linux-toradex.git/drivers/scsi/scsi_scan.c, branch v3.10.33

Merge SCSI misc branch into isci-for-3.6 tag

2012-10-02T07:55:12+00:00

[SCSI] Disable DIF on Hitachi Ultrastar 15K300

2012-09-24T08:11:00+00:00

Hitachi Ultrastar 15K300 is quirky. Disable T10 PI (DIF).

Signed-off-by: Martin K. Petersen 
Signed-off-by: James Bottomley

[SCSI] Fix 'Device not ready' issue on mpt2sas

2012-08-22T05:42:54+00:00

This is a particularly nasty SCSI ATA Translation Layer (SATL) problem.

SAT-2 says (section 8.12.2)

        if the device is in the stopped state as the result of
        processing a START STOP UNIT command (see 9.11), then the SATL
        shall terminate the TEST UNIT READY command with CHECK CONDITION
        status with the sense key set to NOT READY and the additional
        sense code of LOGICAL UNIT NOT READY, INITIALIZING COMMAND
        REQUIRED;

mpt2sas internal SATL seems to implement this.  The result is very confusing
standby behaviour (using hdparm -y).  If you suspend a drive and then send
another command, usually it wakes up.  However, if the next command is a TEST
UNIT READY, the SATL sees that the drive is suspended and proceeds to follow
the SATL rules for this, returning NOT READY to all subsequent commands.  This
means that the ordering of TEST UNIT READY is crucial: if you send TUR and
then a command, you get a NOT READY to both back.  If you send a command and
then a TUR, you get GOOD status because the preceeding command woke the drive.

This bit us badly because

commit 85ef06d1d252f6a2e73b678591ab71caad4667bb
Author: Tejun Heo 
Date:   Fri Jul 1 16:17:47 2011 +0200

    block: flush MEDIA_CHANGE from drivers on close(2)

Changed our ordering on TEST UNIT READY commands meaning that SATA drives
connected to an mpt2sas now suspend and refuse to wake (because the mpt2sas
SATL sees the suspend *before* the drives get awoken by the next ATA command)
resulting in lots of failed commands.

The standard is completely nuts forcing this inconsistent behaviour, but we
have to work around it.

The fix for this is twofold:

   1. Set the allow_restart flag so we wake the drive when we see it has been
      suspended

   2. Return all TEST UNIT READY status directly to the mid layer without any
      further error handling which prevents us causing error handling which
      may offline the device just because of a media check TUR.

Reported-by: Matthias Prager 
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley

[SCSI] Revert "[SCSI] fix async probe regression"

2012-07-20T08:25:56+00:00

This reverts commit 43a8d39d0137612c336aa8bbb2cb886a79772ffb.

Commit 43a8d39d fixed the fact that wait_for_device_probe() was unable
to flush sd probe work.  Now that sd probe work is once again flushable
via wait_for_device_probe() this workaround is no longer needed.

Signed-off-by: Dan Williams 
Tested-by: Eldad Zack 
Signed-off-by: James Bottomley

[SCSI] cleanup usages of scsi_complete_async_scans

2012-07-20T08:25:22+00:00

Now that scsi registers its async scan work with the async subsystem,
wait_for_device_probe() is sufficient for ensuring all scanning is
complete.

[jejb: fix merge problems with eea03c20ae38 Make wait_for_device_probe() also do scsi_complete_async_scans()]
Signed-off-by: Dan Williams 
Tested-by: Eldad Zack 
Signed-off-by: James Bottomley

[SCSI] queue async scan work to an async_schedule domain

2012-07-20T08:09:27+00:00

This is preparation to enable async_synchronize_full() to be used as a
replacement for scsi_complete_async_scans(), i.e. to stop leaking scsi
internal details where they are not needed.

Signed-off-by: Dan Williams 
Tested-by: Eldad Zack 
Signed-off-by: James Bottomley

[SCSI] fix hot unplug vs async scan race

2012-07-20T07:58:45+00:00

The following crash results from cases where the end_device has been
removed before scsi_sysfs_add_sdev has had a chance to run.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
 IP: [] sysfs_create_dir+0x32/0xb6
 ...
 Call Trace:
  [] kobject_add_internal+0x120/0x1e3
  [] ? trace_hardirqs_on+0xd/0xf
  [] kobject_add_varg+0x41/0x50
  [] kobject_add+0x64/0x66
  [] device_add+0x12d/0x63a
  [] ? _raw_spin_unlock_irqrestore+0x47/0x56
  [] ? module_refcount+0x89/0xa0
  [] scsi_sysfs_add_sdev+0x4e/0x28a
  [] do_scan_async+0x9c/0x145

...teach scsi_sysfs_add_devices() to check for deleted devices() before
trying to add them, and teach scsi_remove_target() how to remove targets
that have not been added via device_add().

Cc: 
Reported-by: Dariusz Majchrzak 
Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley

[SCSI] fix async probe regression

2012-05-30T09:37:07+00:00

Commit a7a20d1 "[SCSI] sd: limit the scope of the async probe domain"
moved sd probe work out of reach of wait_for_device_probe().  Allow it
to be synced via scsi_complete_async_scans().

Reported-by: Meelis Roos 
Tested-by: Meelis Roos 
Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley

Merge 3.3-rc7 into usb-next

2012-03-12T16:13:31+00:00

This resolves the conflict with drivers/usb/host/ehci-fsl.h that
happened with changes in Linus's and this branch at the same time.

Signed-off-by: Greg Kroah-Hartman

[SCSI] scsi_scan: Fix 'Poison overwritten' warning caused by using freed 'shost'

2012-02-18T14:52:48+00:00

In do_scan_async(), calling scsi_autopm_put_host(shost) may reference
freed shost, and cause Posison overwitten warning.
Yes, this case can happen, for example, an USB is disconnected just
when do_scan_async() thread starts to run, then scsi_host_put() called
in scsi_finish_async_scan() will lead to shost be freed(because the
refcount of shost->shost_gendev decreases to 1 after USB disconnects),
at this point, if references shost again, system will show following
warning msg.

To make scsi_autopm_put_host(shost) always reference a valid shost,
put it just before scsi_host_put() in function
scsi_finish_async_scan().

[  299.281565] =============================================================================
[  299.281634] BUG kmalloc-4096 (Tainted: G          I ): Poison overwritten
[  299.281682] -----------------------------------------------------------------------------
[  299.281684]
[  299.281752] INFO: 0xffff880056c305d0-0xffff880056c305d0. First byte
0x6a instead of 0x6b
[  299.281816] INFO: Allocated in scsi_host_alloc+0x4a/0x490 age=1688
cpu=1 pid=2004
[  299.281870] 	__slab_alloc+0x617/0x6c1
[  299.281901] 	__kmalloc+0x28c/0x2e0
[  299.281931] 	scsi_host_alloc+0x4a/0x490
[  299.281966] 	usb_stor_probe1+0x5b/0xc40 [usb_storage]
[  299.282010] 	storage_probe+0xa4/0xe0 [usb_storage]
[  299.282062] 	usb_probe_interface+0x172/0x330 [usbcore]
[  299.282105] 	driver_probe_device+0x257/0x3b0
[  299.282138] 	__driver_attach+0x103/0x110
[  299.282171] 	bus_for_each_dev+0x8e/0xe0
[  299.282201] 	driver_attach+0x26/0x30
[  299.282230] 	bus_add_driver+0x1c4/0x430
[  299.282260] 	driver_register+0xb6/0x230
[  299.282298] 	usb_register_driver+0xe5/0x270 [usbcore]
[  299.282337] 	0xffffffffa04ab03d
[  299.282364] 	do_one_initcall+0x47/0x230
[  299.282396] 	sys_init_module+0xa0f/0x1fe0
[  299.282429] INFO: Freed in scsi_host_dev_release+0x18a/0x1d0 age=85
cpu=0 pid=2008
[  299.282482] 	__slab_free+0x3c/0x2a1
[  299.282510] 	kfree+0x296/0x310
[  299.282536] 	scsi_host_dev_release+0x18a/0x1d0
[  299.282574] 	device_release+0x74/0x100
[  299.282606] 	kobject_release+0xc7/0x2a0
[  299.282637] 	kobject_put+0x54/0xa0
[  299.282668] 	put_device+0x27/0x40
[  299.282694] 	scsi_host_put+0x1d/0x30
[  299.282723] 	do_scan_async+0x1fc/0x2b0
[  299.282753] 	kthread+0xdf/0xf0
[  299.282782] 	kernel_thread_helper+0x4/0x10
[  299.282817] INFO: Slab 0xffffea00015b0c00 objects=7 used=7 fp=0x
      (null) flags=0x100000000004080
[  299.282882] INFO: Object 0xffff880056c30000 @offset=0 fp=0x          (null)
[  299.282884]
...

Signed-off-by: Huajun Li 
Cc: stable@kernel.org
Acked-by: Alan Stern 
Signed-off-by: James Bottomley