linux-stable.git/include/scsi, branch v4.4.166

scsi: Add STARGET_CREATED_REMOVE state to scsi_target_state

2018-11-10T15:41:37+00:00

[ Upstream commit f9279c968c257ee39b0d7bd2571a4d231a67bcc1 ]

The addition of the STARGET_REMOVE state had the side effect of
introducing a race condition that can cause a crash.

scsi_target_reap_ref_release() checks the starget->state to
see if it still in STARGET_CREATED, and if so, skips calling
transport_remove_device() and device_del(), because the starget->state
is only set to STARGET_RUNNING after scsi_target_add() has called
device_add() and transport_add_device().

However, if an rport loss occurs while a target is being scanned,
it can happen that scsi_remove_target() will be called while the
starget is still in the STARGET_CREATED state.  In this case, the
starget->state will be set to STARGET_REMOVE, and as a result,
scsi_target_reap_ref_release() will take the wrong path.  The end
result is a panic:

[ 1255.356653] Oops: 0000 [#1] SMP
[ 1255.360154] Modules linked in: x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel ghash_clmulni_i
[ 1255.393234] CPU: 5 PID: 149 Comm: kworker/u96:4 Tainted: G        W       4.11.0+ #8
[ 1255.401879] Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013
[ 1255.410327] Workqueue: scsi_wq_6 fc_scsi_scan_rport [scsi_transport_fc]
[ 1255.417720] task: ffff88060ca8c8c0 task.stack: ffffc900048a8000
[ 1255.424331] RIP: 0010:kernfs_find_ns+0x13/0xc0
[ 1255.429287] RSP: 0018:ffffc900048abbf0 EFLAGS: 00010246
[ 1255.435123] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 1255.443083] RDX: 0000000000000000 RSI: ffffffff8188d659 RDI: 0000000000000000
[ 1255.451043] RBP: ffffc900048abc10 R08: 0000000000000000 R09: 0000012433fe0025
[ 1255.459005] R10: 0000000025e5a4b5 R11: 0000000025e5a4b5 R12: ffffffff8188d659
[ 1255.466972] R13: 0000000000000000 R14: ffff8805f55e5088 R15: 0000000000000000
[ 1255.474931] FS:  0000000000000000(0000) GS:ffff880616b40000(0000) knlGS:0000000000000000
[ 1255.483959] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1255.490370] CR2: 0000000000000068 CR3: 0000000001c09000 CR4: 00000000000406e0
[ 1255.498332] Call Trace:
[ 1255.501058]  kernfs_find_and_get_ns+0x31/0x60
[ 1255.505916]  sysfs_unmerge_group+0x1d/0x60
[ 1255.510498]  dpm_sysfs_remove+0x22/0x60
[ 1255.514783]  device_del+0xf4/0x2e0
[ 1255.518577]  ? device_remove_file+0x19/0x20
[ 1255.523241]  attribute_container_class_device_del+0x1a/0x20
[ 1255.529457]  transport_remove_classdev+0x4e/0x60
[ 1255.534607]  ? transport_add_class_device+0x40/0x40
[ 1255.540046]  attribute_container_device_trigger+0xb0/0xc0
[ 1255.546069]  transport_remove_device+0x15/0x20
[ 1255.551025]  scsi_target_reap_ref_release+0x25/0x40
[ 1255.556467]  scsi_target_reap+0x2e/0x40
[ 1255.560744]  __scsi_scan_target+0xaa/0x5b0
[ 1255.565312]  scsi_scan_target+0xec/0x100
[ 1255.569689]  fc_scsi_scan_rport+0xb1/0xc0 [scsi_transport_fc]
[ 1255.576099]  process_one_work+0x14b/0x390
[ 1255.580569]  worker_thread+0x4b/0x390
[ 1255.584651]  kthread+0x109/0x140
[ 1255.588251]  ? rescuer_thread+0x330/0x330
[ 1255.592730]  ? kthread_park+0x60/0x60
[ 1255.596815]  ret_from_fork+0x29/0x40
[ 1255.600801] Code: 24 08 48 83 42 40 01 5b 41 5c 5d c3 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90
[ 1255.621876] RIP: kernfs_find_ns+0x13/0xc0 RSP: ffffc900048abbf0
[ 1255.628479] CR2: 0000000000000068
[ 1255.632756] ---[ end trace 34a69ba0477d036f ]---

Fix this by adding another scsi_target state STARGET_CREATED_REMOVE
to distinguish this case.

Fixes: f05795d3d771 ("scsi: Add intermediate STARGET_REMOVE state to scsi_target_state")
Reported-by: David Jeffery 
Signed-off-by: Ewan D. Milne 
Cc: 
Reviewed-by: Laurence Oberman 
Tested-by: Laurence Oberman 
Reviewed-by: Johannes Thumshirn 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: sg: disable SET_FORCE_LOW_DMA

2018-01-23T18:50:14+00:00

commit 745dfa0d8ec26b24f3304459ff6e9eacc5c8351b upstream.

The ioctl SET_FORCE_LOW_DMA has never worked since the initial git
check-in, and the respective setting is nowadays handled correctly. So
disable it entirely.

Signed-off-by: Hannes Reinecke 
Reviewed-by: Johannes Thumshirn 
Tested-by: Johannes Thumshirn 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: libsas: align sata_device's rps_resp on a cacheline

2017-12-16T09:33:48+00:00

commit c2e8fbf908afd81ad502b567a6639598f92c9b9d upstream.

The rps_resp buffer in ata_device is a DMA target, but it isn't
explicitly cacheline aligned. Due to this, adjacent fields can be
overwritten with stale data from memory on non-coherent architectures.
As a result, the kernel is sometimes unable to communicate with an SATA
device behind a SAS expander.

Fix this by ensuring that the rps_resp buffer is cacheline aligned.

This issue is similar to that fixed by Commit 84bda12af31f93 ("libata:
align ap->sector_buf") and Commit 4ee34ea3a12396f35b26 ("libata: Align
ata_device's id on a cacheline").

Signed-off-by: Huacai Chen 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: libiscsi: add lock around task lists to fix list corruption regression

2017-03-26T10:13:19+00:00

commit 6f8830f5bbab16e54f261de187f3df4644a5b977 upstream.

There's a rather long standing regression from the commit "libiscsi:
Reduce locking contention in fast path"

Depending on iSCSI target behavior, it's possible to hit the case in
iscsi_complete_task where the task is still on a pending list
(!list_empty(&task->running)).  When that happens the task is removed
from the list while holding the session back_lock, but other task list
modification occur under the frwd_lock.  That leads to linked list
corruption and eventually a panicked system.

Rather than back out the session lock split entirely, in order to try
and keep some of the performance gains this patch adds another lock to
maintain the task lists integrity.

Major enterprise supported kernels have been backing out the lock split
for while now, thanks to the efforts at IBM where a lab setup has the
most reliable reproducer I've seen on this issue.  This patch has been
tested there successfully.

Signed-off-by: Chris Leech 
Fixes: 659743b02c41 ("[SCSI] libiscsi: Reduce locking contention in fast path")
Reported-by: Prashantha Subbarao 
Reviewed-by: Guilherme G. Piccoli 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: use 'scsi_device_from_queue()' for scsi_dh

2017-03-12T05:37:26+00:00

commit 857de6e00778738dc3d61f75acbac35bdc48e533 upstream.

The device handler needs to check if a given queue belongs to a scsi
device; only then does it make sense to attach a device handler.

[mkp: dropped flags]

Signed-off-by: Hannes Reinecke 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: Add intermediate STARGET_REMOVE state to scsi_target_state

2016-06-01T19:15:54+00:00

commit f05795d3d771f30a7bdc3a138bf714b06d42aa95 upstream.

Add intermediate STARGET_REMOVE state to scsi_target_state to avoid
running into the BUG_ON() in scsi_target_reap(). The STARGET_REMOVE
state is only valid in the path from scsi_remove_target() to
scsi_target_destroy() indicating this target is going to be removed.

This re-fixes the problem introduced in commits bc3f02a795d3 ("[SCSI]
scsi_remove_target: fix softlockup regression on hot remove") and
40998193560d ("scsi: restart list search after unlock in
scsi_remove_target") in a more comprehensive way.

[mkp: Included James' fix for scsi_target_destroy()]

Signed-off-by: Johannes Thumshirn 
Fixes: 40998193560dab6c3ce8d25f4fa58a23e252ef38
Reported-by: Sergey Senozhatsky 
Tested-by: Sergey Senozhatsky 
Reviewed-by: Ewan D. Milne 
Reviewed-by: Hannes Reinecke 
Reviewed-by: James Bottomley 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'mkp-fixes' into fixes

2015-12-03T17:32:33+00:00

scsi: report 'INQUIRY result too short' once per host

2015-11-19T17:12:16+00:00

Some host adapters (e.g. Hyper-V storvsc) are known for not respecting
the SPC-2/3/4 requirement for 'INQUIRY data (see table ...) shall
contain at least 36 bytes'. As a result we get tons on 'scsi 0:7:1:1:
scsi scan: INQUIRY result too short (5), using 36' messages on
console. This can be problematic for slow consoles. Introduce
short_inquiry flag in struct Scsi_Host to print the message once per
host.

Signed-off-by: Vitaly Kuznetsov 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Martin K. Petersen

scsi: use host wide tags by default

2015-11-10T01:11:57+00:00

This patch changes the !blk-mq path to the same defaults as the blk-mq
I/O path by always enabling block tagging, and always using host wide
tags.  We've had blk-mq available for a few releases so bugs with
this mode should have been ironed out, and this ensures we get better
coverage of over tagging setup over different configs.

Signed-off-by: Christoph Hellwig 
Acked-by: Jens Axboe 
Reviewed-by: Hannes Reinecke 
Signed-off-by: James Bottomley

Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

2015-09-12T02:00:42+00:00

Pull SCSI target updates from Nicholas Bellinger:
 "Here are the outstanding target-pending updates for v4.3-rc1.

  Mostly bug-fixes and minor changes this round.  The fallout from the
  big v4.2-rc1 RCU conversion have (thus far) been minimal.

  The highlights this round include:

   - Move sense handling routines into scsi_common code (Sagi)

   - Return ABORTED_COMMAND sense key for PI errors (Sagi)

   - Add tpg_enabled_sendtargets attribute for disabled iscsi-target
     discovery (David)

   - Shrink target struct se_cmd by rearranging fields (Roland)

   - Drop iSCSI use of mutex around max_cmd_sn increment (Roland)

   - Replace iSCSI __kernel_sockaddr_storage with sockaddr_storage (Andy +
     Chris)

   - Honor fabric max_data_sg_nents I/O transfer limit (Arun + Himanshu +
     nab)

   - Fix EXTENDED_COPY >= v4.1 regression OOPsen (Alex + nab)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (37 commits)
  target: use stringify.h instead of own definition
  target/user: Fix UFLAG_UNKNOWN_OP handling
  target: Remove no-op conditional
  target/user: Remove unused variable
  target: Fix max_cmd_sn increment w/o cmdsn mutex regressions
  target: Attach EXTENDED_COPY local I/O descriptors to xcopy_pt_sess
  target/qla2xxx: Honor max_data_sg_nents I/O transfer limit
  target/iscsi: Replace __kernel_sockaddr_storage with sockaddr_storage
  target/iscsi: Replace conn->login_ip with login_sockaddr
  target/iscsi: Keep local_ip as the actual sockaddr
  target/iscsi: Fix np_ip bracket issue by removing np_ip
  target: Drop iSCSI use of mutex around max_cmd_sn increment
  qla2xxx: Update tcm_qla2xxx module description to 24xx+
  iscsi-target: Add tpg_enabled_sendtargets for disabled discovery
  drivers: target: Drop unlikely before IS_ERR(_OR_NULL)
  target: check DPO/FUA usage for COMPARE AND WRITE
  target: Shrink struct se_cmd by rearranging fields
  target: Remove cmd->se_ordered_id (unused except debug log lines)
  target: add support for START_STOP_UNIT SCSI opcode
  target: improve unsupported opcode message
  ...