misc device in zfcp:
 commit 663e0890e3 ("[SCSI] zfcp: remove access control tables
				    interface")
 commit b5dc3c4800 ("[SCSI] zfcp: remove access control tables
				    interface (keep sysfs files)")
 commit 1b33ef2394 ("zfcp: remove access control tables interface
			     (port leftovers)")]

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:53 -04:00
Lukáš Korenčik
bc46427e80 scsi: zfcp: use setup_timer instead of init_timer
Use initialization with setup_timer function instead of using
init_timer function and data fields. It improves readability.

Signed-off-by: Lukáš Korenčik <xkorenc1@fi.muni.cz>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:53 -04:00
LABBE Corentin
7d91869c73 scsi: zfcp: replace zfcp_qdio_sbale_count by sg_nents
The zfcp_qdio_sbale_count function do the same work than sg_nents().
So replace it by sg_nents() for removing duplicate code.

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:52 -04:00
Varun Prakash
4737c5a067 scsi: libcxgbi: use ndev->ifindex to find route
If cxgbi_ep_connect() is called with valid shost then find associated
ndev and use ndev->ifindex to find route.

Signed-off-by: Varun Prakash <varun@chelsio.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:52 -04:00
Christophe JAILLET
a5dd7efd35 scsi: mpt3sas: Fix memory allocation failure test in 'mpt3sas_base_attach()'
In the lines above this test, 8 'kzalloc' are performed, but only 7
results are tested.

Add the missing one (i.e. '!ioc->port_enable_cmds.reply').

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:51 -04:00
Michał Mirosław
2ae203fa28 scsi: aic7xxx: regenerate firmware files
Regenerate firmware files to make cleaner base for following fix.
This removes some unused definitions and reorders some #defines, but
the code remains the same.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-10 19:36:51 -04:00
Rafael J. Wysocki
23d5855f47 PM / s2idle: Rename platform operations structure
Rename struct platform_freeze_ops to platform_s2idle_ops to make it
clear that the callbacks in it are used during suspend-to-idle
suspend/resume transitions and rename the related functions,
variables and so on accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-11 01:29:56 +02:00
Rafael J. Wysocki
28ba086ed3 PM / s2idle: Rename ->enter_freeze to ->enter_s2idle
Rename the ->enter_freeze cpuidle driver callback to ->enter_s2idle
to make it clear that it is used for entering suspend-to-idle and
rename the related functions, variables and so on accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-11 01:29:56 +02:00
Rafael J. Wysocki
f02f4f9d82 PM / s2idle: Rename freeze_state enum and related items
Rename the freeze_state enum representing the suspend-to-idle state
machine states to s2idle_states and rename the related variables and
functions accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-11 01:29:55 +02:00
Rafael J. Wysocki
690cbb90a7 PM / s2idle: Rename PM_SUSPEND_FREEZE to PM_SUSPEND_TO_IDLE
To make it clear that the symbol in question refers to
suspend-to-idle, rename it from PM_SUSPEND_FREEZE to
PM_SUSPEND_TO_IDLE.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-11 01:29:55 +02:00
Doug Smythies
8e2f3bce05 cpufreq: x86: Disable interrupts during MSRs reading
According to Intel 64 and IA-32 Architectures SDM, Volume 3,
Chapter 14.2, "Software needs to exercise care to avoid delays
between the two RDMSRs (for example interrupts)".

So, disable interrupts during reading MSRs IA32_APERF and IA32_MPERF.

See also: commit 4ab60c3f32 (cpufreq: intel_pstate: Disable
interrupts during MSRs reading).

Signed-off-by: Doug Smythies <dsmythies@telus.net>
Reviewed-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-11 01:27:41 +02:00
Doug Smythies
c587c79f90 cpufreq: intel_pstate: report correct CPU frequencies during trace
The intel_pstate CPU frequency scaling driver has always
calculated CPU frequency incorrectly.  Recent changes have
eliminted most of the issues, however the frequency reported
in the trace buffer, if used, is incorrect.

It remains desireable that cpu->pstate.scaling still be a nice
round number for things such as when setting max and min frequencies.
So the proposal is to just fix the reported frequency in the trace data.

Fixes what remains of [1].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=96521 # [1]
Signed-off-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-11 01:25:53 +02:00
Linus Torvalds
27df704d43 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "21 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (21 commits)
  userfaultfd: replace ENOSPC with ESRCH in case mm has gone during copy/zeropage
  zram: rework copy of compressor name in comp_algorithm_store()
  rmap: do not call mmu_notifier_invalidate_page() under ptl
  mm: fix list corruptions on shmem shrinklist
  mm/balloon_compaction.c: don't zero ballooned pages
  MAINTAINERS: copy virtio on balloon_compaction.c
  mm: fix KSM data corruption
  mm: fix MADV_[FREE|DONTNEED] TLB flush miss problem
  mm: make tlb_flush_pending global
  mm: refactor TLB gathering API
  Revert "mm: numa: defer TLB flush for THP migration as long as possible"
  mm: migrate: fix barriers around tlb_flush_pending
  mm: migrate: prevent racy access to tlb_flush_pending
  fault-inject: fix wrong should_fail() decision in task context
  test_kmod: fix small memory leak on filesystem tests
  test_kmod: fix the lock in register_test_dev_kmod()
  test_kmod: fix bug which allows negative values on two config options
  test_kmod: fix spelling mistake: "EMTPY" -> "EMPTY"
  userfaultfd: hugetlbfs: remove superfluous page unlock in VM_SHARED case
  mm: ratelimit PFNs busy info message
  ...
2017-08-10 16:20:52 -07:00
Mike Rapoport
e86b298beb userfaultfd: replace ENOSPC with ESRCH in case mm has gone during copy/zeropage
When the process exit races with outstanding mcopy_atomic, it would be
better to return ESRCH error.  When such race occurs the process and
it's mm are going away and returning "no such process" to the uffd
monitor seems better fit than ENOSPC.

Link: http://lkml.kernel.org/r/1502111545-32305-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Matthias Kaehlcke
f357e345ee zram: rework copy of compressor name in comp_algorithm_store()
comp_algorithm_store() passes the size of the source buffer to strlcpy()
instead of the destination buffer size.  Make it explicit that the two
buffers have the same size and use strcpy() instead of strlcpy().  The
latter can be done safely since the function ensures that the string in
the source buffer is terminated.

Link: http://lkml.kernel.org/r/20170803163350.45245-1-mka@chromium.org
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Kirill A. Shutemov
aac2fea94f rmap: do not call mmu_notifier_invalidate_page() under ptl
MMU notifiers can sleep, but in page_mkclean_one() we call
mmu_notifier_invalidate_page() under page table lock.

Let's instead use mmu_notifier_invalidate_range() outside
page_vma_mapped_walk() loop.

[jglisse@redhat.com: try_to_unmap_one() do not call mmu_notifier under ptl]
  Link: http://lkml.kernel.org/r/20170809204333.27485-1-jglisse@redhat.com
Link: http://lkml.kernel.org/r/20170804134928.l4klfcnqatni7vsc@black.fi.intel.com
Fixes: c7ab0d2fdc ("mm: convert try_to_unmap_one() to use page_vma_mapped_walk()")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reported-by: axie <axie@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Writer, Tim" <Tim.Writer@amd.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Cong Wang
d041353dc9 mm: fix list corruptions on shmem shrinklist
We saw many list corruption warnings on shmem shrinklist:

  WARNING: CPU: 18 PID: 177 at lib/list_debug.c:59 __list_del_entry+0x9e/0xc0
  list_del corruption. prev->next should be ffff9ae5694b82d8, but was ffff9ae5699ba960
  Modules linked in: intel_rapl sb_edac edac_core x86_pkg_temp_thermal coretemp iTCO_wdt iTCO_vendor_support crct10dif_pclmul crc32_pclmul ghash_clmulni_intel raid0 dcdbas shpchp wmi hed i2c_i801 ioatdma lpc_ich i2c_smbus acpi_cpufreq tcp_diag inet_diag sch_fq_codel ipmi_si ipmi_devintf ipmi_msghandler igb ptp crc32c_intel pps_core i2c_algo_bit i2c_core dca ipv6 crc_ccitt
  CPU: 18 PID: 177 Comm: kswapd1 Not tainted 4.9.34-t3.el7.twitter.x86_64 #1
  Hardware name: Dell Inc. PowerEdge C6220/0W6W6G, BIOS 2.2.3 11/07/2013
  Call Trace:
    dump_stack+0x4d/0x66
    __warn+0xcb/0xf0
    warn_slowpath_fmt+0x4f/0x60
    __list_del_entry+0x9e/0xc0
    shmem_unused_huge_shrink+0xfa/0x2e0
    shmem_unused_huge_scan+0x20/0x30
    super_cache_scan+0x193/0x1a0
    shrink_slab.part.41+0x1e3/0x3f0
    shrink_slab+0x29/0x30
    shrink_node+0xf9/0x2f0
    kswapd+0x2d8/0x6c0
    kthread+0xd7/0xf0
    ret_from_fork+0x22/0x30

  WARNING: CPU: 23 PID: 639 at lib/list_debug.c:33 __list_add+0x89/0xb0
  list_add corruption. prev->next should be next (ffff9ae5699ba960), but was ffff9ae5694b82d8. (prev=ffff9ae5694b82d8).
  Modules linked in: intel_rapl sb_edac edac_core x86_pkg_temp_thermal coretemp iTCO_wdt iTCO_vendor_support crct10dif_pclmul crc32_pclmul ghash_clmulni_intel raid0 dcdbas shpchp wmi hed i2c_i801 ioatdma lpc_ich i2c_smbus acpi_cpufreq tcp_diag inet_diag sch_fq_codel ipmi_si ipmi_devintf ipmi_msghandler igb ptp crc32c_intel pps_core i2c_algo_bit i2c_core dca ipv6 crc_ccitt
  CPU: 23 PID: 639 Comm: systemd-udevd Tainted: G        W       4.9.34-t3.el7.twitter.x86_64 #1
  Hardware name: Dell Inc. PowerEdge C6220/0W6W6G, BIOS 2.2.3 11/07/2013
  Call Trace:
    dump_stack+0x4d/0x66
    __warn+0xcb/0xf0
    warn_slowpath_fmt+0x4f/0x60
    __list_add+0x89/0xb0
    shmem_setattr+0x204/0x230
    notify_change+0x2ef/0x440
    do_truncate+0x5d/0x90
    path_openat+0x331/0x1190
    do_filp_open+0x7e/0xe0
    do_sys_open+0x123/0x200
    SyS_open+0x1e/0x20
    do_syscall_64+0x61/0x170
    entry_SYSCALL64_slow_path+0x25/0x25

The problem is that shmem_unused_huge_shrink() moves entries from the
global sbinfo->shrinklist to its local lists and then releases the
spinlock.  However, a parallel shmem_setattr() could access one of these
entries directly and add it back to the global shrinklist if it is
removed, with the spinlock held.

The logic itself looks solid since an entry could be either in a local
list or the global list, otherwise it is removed from one of them by
list_del_init().  So probably the race condition is that, one CPU is in
the middle of INIT_LIST_HEAD() but the other CPU calls list_empty()
which returns true too early then the following list_add_tail() sees a
corrupted entry.

list_empty_careful() is designed to fix this situation.

[akpm@linux-foundation.org: add comments]
Link: http://lkml.kernel.org/r/20170803054630.18775-1-xiyou.wangcong@gmail.com
Fixes: 779750d20b ("shmem: split huge pages beyond i_size under memory pressure")
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Wei Wang
af54aed94b mm/balloon_compaction.c: don't zero ballooned pages
Revert commit bb01b64cfa ("mm/balloon_compaction.c: enqueue zero page
to balloon device")'

Zeroing ballon pages is rather time consuming, especially when a lot of
pages are in flight. E.g. 7GB worth of ballooned memory takes 2.8s with
__GFP_ZERO while it takes ~491ms without it.

The original commit argued that zeroing will help ksmd to merge these
pages on the host but this argument is assuming that the host actually
marks balloon pages for ksm which is not universally true.  So we pay
performance penalty for something that even might not be used in the end
which is wrong.  The host can zero out pages on its own when there is a
need.

[mhocko@kernel.org: new changelog text]
Link: http://lkml.kernel.org/r/1501761557-9758-1-git-send-email-wei.w.wang@intel.com
Fixes: bb01b64cfa ("mm/balloon_compaction.c: enqueue zero page to balloon device")
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: zhenwei.pi <zhenwei.pi@youruncloud.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Michael S. Tsirkin
c0a6a5ae6b MAINTAINERS: copy virtio on balloon_compaction.c
Changes to mm/balloon_compaction.c can easily break virtio, and virtio
is the only user of that interface.  Add a line to MAINTAINERS so
whoever changes that file remembers to copy us.

Link: http://lkml.kernel.org/r/1501764010-24456-1-git-send-email-mst@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Minchan Kim
b3a81d0841 mm: fix KSM data corruption
Nadav reported KSM can corrupt the user data by the TLB batching
race[1].  That means data user written can be lost.

Quote from Nadav Amit:
 "For this race we need 4 CPUs:

  CPU0: Caches a writable and dirty PTE entry, and uses the stale value
  for write later.

  CPU1: Runs madvise_free on the range that includes the PTE. It would
  clear the dirty-bit. It batches TLB flushes.

  CPU2: Writes 4 to /proc/PID/clear_refs , clearing the PTEs soft-dirty.
  We care about the fact that it clears the PTE write-bit, and of
  course, batches TLB flushes.

  CPU3: Runs KSM. Our purpose is to pass the following test in
  write_protect_page():

	if (pte_write(*pvmw.pte) || pte_dirty(*pvmw.pte) ||
	    (pte_protnone(*pvmw.pte) && pte_savedwrite(*pvmw.pte)))

  Since it will avoid TLB flush. And we want to do it while the PTE is
  stale. Later, and before replacing the page, we would be able to
  change the page.

  Note that all the operations the CPU1-3 perform canhappen in parallel
  since they only acquire mmap_sem for read.

  We start with two identical pages. Everything below regards the same
  page/PTE.

  CPU0        CPU1        CPU2        CPU3
  ----        ----        ----        ----
  Write the same
  value on page

  [cache PTE as
   dirty in TLB]

              MADV_FREE
              pte_mkclean()

                          4 > clear_refs
                          pte_wrprotect()

                                      write_protect_page()
                                      [ success, no flush ]

                                      pages_indentical()
                                      [ ok ]

  Write to page
  different value

  [Ok, using stale
   PTE]

                                      replace_page()

  Later, CPU1, CPU2 and CPU3 would flush the TLB, but that is too late.
  CPU0 already wrote on the page, but KSM ignored this write, and it got
  lost"

In above scenario, MADV_FREE is fixed by changing TLB batching API
including [set|clear]_tlb_flush_pending.  Remained thing is soft-dirty
part.

This patch changes soft-dirty uses TLB batching API instead of
flush_tlb_mm and KSM checks pending TLB flush by using
mm_tlb_flush_pending so that it will flush TLB to avoid data lost if
there are other parallel threads pending TLB flush.

[1] http://lkml.kernel.org/r/BD3A0EBE-ECF4-41D4-87FA-C755EA9AB6BD@gmail.com

Link: http://lkml.kernel.org/r/20170802000818.4760-8-namit@vmware.com
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Reported-by: Nadav Amit <namit@vmware.com>
Tested-by: Nadav Amit <namit@vmware.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Minchan Kim
99baac21e4 mm: fix MADV_[FREE|DONTNEED] TLB flush miss problem
Nadav reported parallel MADV_DONTNEED on same range has a stale TLB
problem and Mel fixed it[1] and found same problem on MADV_FREE[2].

Quote from Mel Gorman:
 "The race in question is CPU 0 running madv_free and updating some PTEs
  while CPU 1 is also running madv_free and looking at the same PTEs.
  CPU 1 may have writable TLB entries for a page but fail the pte_dirty
  check (because CPU 0 has updated it already) and potentially fail to
  flush.

  Hence, when madv_free on CPU 1 returns, there are still potentially
  writable TLB entries and the underlying PTE is still present so that a
  subsequent write does not necessarily propagate the dirty bit to the
  underlying PTE any more. Reclaim at some unknown time at the future
  may then see that the PTE is still clean and discard the page even
  though a write has happened in the meantime. I think this is possible
  but I could have missed some protection in madv_free that prevents it
  happening."

This patch aims for solving both problems all at once and is ready for
other problem with KSM, MADV_FREE and soft-dirty story[3].

TLB batch API(tlb_[gather|finish]_mmu] uses [inc|dec]_tlb_flush_pending
and mmu_tlb_flush_pending so that when tlb_finish_mmu is called, we can
catch there are parallel threads going on.  In that case, forcefully,
flush TLB to prevent for user to access memory via stale TLB entry
although it fail to gather page table entry.

I confirmed this patch works with [4] test program Nadav gave so this
patch supersedes "mm: Always flush VMA ranges affected by zap_page_range
v2" in current mmotm.

NOTE:

This patch modifies arch-specific TLB gathering interface(x86, ia64,
s390, sh, um).  It seems most of architecture are straightforward but
s390 need to be careful because tlb_flush_mmu works only if
mm->context.flush_mm is set to non-zero which happens only a pte entry
really is cleared by ptep_get_and_clear and friends.  However, this
problem never changes the pte entries but need to flush to prevent
memory access from stale tlb.

[1] http://lkml.kernel.org/r/20170725101230.5v7gvnjmcnkzzql3@techsingularity.net
[2] http://lkml.kernel.org/r/20170725100722.2dxnmgypmwnrfawp@suse.de
[3] http://lkml.kernel.org/r/BD3A0EBE-ECF4-41D4-87FA-C755EA9AB6BD@gmail.com
[4] https://patchwork.kernel.org/patch/9861621/

[minchan@kernel.org: decrease tlb flush pending count in tlb_finish_mmu]
  Link: http://lkml.kernel.org/r/20170808080821.GA31730@bbox
Link: http://lkml.kernel.org/r/20170802000818.4760-7-namit@vmware.com
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Reported-by: Nadav Amit <namit@vmware.com>
Reported-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Minchan Kim
0a2dd266dd mm: make tlb_flush_pending global
Currently, tlb_flush_pending is used only for CONFIG_[NUMA_BALANCING|
COMPACTION] but upcoming patches to solve subtle TLB flush batching
problem will use it regardless of compaction/NUMA so this patch doesn't
remove the dependency.

[akpm@linux-foundation.org: remove more ifdefs from world's ugliest printk statement]
Link: http://lkml.kernel.org/r/20170802000818.4760-6-namit@vmware.com
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Minchan Kim
56236a5955 mm: refactor TLB gathering API
This patch is a preparatory patch for solving race problems caused by
TLB batch.  For that, we will increase/decrease TLB flush pending count
of mm_struct whenever tlb_[gather|finish]_mmu is called.

Before making it simple, this patch separates architecture specific part
and rename it to arch_tlb_[gather|finish]_mmu and generic part just
calls it.

It shouldn't change any behavior.

Link: http://lkml.kernel.org/r/20170802000818.4760-5-namit@vmware.com
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Nadav Amit
a9b802500e Revert "mm: numa: defer TLB flush for THP migration as long as possible"
While deferring TLB flushes is a good practice, the reverted patch
caused pending TLB flushes to be checked while the page-table lock is
not taken.  As a result, in architectures with weak memory model (PPC),
Linux may miss a memory-barrier, miss the fact TLB flushes are pending,
and cause (in theory) a memory corruption.

Since the alternative of using smp_mb__after_unlock_lock() was
considered a bit open-coded, and the performance impact is expected to
be small, the previous patch is reverted.

This reverts b0943d61b8 ("mm: numa: defer TLB flush for THP migration
as long as possible").

Link: http://lkml.kernel.org/r/20170802000818.4760-4-namit@vmware.com
Signed-off-by: Nadav Amit <namit@vmware.com>
Suggested-by: Mel Gorman <mgorman@suse.de>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00
Nadav Amit
0a2c40487f mm: migrate: fix barriers around tlb_flush_pending
Reading tlb_flush_pending while the page-table lock is taken does not
require a barrier, since the lock/unlock already acts as a barrier.
Removing the barrier in mm_tlb_flush_pending() to address this issue.

However, migrate_misplaced_transhuge_page() calls mm_tlb_flush_pending()
while the page-table lock is already released, which may present a
problem on architectures with weak memory model (PPC).  To deal with
this case, a new parameter is added to mm_tlb_flush_pending() to
indicate if it is read without the page-table lock taken, and calling
smp_mb__after_unlock_lock() in this case.

Link: http://lkml.kernel.org/r/20170802000818.4760-3-namit@vmware.com
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 15:54:07 -07:00