Here, If devm_ioremap will fail. It will return NULL.
Then hpriv->base = NULL - 0x20000; Kernel can run into
a NULL-pointer dereference. This error check will avoid
NULL pointer dereference.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org

For an ATA device supporting the sense data reporting feature set, a
failed command will trigger the execution of ata_eh_request_sense if
the result task file of the failed command has the ATA_SENSE bit set
(sense data available bit). ata_eh_request_sense executes the REQUEST
SENSE DATA EXT command to retrieve the sense data of the failed
command. On success of REQUEST SENSE DATA EXT, the ATA_SENSE bit will
NOT be set (the command succeeded) but ata_eh_request_sense
nevertheless tests the availability of sense data by testing that bit
presence in the result tf of the REQUEST SENSE DATA EXT command.  This
leads us to falsely assume that request sense data failed and to the
warning message:

atax.xx: request sense failed stat 50 emask 0

Upon success of REQUEST SENSE DATA EXT, set the ATA_SENSE bit in the
result task file command so that sense data can be returned by
ata_eh_request_sense.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org

Marko reports that CX1-JB512-HP shows the same timeout issues as
CX1-JB256-HP.  Let's apply MAX_SEC_128 to all devices in the series.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Marko Koski-Vähälä <marko@koski-vahala.com>
Cc: stable@vger.kernel.org # v3.19+

Pull another libata patch from Tejun Heo:
 "One more patch from Adam added.

  It makes libata skip probing for NCQ prio unless the feature is
  explicitly requested by the user. This is necessary because some
  controllers lock up after the optional feature is probed"

* 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ata: avoid probing NCQ Prio Support if not explicitly requested

Previously, when the ata device was being initialized we were
probing for NCQ prio support by checking the identify information
and also checking the log page that holds information about ncq prio
support.

This caused an error on an Intel HBA so the code is now updated to
only probe for NCQ prio support when the sysfs variable controlling
NCQ prio support is enabled.

tj: Update formatting, switch to spin_[un]lock_irq() and update
    locking a bit, use REVALIDATE instead of RESET, and return -EIO
    instead of -EINVAL on config failure.

Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Pull libata updates from Tejun Heo:

 - Adam added opt-in ATA command priority support.

 - There are machines which hide multiple nvme devices behind an ahci
   BAR. Dan Williams proposed a solution to force-switch the mode but
   deemed too hackishd. People are gonna discuss the proper way to
   handle the situation in nvme standard meetings. For now, detect and
   warn about the situation.

 - Low level driver specific changes.

Christoph Hellwig pipes in about the hidden nvme warning:
 "I wish that was the case. We've pretty much agreed that we'll want to
  implement it as a virtual PCIe root bridge, similar to Intels other
  'innovation' VMD that we work around that way.

  But Intel management has apparently decided that they don't want to
  spend more cycles on this now that Lenovo has an optional BIOS that
  doesn't force this broken mode anymore, and no one outside of Intel
  has enough information to implement something like this.

  So for now I guess this warning is it, until Intel reconsideres and
  spends resources on fixing up the damage their Chipset people caused"

* 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ahci: warn about remapped NVMe devices
  ahci-remap.h: add ahci remapping definitions
  nvme: move NVMe class code to pci_ids.h
  pata: imx: support controller modes up to PIO4
  pata: imx: add support of setting timings for PIO modes
  pata: imx: set controller PIO mode with .set_piomode callback
  pata: imx: sort headers out
  ata: set ncq_prio_enabled iff device has support
  ata: ATA Command Priority Disabled By Default
  ata: Enabling ATA Command Priorities
  block: Add iocontext priority to request
  ahci: qoriq: added ls1046a platform support

Pull documentation update from Jonathan Corbet:
 "These are the documentation changes for 4.10.

  It's another busy cycle for the docs tree, as the sphinx conversion
  continues. Highlights include:

   - Further work on PDF output, which remains a bit of a pain but
     should be more solid now.

   - Five more DocBook template files converted to Sphinx. Only 27 to
     go... Lots of plain-text files have also been converted and
     integrated.

   - Images in binary formats have been replaced with more
     source-friendly versions.

   - Various bits of organizational work, including the renaming of
     various files discussed at the kernel summit.

   - New documentation for the device_link mechanism.

  ... and, of course, lots of typo fixes and small updates"

* tag 'docs-4.10' of git://git.lwn.net/linux: (193 commits)
  dma-buf: Extract dma-buf.rst
  Update Documentation/00-INDEX
  docs: 00-INDEX: document directories/files with no docs
  docs: 00-INDEX: remove non-existing entries
  docs: 00-INDEX: add missing entries for documentation files/dirs
  docs: 00-INDEX: consolidate process/ and admin-guide/ description
  scripts: add a script to check if Documentation/00-INDEX is sane
  Docs: change sh -> awk in REPORTING-BUGS
  Documentation/core-api/device_link: Add initial documentation
  core-api: remove an unexpected unident
  ppc/idle: Add documentation for powersave=off
  Doc: Correct typo, "Introdution" => "Introduction"
  Documentation/atomic_ops.txt: convert to ReST markup
  Documentation/local_ops.txt: convert to ReST markup
  Documentation/assoc_array.txt: convert to ReST markup
  docs-rst: parse-headers.pl: cleanup the documentation
  docs-rst: fix media cleandocs target
  docs-rst: media/Makefile: reorganize the rules
  docs-rst: media: build SVG from graphviz files
  docs-rst: replace bayer.png by a SVG image
  ...

SCT Write Same support had been introduced with
commit 7b2030942859 ("libata: Add support for SCT Write Same")

Some problems, namely excessive userspace segfaults, had been reported at

  http://lkml.kernel.org/r/20160908192736.GA4356@gmail.com

This lead to commit 0ce1b18c42a5 ("libata: Some drives failing on
SCT Write Same") which strived to disable SCT Write Same on !ZAC devices.
Due to the way this was done and to the logic in sd_config_write_same(),
this didn't work for those devices that have
->max_ws_blocks > SD_MAX_WS10_BLOCKS: for these, ->no_write_same and
->max_write_same_sectors would still be non-zero,
but ->ws10 == ->ws16 == 0. This would cause sd_setup_write_same_cmnd() to
demultiplex REQ_OP_WRITE_SAME requests to WRITE_SAME, and these in turn
aren't supported by libata-scsi:

  EXT4-fs (dm-1): Delayed block allocation failed for inode 2625094 at
                  logical offset 2032 with max blocks 2 with error 121
  EXT4-fs (dm-1): This should not happen!! Data will be lost

121 == EREMOTEIO is what scsi_io_completion() asserts in case of
invalid opcodes.

Back to the original problem of userspace segfaults: this can be tracked
down to ata_format_sct_write_same() overwriting the input page. Sometimes,
this page is ZERO_PAGE(0) which ceases to be filled with zeros from that
point on. Since ZERO_PAGE(0) is used for userspace .bss mappings, code of
the following is doomed:

  static char *a = NULL; /* .bss */
  ...
  if (a)
    *a = 'a';

This problem is not solved by disabling SCT Write Same for !ZAC devices
only.

It can certainly be fixed, but the final release is quite close -- so
disable SCT Write Same for all ATA devices rather than introducing some
SCT key buffer allocation schemes at this point.

Fixes: 7b2030942859 ("libata: Add support for SCT Write Same")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Some Intel ahci implementations have a completely broken remapping mode
where they hide one or more NVMe devices behind the bar of an AHCI device.

Intel refuses to let the OS reprogram the BIOS to switch out of this
mode at runtime, and so far we're not come up with another good way
to undo the mess that the Chipset people created.  So for now the only
thing we can do is to alert users about this situation and switch to the
faster and much saner so called "AHCI" mode insted of the RAID mode in
the BIOS so that the BIOS does not hide the NVMe devices from us.

The sitation is even worse as at least one vendor (thanks a lot Lenovo..)
has started hardcoding their BIOS into the "RAID" mode even for laptops
that don't use AHCI _at all_ and just have a single NVMe device.  For now
there is an unspported Linux-only BIOS that undoes this braindamage,
but we'll have to see if things are getting better or worse from here.

Based on an earlier patch from Dan Williams <dan.j.williams@intel.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

If the nr-ports property is missing ata_host_alloc_pinfo is called with
n_ports = 0. This results in host->ports[0] = NULL which later makes
mv_init_host() oops when dereferencing this pointer.

Instead be a bit more cooperative and fail the probing with an error
message.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Tejun Heo <tj@kernel.org>