linux-toradex.git/drivers/scsi/scsi_sysfs.c, branch v4.4.129

scsi: avoid a permanent stop of the scsi device's request queue

2017-01-09T07:07:48+00:00

commit d2a145252c52792bc59e4767b486b26c430af4bb upstream.

A race between scanning and fc_remote_port_delete() may result in a
permanent stop if the device gets blocked before scsi_sysfs_add_sdev()
and unblocked after.  The reason is that blocking a device sets both the
SDEV_BLOCKED state and the QUEUE_FLAG_STOPPED.  However,
scsi_sysfs_add_sdev() unconditionally sets SDEV_RUNNING which causes the
device to be ignored by scsi_target_unblock() and thus never have its
QUEUE_FLAG_STOPPED cleared leading to a device which is apparently
running but has a stopped queue.

We actually have two places where SDEV_RUNNING is set: once in
scsi_add_lun() which respects the blocked flag and once in
scsi_sysfs_add_sdev() which doesn't.  Since the second set is entirely
spurious, simply remove it to fix the problem.

Reported-by: Zengxi Chen 
Signed-off-by: Wei Fang 
Reviewed-by: Ewan D. Milne 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: ignore errors from scsi_dh_add_device()

2016-08-16T07:30:48+00:00

commit 221255aee67ec1c752001080aafec0c4e9390d95 upstream.

device handler initialisation might fail due to a number of
reasons. But as device_handlers are optional this shouldn't
cause us to disable the device entirely.
So just ignore errors from scsi_dh_add_device().

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

Revert "scsi: fix soft lockup in scsi_remove_target() on module removal"

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

commit 305c2e71b3d733ec065cb716c76af7d554bd5571 upstream.

Now that we've done a more comprehensive fix with the intermediate
target state we can remove the previous hack introduced with commit
90a88d6ef88e ("scsi: fix soft lockup in scsi_remove_target() on module
removal").

Signed-off-by: Johannes Thumshirn 
Reviewed-by: Ewan D. Milne 
Reviewed-by: Hannes Reinecke 
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

scsi: fix soft lockup in scsi_remove_target() on module removal

2016-02-25T20:01:17+00:00

commit 90a88d6ef88edcfc4f644dddc7eef4ea41bccf8b upstream.

This softlockup is currently happening:

[  444.088002] NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [kworker/1:1:29]
[  444.088002] Modules linked in: lpfc(-) qla2x00tgt(O) qla2xxx_scst(O) scst_vdisk(O) scsi_transport_fc libcrc32c scst(O) dlm configfs nfsd lockd grace nfs_acl auth_rpcgss sunrpc ed
d snd_pcm_oss snd_mixer_oss snd_seq snd_seq_device dm_mod iTCO_wdt snd_hda_codec_realtek snd_hda_codec_generic gpio_ich iTCO_vendor_support ppdev snd_hda_intel snd_hda_codec snd_hda
_core snd_hwdep tg3 snd_pcm snd_timer libphy lpc_ich parport_pc ptp acpi_cpufreq snd pps_core fjes parport i2c_i801 ehci_pci tpm_tis tpm sr_mod cdrom soundcore floppy hwmon sg 8250_
fintek pcspkr i915 drm_kms_helper uhci_hcd ehci_hcd drm fb_sys_fops sysimgblt sysfillrect syscopyarea i2c_algo_bit usbcore button video usb_common fan ata_generic ata_piix libata th
ermal
[  444.088002] CPU: 1 PID: 29 Comm: kworker/1:1 Tainted: G           O    4.4.0-rc5-2.g1e923a3-default #1
[  444.088002] Hardware name: FUJITSU SIEMENS ESPRIMO E           /D2164-A1, BIOS 5.00 R1.10.2164.A1               05/08/2006
[  444.088002] Workqueue: fc_wq_4 fc_rport_final_delete [scsi_transport_fc]
[  444.088002] task: f6266ec0 ti: f6268000 task.ti: f6268000
[  444.088002] EIP: 0060:[] EFLAGS: 00000286 CPU: 1
[  444.088002] EIP is at _raw_spin_unlock_irqrestore+0x14/0x20
[  444.088002] EAX: 00000286 EBX: f20d3800 ECX: 00000002 EDX: 00000286
[  444.088002] ESI: f50ba800 EDI: f2146848 EBP: f6269ec8 ESP: f6269ec8
[  444.088002]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[  444.088002] CR0: 8005003b CR2: 08f96600 CR3: 363ae000 CR4: 000006d0
[  444.088002] Stack:
[  444.088002]  f6269eec c066b0f7 00000286 f2146848 f50ba808 f50ba800 f50ba800 f2146a90
[  444.088002]  f2146848 f6269f08 f8f0a4ed f3141000 f2146800 f2146a90 f619fa00 00000040
[  444.088002]  f6269f40 c026cb25 00000001 166c6392 00000061 f6757140 f6136340 00000004
[  444.088002] Call Trace:
[  444.088002]  [] scsi_remove_target+0x167/0x1c0
[  444.088002]  [] fc_rport_final_delete+0x9d/0x1e0 [scsi_transport_fc]
[  444.088002]  [] process_one_work+0x155/0x3e0
[  444.088002]  [] worker_thread+0x37/0x490
[  444.088002]  [] kthread+0x9b/0xb0
[  444.088002]  [] ret_from_kernel_thread+0x21/0x40

What appears to be happening is that something has pinned the target
so it can't go into STARGET_DEL via final release and the loop in
scsi_remove_target spins endlessly until that happens.

The fix for this soft lockup is to not keep looping over a device that
we've called remove on but which hasn't gone into DEL state.  This
patch will retain a simplistic memory of the last target and not keep
looping over it.

Reported-by: Sebastian Herbszt 
Tested-by: Sebastian Herbszt 
Fixes: 40998193560dab6c3ce8d25f4fa58a23e252ef38
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'mkp-fixes' into fixes

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

Revert "scsi: Fix a bdi reregistration race"

2015-12-02T19:53:44+00:00

The SCSI sd driver probes SCSI devices asynchronously. The sd_remove()
function, called indirectly by device_del(), waits until asynchronous
probing has finished. Since the block layer queue must only be cleaned
up after probing has finished, device_del() has to be called before
blk_cleanup_queue(). Hence revert commit bf2cf3baa20b.

Signed-off-by: Bart Van Assche 
Cc: 
Signed-off-by: James Bottomley

scsi_sysfs: protect against double execution of __scsi_remove_device()

2015-11-19T17:15:09+00:00

On some host errors storvsc module tries to remove sdev by scheduling a job
which does the following:

   sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
   if (sdev) {
       scsi_remove_device(sdev);
       scsi_device_put(sdev);
   }

While this code seems correct the following crash is observed:

 general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
 RIP: 0010:[]  [] bdi_destroy+0x39/0x220
 ...
 [] ? _raw_spin_unlock_irq+0x2c/0x40
 [] blk_cleanup_queue+0x17b/0x270
 [] __scsi_remove_device+0x54/0xd0 [scsi_mod]
 [] scsi_remove_device+0x2b/0x40 [scsi_mod]
 [] storvsc_remove_lun+0x3d/0x60 [hv_storvsc]
 [] process_one_work+0x1b1/0x530
 ...

The problem comes with the fact that many such jobs (for the same device)
are being scheduled simultaneously. While scsi_remove_device() uses
shost->scan_mutex and scsi_device_lookup() will fail for a device in
SDEV_DEL state there is no protection against someone who did
scsi_device_lookup() before we actually entered __scsi_remove_device(). So
the whole scenario looks like that: two callers do simultaneous (or
preemption happens) calls to scsi_device_lookup() ant these calls succeed
for both of them, after that they try doing scsi_remove_device().
shost->scan_mutex only serializes their calls to __scsi_remove_device()
and we end up doing the cleanup path twice.

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

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2015-11-14T04:35:54+00:00

Pull final round of SCSI updates from James Bottomley:
 "Sorry for the delay in this patch which was mostly caused by getting
  the merger of the mpt2/mpt3sas driver, which was seen as an essential
  item of maintenance work to do before the drivers diverge too much.
  Unfortunately, this caused a compile failure (detected by linux-next),
  which then had to be fixed up and incubated.

  In addition to the mpt2/3sas rework, there are updates from pm80xx,
  lpfc, bnx2fc, hpsa, ipr, aacraid, megaraid_sas, storvsc and ufs plus
  an assortment of changes including some year 2038 issues, a fix for a
  remove before detach issue in some drivers and a couple of other minor
  issues"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (141 commits)
  mpt3sas: fix inline markers on non inline function declarations
  sd: Clear PS bit before Mode Select.
  ibmvscsi: set max_lun to 32
  ibmvscsi: display default value for max_id, max_lun and max_channel.
  mptfusion: don't allow negative bytes in kbuf_alloc_2_sgl()
  scsi: pmcraid: replace struct timeval with ktime_get_real_seconds()
  mvumi: 64bit value for seconds_since1970
  be2iscsi: Fix bogus WARN_ON length check
  scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice
  mpt3sas: Bump mpt3sas driver version to 09.102.00.00
  mpt3sas: Single driver module which supports both SAS 2.0 & SAS 3.0 HBAs
  mpt2sas, mpt3sas: Update the driver versions
  mpt3sas: setpci reset kernel oops fix
  mpt3sas: Added OEM Gen2 PnP ID branding names
  mpt3sas: Refcount fw_events and fix unsafe list usage
  mpt3sas: Refcount sas_device objects and fix unsafe list usage
  mpt3sas: sysfs attribute to report Backup Rail Monitor Status
  mpt3sas: Ported WarpDrive product SSS6200 support
  mpt3sas: fix for driver fails EEH, recovery from injected pci bus error
  mpt3sas: Manage MSI-X vectors according to HBA device type
  ...

Merge tag '4.4-scsi-mkp' into misc

2015-11-12T12:06:18+00:00

SCSI queue for 4.4.

Signed-off-by: Martin K. Petersen