drm: omapdrm: Move supported outputs feature to dss driver

The supported outputs feature is specific to the DSS, move it from the
omap_dss_features structure to the dss driver.

The omap_dss_features structure is now empty and can be removed.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move DSS_FCK feature to dss driver

The FEAT_PARAM_DSS_FCK feature is specific to the DSS, move it from the
omap_dss_features structure to the dss driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move PCD, LINEWIDTH and DOWNSCALE features to dispc driver

The FEAT_PARAM_DSS_PCD, FEAT_PARAM_LINEWIDTH and FEAT_PARAM_DOWNSCALE
features are specific to the DISPC, move them from the omap_dss_features
structure to the dispc driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move FEAT_PARAM_DSI* features to dsi driver

The FEAT_PARAM_DSI* features are specific to the DSI, move them from the
omap_dss_features structure to the dsi driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move FEAT_* features to dispc driver

All the remaining FEAT_* features are specific to the DISPC, move them
from the omap_dss_features structure to the dispc driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move FEAT_LCD_CLK_SRC feature to dss_features structure

The FEAT_LCD_CLK_SRC feature is specific to the DSS, move it from the
omap_dss_features structure to the dss_features structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move FEAT_DPI_USES_VDDS_DSI feature to dpi code

The FEAT_DPI_USES_VDDS_DSI feature is specific to the DPI, move it from
the omap_dss_features structure to the dpi code.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move FEAT_HDMI_* features to hdmi4 driver

The FEAT_HDMI_* features are specific to the HDMI4, move them from the
omap_dss_features structure to the hdmi4 driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move FEAT_DSI_* features to dsi driver

The FEAT_DSI_* features are specific to the DSI, move them from the
omap_dss_features structure to the dsi driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move FEAT_VENC_REQUIRES_TV_DAC_CLK to venc driver

The FEAT_VENC_REQUIRES_TV_DAC_CLK is specific to the VENC, move it from
the omap_dss_features structure to the venc driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move reg_fields to dispc_features structure

The reg_fields feature describes DISPC registers only. Move it from the
omap_dss_features structure to the dispc_features structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move DISPC_CLK_SWITCH reg feature to struct dss_features

The register belongs to the DSS, move the feature to the dss_features
structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move num_ovls and num_mgrs to dispc_features structure

The num_ovls and num_mgrs are dispc features. Move them from the
omap_dss_features structure to the dispc_features structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move overlay caps features to dispc_features structure

The overlay_caps is a dispc feature. Move it from the omap_dss_features
structure to the dispc_features structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move color modes feature to dispc_features structure

The supported_color_modes is a dispc feature. Move it from the
omap_dss_features structure to the dispc_features structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move size unit features to dispc_features structure

The buffer_size_unit and burst_size_unit are dispc features. Move them
from the omap_dss_features structure to the dispc_features structure.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move shutdown() handler from core to dss

In preparation for removal of the core module, move the shutdown()
handler from core to dss.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Move all debugfs code from core to dss

debugfs code is spread between the core and dss drivers. In preparation
for removal of the core driver, move it all to the dss driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dss: Initialize DSS internal features at probe time

The DSS internal features are derived from the platform device
compatible string which is available at probe time. Don't delay
initialization until bind time. This prepares for the merge of the two
DSS features structures that will be needed before the DSS is bound.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dss: Use supported outputs instead of display types

The dss driver uses the supported display types to check whether the DSS
has SDI, VENC or HDMI outputs. We can instead use the supported outputs
the provide the same information. This removes the last use of the
supported display types, that we can then remove as well.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dss: Select features based on compatible string

Use the compatible string instead of the OMAP SoC revision to determine
device features. The various OMAP3-based SoCs can't be told apart using
the compatible string, use soc_device_match() to tell them apart.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dpi: Replace OMAP SoC model checks with DSS model

The DPI code only needs to differentiate between major OMAP revisions,
which can be obtained from the DSS compatible string. Replace the OMAP
SoC model checks to prepare for removal of the OMAP SoC version platform
data.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dispc: Select features based on compatible string

Use the compatible string instead of the OMAP SoC revision to determine
device features. On OMAP34xx the features depend on the ES revision that
can not be determined from the compatible string. Use soc_device_match()
in that case.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: Don't forward set_min_bus_tput() to no-op platform code

The OMAP implementation of the set_min_bus_tput() API is a no-op.
There's no point in forwarding the driver calls to the platform code.
Remove the use of the related platform data callback, but keep the
internal function as a reminder that the feature will need to be
implemented when the OMAP platform will provide support.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dsi: Handle pin muxing internally

Don't rely on callback functions provided by the platform, but access
the syscon internally to mux the DSI pins.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dsi: Store DSI model and PLL hardware data in OF data

The DSI PLL hardware data and DSS channels are selected based on the
OMAP SoC model. There's no need for fine-grained model information, as
the driver only needs to differentiate between OMAP3, OMAP4 and OMAP5.
As this can be done through the DSI compatible string, store the
corresponding information in OF match data instead to avoid accessing
the OMAP SoC model.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dss: Split operations out of dss_features structure

Move the two function pointers to a new dss_ops structure. This will
allow merging the dss_features and omap_dss_features structures without
having to expose the DPI source selection and LCD clock muxing functions
in header files.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: hdmi: Store PHY features in PHY data structure

PHY features are stored in a global variable, while they should be
properties of the PHY object. As existing OMAP platforms have a single
HDMI PHY this doesn't cause any issue, but doesn't follow the driver
model.

Move the PHY features to the HDMI PHY data structure to follow the
driver model and pave the road for multiple HDMI PHYs support.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: venc: Don't export omap_dss_pal_vm and omap_dss_ntsc_vm

The two variables are never used outside of their compilation unit, make
them static.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: dpi: Remove unneeded regulator check

The dpi_display_enable() function ensures that a VDDS_DSI regulator is
available if the DSI uses the VDDS_DSI supply. This is not needed, as a
failure to get the VDDS_DSI supply will result in a probe failure,
dpi_display_enable() will thus never be called in that case.

Remove the check, and replace tests for the FEAT_DPI_USES_VDDS_DSI
feature with a test for the regulator object.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: panel-dpi: Remove unneeded check for OF node

As non-DT booting is no longer supported, the only way to instantiate
the device is through an OF node, which is guaranteed to be present.
Remove the unneeded check.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: connector-analog-tv: Remove unneeded check for OF node

As non-DT booting is no longer supported, the only way to instantiate
the device is through an OF node, which is guaranteed to be present.
Remove the unneeded check.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm: omapdrm: acx565akm: Remove unneeded check for OF node

As non-DT booting is no longer supported, the only way to instantiate
the device is through an OF node, which is guaranteed to be present.
Remove the unneeded check.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

ARM: OMAP2+: Register SoC device attributes from machine .init()

SoC device attributes are registered with a call to
soc_device_register() from the machine .init_late() operation, which is
called from the late initcall, after all drivers built-in drivers have
been probed. This results in the impossibility for drivers to use SoC
device matching in their probe function.

The omap_soc_device_init() function is safe to call from the machine
.init() operation, as all data it depends on is initialized from the
.init_early() operation. Move SoC device attribute registration to
machine .init() like on all other ARM platforms.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: panel-dsi-cm: constify attribute_group structures.

attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.

File size before:
  text    data     bss     dec     hex filename
   4669     464       0    5133    140d panel-dsi-cm.o

File size After adding 'const':
   text    data     bss     dec     hex filename
   4725     400       0    5125    1405 panel-dsi-cm.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: panel-sony-acx565akm: constify attribute_group structures.

attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.

File size before:
   text    data     bss     dec     hex filename
   5147     560       0    5707    164b panel-sony-acx565akm.o

File size After adding 'const':
   text    data     bss     dec     hex filename
   5211     496       0    5707    164b panel-sony-acx565akm.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: constify attribute_group structures.

attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.

File size before:
   text    data     bss     dec     hex filename
   2673     368       0    3041     be1 panel-tpo-td043mtea1.o

File size After adding 'const':
   text    data     bss     dec     hex filename
   2721     304       0    3025     bd1 panel-tpo-td043mtea1.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: dma-buf: Constify dma_buf_ops structures.

dma_buf_ops are not supposed to change at runtime. All functions
working with dma_buf_ops provided by <linux/dma-buf.h> work with
const dma_buf_ops. So mark the non-const structs as const.

File size before:
   text    data     bss     dec     hex filename
   1240     112       0    1352     548 drivers/gpu/drm/omapdrm/omap_gem_dmabuf.o

File size After adding 'const':
   text    data     bss     dec     hex filename
   1352       0       0    1352     548 drivers/gpu/drm/omapdrm/omap_gem_dmabuf.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: omap_display_timings: constify videomode structures

The videomode structures are only copied into the vm field of a
panel_drv_data structure, so they can be const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: displays: encoder-tpd12s015: Support for hot plug detection

Use interrupt handler for hpd GPIO to react to HPD changes.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: displays: connector-hdmi: Support for hot plug detection

If the hpd_gpio is valid, use interrupt handler to react to HPD changes.
In case the hpd_gpio is not valid, try to enable hpd detection on the
encoder if it supports it.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: Support for HDMI hot plug detection

The HPD signal can be used for detecting HDMI cable plug and unplug event
without the need for polling the status of the line.
This will speed up detecting such event because we do not need to wait for
the next poll event to notice the state change.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drm/omap: fix memory leak when FB init fails

omap_framebuffer_create() fails to unref all the gem objects if creating
the FB fails, leading to a memory leak.

Fix the loop so that it goes through all the reffed gem objects.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

Backmerge tag 'v4.13-rc5' into drm-next

Linux 4.13-rc5

There's a really nasty nouveau collision, hopefully someone can take a look
once I pushed this out.

Linux 4.13-rc5

Merge branch 'upstream' of git://git.linux-mips.org/ralf/upstream-linus

Pull MIPS fixes from Ralf Baechle:
 "Another round of MIPS fixes:

   - compressed boot: Ignore a generated .c file

   - VDSO: Fix a register clobber list

   - DECstation: Fix an int-handler.S CPU_DADDI_WORKAROUNDS regression

   - Octeon: Fix recent cleanups that cleaned away a bit too much thus
     breaking the arch side of the EDAC and USB drivers.

   - uasm: Fix duplicate const in "const struct foo const bar[]" which
     GCC 7.1 no longer accepts.

   - Fix race on setting and getting cpu_online_mask

   - Fix preemption issue. To do so cleanly introduce macro to get the
     size of L3 cache line.

   - Revert include cleanup that sometimes results in build error

   - MicroMIPS uses bit 0 of the PC to indicate microMIPS mode. Make
     sure this bit is set for kernel entry as well.

   - Prevent configuring the kernel for both microMIPS and MT. There are
     no such CPUs currently and thus the combination is unsupported and
     results in build errors.

  This has been sitting in linux-next for a few days and has survived
  automated testing by Imagination's test farm. No known regressions
  pending except a number of issues that crept up due to lots of people
  switching to GCC 7.1"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Set ISA bit in entry-y for microMIPS kernels
  MIPS: Prevent building MT support for microMIPS kernels
  MIPS: PCI: Fix smp_processor_id() in preemptible
  MIPS: Introduce cpu_tcache_line_size
  MIPS: DEC: Fix an int-handler.S CPU_DADDI_WORKAROUNDS regression
  MIPS: VDSO: Fix clobber lists in fallback code paths
  Revert "MIPS: Don't unnecessarily include kmalloc.h into <asm/cache.h>."
  MIPS: OCTEON: Fix USB platform code breakage.
  MIPS: Octeon: Fix broken EDAC driver.
  MIPS: gitignore: ignore generated .c files
  MIPS: Fix race on setting and getting cpu_online_mask
  MIPS: mm: remove duplicate "const" qualifier on insn_table

Merge tag 'driver-core-4.13-rc5' of git://git./linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are three firmware core fixes for 4.13-rc5.

  All three of these fix reported issues and have been floating around
  for a few weeks. They have been in linux-next with no reported
  problems"

* tag 'driver-core-4.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  firmware: avoid invalid fallback aborts by using killable wait
  firmware: fix batched requests - send wake up on failure on direct lookups
  firmware: fix batched requests - wake all waiters

Merge tag 'char-misc-4.13-rc5' of git://git./linux/kernel/git/gregkh/char-misc

Pull char/misc fixes from Greg KH:
 "Here are two patches for 4.13-rc5.

  One is a fix for a reported thunderbolt issue, and the other a fix for
  an MEI driver issue. Both have been in linux-next with no reported
  issues"

* tag 'char-misc-4.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  thunderbolt: Do not enumerate more ports from DROM than the controller has
  mei: exclude device from suspend direct complete optimization

Merge tag 'tty-4.13-rc5' of git://git./linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are two tty serial driver fixes for 4.13-rc5. One is a revert of
  a -rc1 patch that turned out to not be a good idea, and the other is a
  fix for the pl011 serial driver.

  Both have been in linux-next with no reported issues"

* tag 'tty-4.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "serial: Delete dead code for CIR serial ports"
  tty: pl011: fix initialization order of QDF2400 E44

Merge tag 'staging-4.13-rc5' of git://git./linux/kernel/git/gregkh/staging

Pull staging/iio fixes from Greg KH:
 "Here are some Staging and IIO driver fixes for 4.13-rc5.

  Nothing major, just a number of small fixes for reported issues. All
  of these have been in linux-next for a while now with no reported
  issues. Full details are in the shortlog"

* tag 'staging-4.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: comedi: comedi_fops: do not call blocking ops when !TASK_RUNNING
  iio: aspeed-adc: wait for initial sequence.
  iio: accel: bmc150: Always restore device to normal mode after suspend-resume
  staging:iio:resolver:ad2s1210 fix negative IIO_ANGL_VEL read
  iio: adc: axp288: Fix the GPADC pin reading often wrongly returning 0
  iio: adc: vf610_adc: Fix VALT selection value for REFSEL bits
  iio: accel: st_accel: add SPI-3wire support
  iio: adc: Revert "axp288: Drop bogus AXP288_ADC_TS_PIN_CTRL register modifications"
  iio: adc: sun4i-gpadc-iio: fix unbalanced irq enable/disable
  iio: pressure: st_pressure_core: disable multiread by default for LPS22HB
  iio: light: tsl2563: use correct event code

Merge tag 'usb-4.13-rc5' of git://git./linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are a number of small USB driver fixes and new device ids for
  4.13-rc5. There is the usual gadget driver fixes, some new quirks for
  "messy" hardware, and some new device ids.

  All have been in linux-next with no reported issues"

* tag 'usb-4.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: serial: pl2303: add new ATEN device id
  usb: quirks: Add no-lpm quirk for Moshi USB to Ethernet Adapter
  USB: Check for dropped connection before switching to full speed
  usb:xhci:Add quirk for Certain failing HP keyboard on reset after resume
  usb: renesas_usbhs: gadget: fix unused-but-set-variable warning
  usb: renesas_usbhs: Fix UGCTRL2 value for R-Car Gen3
  usb: phy: phy-msm-usb: Fix usage of devm_regulator_bulk_get()
  usb: gadget: udc: renesas_usb3: Fix usb_gadget_giveback_request() calling
  usb: dwc3: gadget: Correct ISOC DATA PIDs for short packets
  USB: serial: option: add D-Link DWM-222 device ID
  usb: musb: fix tx fifo flush handling again
  usb: core: unlink urbs from the tail of the endpoint's urb_list
  usb-storage: fix deadlock involving host lock and scsi_done
  uas: Add US_FL_IGNORE_RESIDUE for Initio Corporation INIC-3069
  USB: hcd: Mark secondary HCD as dead if the primary one died
  USB: serial: cp210x: add support for Qivicon USB ZigBee dongle

Merge tag 'for-linus-20170812' of git://git.infradead.org/linux-mtd

Pull another MTD fix from Brian Norris:
 "An mtdblock regression occurred in -rc1 (all writes were broken!), in
  the process of some block subsystem refactoring. Noticed and fixed
  last week, but I'm a little slow on the uptake"

* tag 'for-linus-20170812' of git://git.infradead.org/linux-mtd:
  mtd: blkdevs: Fix mtd block write failure

mtd: blkdevs: Fix mtd block write failure

All the MTD block write requests are failing with
following error messages

    mkfs.ext4  /dev/mtdblock0

    print_req_error: I/O error, dev mtdblock0, sector 0
    Buffer I/O error on dev mtdblock0, logical block 0,
    lost async page write

The control is going to default case after block write request
because of missing return.

Fixes: commit 2a842acab109 ("block: introduce new block status code type")
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

Merge git://git./linux/kernel/git/nab/target-pending

Pull SCSI target fixes from Nicholas Bellinger:
 "The highlights include:

   - Fix iscsi-target payload memory leak during
     ISCSI_FLAG_TEXT_CONTINUE (Varun Prakash)

   - Fix tcm_qla2xxx incorrect use of tcm_qla2xxx_free_cmd during ABORT
     (Pascal de Bruijn + Himanshu Madhani + nab)

   - Fix iscsi-target long-standing issue with parallel delete of a
     single network portal across multiple target instances (Gary Guo +
     nab)

   - Fix target dynamic se_node GPF during uncached shutdown regression
     (Justin Maggard + nab)"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: Fix node_acl demo-mode + uncached dynamic shutdown regression
  iscsi-target: Fix iscsi_np reset hung task during parallel delete
  qla2xxx: Fix incorrect tcm_qla2xxx_free_cmd use during TMR ABORT (v2)
  cxgbit: fix sg_nents calculation
  iscsi-target: fix invalid flags in text response
  iscsi-target: fix memory leak in iscsit_setup_text_cmd()
  cxgbit: add missing __kfree_skb()
  tcmu: free old string on reconfig
  tcmu: Fix possible to/from address overflow when doing the memcpy

Merge tag 'for-linus-4.13b-rc5-tag' of git://git./linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "Some fixes for Xen:

   - a fix for a regression introduced in 4.13 for a Xen HVM-guest
     configured with KASLR

   - a fix for a possible deadlock in the xenbus driver when booting the
     system

   - a fix for lost interrupts in Xen guests"

* tag 'for-linus-4.13b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/events: Fix interrupt lost during irq_disable and irq_enable
  xen: avoid deadlock in xenbus
  xen: fix hvm guest with kaslr enabled
  xen: split up xen_hvm_init_shared_info()
  x86: provide an init_mem_mapping hypervisor hook

Merge tag 'nfs-for-4.13-5' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client fixes from Anna Schumaker:
 "A few more NFS client bugfixes from me for rc5.

  Dros has a stable fix for flexfiles to prevent leaking the
  nfs4_ff_ds_version arrays when freeing a layout, Trond fixed a
  potential recovery loop situation with the TEST_STATEID operation, and
  Christoph fixed up the pNFS blocklayout Kconfig options to prevent
  unsafe use with kernels that don't have large block device support.
  Summary:

  Stable fix:
   - fix leaking nfs4_ff_ds_version array

  Other fixes:
   - improve TEST_STATEID OLD_STATEID handling to prevent recovery loop

   - require 64-bit sector_t for pNFS blocklayout to prevent 32-bit
     compile errors"

* tag 'nfs-for-4.13-5' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  pnfs/blocklayout: require 64-bit sector_t
  NFSv4: Ignore NFS4ERR_OLD_STATEID in nfs41_check_open_stateid()
  nfs/flexfiles: fix leak of nfs4_ff_ds_version arrays

Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A set of fixes that should go into this series. This contains:

   - Fix from Bart for blk-mq requeue queue running, preventing a
     continued loop of run/restart.

   - Fix for a bio/blk-integrity issue, in two parts. One from
     Christoph, fixing where verification happens, and one from Milan,
     for a NULL profile.

   - NVMe pull request, most of the changes being for nvme-fc, but also
     a few trivial core/pci fixes"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: fix directive command numd calculation
  nvme: fix nvme reset command timeout handling
  nvme-pci: fix CMB sysfs file removal in reset path
  lpfc: support nvmet_fc defer_rcv callback
  nvmet_fc: add defer_req callback for deferment of cmd buffer return
  nvme: strip trailing 0-bytes in wwid_show
  block: Make blk_mq_delay_kick_requeue_list() rerun the queue at a quiet time
  bio-integrity: only verify integrity on the lowest stacked driver
  bio-integrity: Fix regression if profile verify_fn is NULL

Merge tag 'mmc-v4.13-rc4' of git://git./linux/kernel/git/ulfh/mmc

Pull MMC fixes from Ulf Hansson:
 "MMC core:

   - fix lockdep splat when removing mmc_block module

   - fix the logic for setting eMMC HS400ES signal voltage

  MMC host:

   - omap_hsmmc: add CMD23 capability to fix -EIO errors"

* tag 'mmc-v4.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: block: fix lockdep splat when removing mmc_block module
  mmc: mmc: correct the logic for setting HS400ES signal voltage
  mmc: host: omap_hsmmc: Add CMD23 capability to omap_hsmmc driver

Merge tag 'fbdev-v4.13-rc5' of git://github.com/bzolnier/linux

Pull fbdev fixes from Bartlomiej Zolnierkiewicz:

 - allow user to disable write combined mapping in efifb driver (Dave
   Airlie)

 - fix use after free bugs on driver removal in imxfb driver (Dan
   Carpenter)

 - fix unused variable warning in omapfb driver (Arnd Bergmann)

* tag 'fbdev-v4.13-rc5' of git://github.com/bzolnier/linux:
  efifb: allow user to disable write combined mapping.
  fbdev: omapfb: remove unused variable
  video: fbdev: imxfb: use after free in imxfb_remove()

Merge branch 'for-linus' of git://git./linux/kernel/git/mszeredi/fuse

Pull fuse fixes from Miklos Szeredi:
 "Fix a few bugs in fuse"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: set mapping error in writepage_locked when it fails
  fuse: Dont call set_page_dirty_lock() for ITER_BVEC pages for async_dio
  fuse: initialize the flock flag in fuse_file on allocation

Merge tag 'iommu-fixes-v4.13-rc4' of git://git./linux/kernel/git/joro/iommu

Pull IOMMU fix from Joerg Roedel:
 "Fix a NULL-pointer dereference in arm_smmu_add_device"

* tag 'iommu-fixes-v4.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/arm-smmu: fix null-pointer dereference in arm_smmu_add_device

pnfs/blocklayout: require 64-bit sector_t

The blocklayout code does not compile cleanly for a 32-bit sector_t,
and also has no reliable checks for devices sizes, which makes it
unsafe to use with a kernel that doesn't support large block devices.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 5c83746a0cf2 ("pnfs/blocklayout: in-kernel GETDEVICEINFO XDR parsing")
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Merge tag 'powerpc-4.13-6' of git://git./linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "All fixes for code that went in this cycle.

   - a revert of an optimisation to the syscall exit path, which could
     lead to an oops on either older machines or machines with > 1TB of
     memory

   - disable some deep idle states if the firmware configuration for
     them fails

   - re-enable HARD/SOFT lockup detectors in defconfigs after a Kconfig
     change

   - six fairly small patches fixing bugs in our new watchdog code

  Thanks to: Gautham R Shenoy, Nicholas Piggin"

* tag 'powerpc-4.13-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/watchdog: add locking around init/exit functions
  powerpc/watchdog: Fix marking of stuck CPUs
  powerpc/watchdog: Fix final-check recovered case
  powerpc/watchdog: Moderate touch_nmi_watchdog overhead
  powerpc/watchdog: Improve watchdog lock primitive
  powerpc: NMI IPI improve lock primitive
  powerpc/configs: Re-enable HARD/SOFT lockup detectors
  powerpc/powernv/idle: Disable LOSE_FULL_CONTEXT states when stop-api fails
  Revert "powerpc/64: Avoid restore_math call if possible in syscall exit"

iommu/arm-smmu: fix null-pointer dereference in arm_smmu_add_device

Commit c54451a "iommu/arm-smmu: Fix the error path in arm_smmu_add_device"
removed fwspec assignment in legacy_binding path as redundant which is
wrong. It needs to be updated after fwspec initialisation in
arm_smmu_register_legacy_master() as it is dereferenced later. Without
this there is a NULL-pointer dereference panic during boot on some hosts.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

xen/events: Fix interrupt lost during irq_disable and irq_enable

Here is a device has xen-pirq-MSI interrupt. Dom0 might lost interrupt
during driver irq_disable/irq_enable. Here is the scenario,
 1. irq_disable -> disable_dynirq -> mask_evtchn(irq channel)
 2. dev interrupt raised by HW and Xen mark its evtchn as pending
 3. irq_enable -> startup_pirq -> eoi_pirq ->
    clear_evtchn(channel of irq) -> clear pending status
 4. consume_one_event process the irq event without pending bit assert
    which result in interrupt lost once
 5. No HW interrupt raising anymore.

Now use enable_dynirq for enable_pirq of xen_pirq_chip to remove
eoi_pirq when irq_enable.

Signed-off-by: Liu Shuo <shuo.a.liu@intel.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

xen: avoid deadlock in xenbus

When starting the xenwatch thread a theoretical deadlock situation is
possible:

xs_init() contains:

    task = kthread_run(xenwatch_thread, NULL, "xenwatch");
    if (IS_ERR(task))
        return PTR_ERR(task);
    xenwatch_pid = task->pid;

And xenwatch_thread() does:

    mutex_lock(&xenwatch_mutex);
    ...
    event->handle->callback();
    ...
    mutex_unlock(&xenwatch_mutex);

The callback could call unregister_xenbus_watch() which does:

    ...
    if (current->pid != xenwatch_pid)
        mutex_lock(&xenwatch_mutex);
    ...

In case a watch is firing before xenwatch_pid could be set and the
callback of that watch unregisters a watch, then a self-deadlock would
occur.

Avoid this by setting xenwatch_pid in xenwatch_thread().

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Merge branch 'nvme-4.13' of git://git.infradead.org/nvme into for-linus

Pull NVMe fixes from Christoph:

"A few more small fixes - the fc/lpfc update is the biggest by far."

xen: fix hvm guest with kaslr enabled

A Xen HVM guest running with KASLR enabled will die rather soon today
because the shared info page mapping is using va() too early. This was
introduced by commit a5d5f328b0e2baa5ee7c119fd66324eb79eeeb66 ("xen:
allocate page for shared info page from low memory").

In order to fix this use early_memremap() to get a temporary virtual
address for shared info until va() can be used safely.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>

xen: split up xen_hvm_init_shared_info()

Instead of calling xen_hvm_init_shared_info() on boot and resume split
it up into a boot time function searching for the pfn to use and a
mapping function doing the hypervisor mapping call.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>

x86: provide an init_mem_mapping hypervisor hook

Provide a hook in hypervisor_x86 called after setting up initial
memory mapping.

This is needed e.g. by Xen HVM guests to map the hypervisor shared
info page.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>

fuse: set mapping error in writepage_locked when it fails

This ensures that we see errors on fsync when writeback fails.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

Merge tag 'drm-fixes-for-v4.13-rc5' of git://people.freedesktop.org/~airlied/linux

Pull drm fixes from Dave Airlie:
 "Nothing too earth shattering here, it just seems like lots of little
  things all over the place.

  msm has probably the larger amount of changes, but they all seem fine,
  otherwise, some rockchip, i915, etnaviv and exynos fixes, along with
  one nouveau regression fix for some older GPUs"

* tag 'drm-fixes-for-v4.13-rc5' of git://people.freedesktop.org/~airlied/linux: (35 commits)
  drm/nouveau/disp/nv04: avoid creation of output paths
  drm: make DRM_STM default n
  drm/exynos: forbid creating framebuffers from too small GEM buffers
  drm/etnaviv: Fix off-by-one error in reloc checking
  drm/i915: fix backlight invert for non-zero minimum brightness
  drm/i915/shrinker: Wrap need_resched() inside preempt-disable
  drm/i915/perf: fix flex eu registers programming
  drm/i915: Fix out-of-bounds array access in bdw_load_gamma_lut
  drm/i915/gvt: Change the max length of mmio_reg_rw from 4 to 8
  drm/i915/gvt: Initialize MMIO Block with HW state
  drm/rockchip: vop: report error when check resource error
  drm/rockchip: vop: round_up pitches to word align
  drm/rockchip: vop: fix NV12 video display error
  drm/rockchip: vop: fix iommu page fault when resume
  drm/i915/gvt: clean workload queue if error happened
  drm/i915/gvt: change resetting to resetting_eng
  drm/msm: gpu: don't abuse dma_alloc for non-DMA allocations
  drm/msm: gpu: call qcom_mdt interfaces only for ARCH_QCOM
  drm/msm/adreno: Prevent unclocked access when retrieving timestamps
  drm/msm: Remove __user from __u64 data types
  ...

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
  ...

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>

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>

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: c7ab0d2fdc84 ("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>

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: 779750d20b93 ("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>

mm/balloon_compaction.c: don't zero ballooned pages

Revert commit bb01b64cfab7 ("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: bb01b64cfab7 ("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>

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>

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>

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>

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>

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>

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 b0943d61b8fa ("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>

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>

mm: migrate: prevent racy access to tlb_flush_pending

Patch series "fixes of TLB batching races", v6.

It turns out that Linux TLB batching mechanism suffers from various
races.  Races that are caused due to batching during reclamation were
recently handled by Mel and this patch-set deals with others.  The more
fundamental issue is that concurrent updates of the page-tables allow
for TLB flushes to be batched on one core, while another core changes
the page-tables.  This other core may assume a PTE change does not
require a flush based on the updated PTE value, while it is unaware that
TLB flushes are still pending.

This behavior affects KSM (which may result in memory corruption) and
MADV_FREE and MADV_DONTNEED (which may result in incorrect behavior).  A
proof-of-concept can easily produce the wrong behavior of MADV_DONTNEED.
Memory corruption in KSM is harder to produce in practice, but was
observed by hacking the kernel and adding a delay before flushing and
replacing the KSM page.

Finally, there is also one memory barrier missing, which may affect
architectures with weak memory model.

This patch (of 7):

Setting and clearing mm->tlb_flush_pending can be performed by multiple
threads, since mmap_sem may only be acquired for read in
task_numa_work().  If this happens, tlb_flush_pending might be cleared
while one of the threads still changes PTEs and batches TLB flushes.

This can lead to the same race between migration and
change_protection_range() that led to the introduction of
tlb_flush_pending.  The result of this race was data corruption, which
means that this patch also addresses a theoretically possible data
corruption.

An actual data corruption was not observed, yet the race was was
confirmed by adding assertion to check tlb_flush_pending is not set by
two threads, adding artificial latency in change_protection_range() and
using sysctl to reduce kernel.numa_balancing_scan_delay_ms.

Link: http://lkml.kernel.org/r/20170802000818.4760-2-namit@vmware.com
Fixes: 20841405940e ("mm: fix TLB flush race between migration, and
change_protection_range")
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andrea Arcangeli <aarcange@redhat.com>
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@techsingularity.net>
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>

fault-inject: fix wrong should_fail() decision in task context

Commit 1203c8e6fb0a ("fault-inject: simplify access check for fail-nth")
unintentionally broke a conditional statement in should_fail().  Any
faults are not injected in the task context by the change when the
systematic fault injection is not used.

This change restores to the previous correct behaviour.

Link: http://lkml.kernel.org/r/1501633700-3488-1-git-send-email-akinobu.mita@gmail.com
Fixes: 1203c8e6fb0a ("fault-inject: simplify access check for fail-nth")
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Tested-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

test_kmod: fix small memory leak on filesystem tests

The break was in the wrong place so file system tests don't work as
intended, leaking memory at each test switch.

[mcgrof@kernel.org: massaged commit subject, noted memory leak issue without the fix]
Link: http://lkml.kernel.org/r/20170802211450.27928-6-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Reported-by: David Binderman <dcb314@hotmail.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

test_kmod: fix the lock in register_test_dev_kmod()

We accidentally just drop the lock twice instead of taking it and then
releasing it.  This isn't a big issue unless you are adding more than
one device to test on, and the kmod.sh doesn't do that yet, however this
obviously is the correct thing to do.

[mcgrof@kernel.org: massaged subject, explain what happens]
Link: http://lkml.kernel.org/r/20170802211450.27928-5-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

test_kmod: fix bug which allows negative values on two config options

Parsing with kstrtol() enables values to be negative, and we failed to
check for negative values when parsing with test_dev_config_update_uint_sync()
or test_dev_config_update_uint_range().

test_dev_config_update_uint_range() has a minimum check though so an
issue is not present there.  test_dev_config_update_uint_sync() is only
used for the number of threads to use (config_num_threads_store()), and
indeed this would fail with an attempt for a large allocation.

Although the issue is only present in practice with the first fix both
by using kstrtoul() instead of kstrtol().

Link: http://lkml.kernel.org/r/20170802211450.27928-4-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

test_kmod: fix spelling mistake: "EMTPY" -> "EMPTY"

Trivial fix to spelling mistake in snprintf text

[mcgrof@kernel.org: massaged commit message]
Link: http://lkml.kernel.org/r/20170802211450.27928-3-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michal Marek <mmarek@suse.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

userfaultfd: hugetlbfs: remove superfluous page unlock in VM_SHARED case

huge_add_to_page_cache->add_to_page_cache implicitly unlocks the page
before returning in case of errors.

The error returned was -EEXIST by running UFFDIO_COPY on a non-hole
offset of a VM_SHARED hugetlbfs mapping.  It was an userland bug that
triggered it and the kernel must cope with it returning -EEXIST from
ioctl(UFFDIO_COPY) as expected.

  page dumped because: VM_BUG_ON_PAGE(!PageLocked(page))
  kernel BUG at mm/filemap.c:964!
  invalid opcode: 0000 [#1] SMP
  CPU: 1 PID: 22582 Comm: qemu-system-x86 Not tainted 4.11.11-300.fc26.x86_64 #1
  RIP: unlock_page+0x4a/0x50
  Call Trace:
    hugetlb_mcopy_atomic_pte+0xc0/0x320
    mcopy_atomic+0x96f/0xbe0
    userfaultfd_ioctl+0x218/0xe90
    do_vfs_ioctl+0xa5/0x600
    SyS_ioctl+0x79/0x90
    entry_SYSCALL_64_fastpath+0x1a/0xa9

Link: http://lkml.kernel.org/r/20170802165145.22628-2-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Alexey Perevalov <a.perevalov@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: ratelimit PFNs busy info message

The RDMA subsystem can generate several thousand of these messages per
second eventually leading to a kernel crash.  Ratelimit these messages
to prevent this crash.

Doug said:
 "I've been carrying a version of this for several kernel versions. I
  don't remember when they started, but we have one (and only one) class
  of machines: Dell PE R730xd, that generate these errors. When it
  happens, without a rate limit, we get rcu timeouts and kernel oopses.
  With the rate limit, we just get a lot of annoying kernel messages but
  the machine continues on, recovers, and eventually the memory
  operations all succeed"

And:
 "> Well... why are all these EBUSY's occurring? It sounds inefficient
  > (at least) but if it is expected, normal and unavoidable then
  > perhaps we should just remove that message altogether?

  I don't have an answer to that question. To be honest, I haven't
  looked real hard. We never had this at all, then it started out of the
  blue, but only on our Dell 730xd machines (and it hits all of them),
  but no other classes or brands of machines. And we have our 730xd
  machines loaded up with different brands and models of cards (for
  instance one dedicated to mlx4 hardware, one for qib, one for mlx5, an
  ocrdma/cxgb4 combo, etc), so the fact that it hit all of the machines
  meant it wasn't tied to any particular brand/model of RDMA hardware.
  To me, it always smelled of a hardware oddity specific to maybe the
  CPUs or mainboard chipsets in these machines, so given that I'm not an
  mm expert anyway, I never chased it down.

  A few other relevant details: it showed up somewhere around 4.8/4.9 or
  thereabouts. It never happened before, but the prinkt has been there
  since the 3.18 days, so possibly the test to trigger this message was
  changed, or something else in the allocator changed such that the
  situation started happening on these machines?

  And, like I said, it is specific to our 730xd machines (but they are
  all identical, so that could mean it's something like their specific
  ram configuration is causing the allocator to hit this on these
  machine but not on other machines in the cluster, I don't want to say
  it's necessarily the model of chipset or CPU, there are other bits of
  identicalness between these machines)"

Link: http://lkml.kernel.org/r/499c0f6cc10d6eb829a67f2a4d75b4228a9b356e.1501695897.git.jtoppins@redhat.com
Signed-off-by: Jonathan Toppins <jtoppins@redhat.com>
Reviewed-by: Doug Ledford <dledford@redhat.com>
Tested-by: Doug Ledford <dledford@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: fix global NR_SLAB_.*CLAIMABLE counter reads

As Tetsuo points out:
 "Commit 385386cff4c6 ("mm: vmstat: move slab statistics from zone to
  node counters") broke "Slab:" field of /proc/meminfo . It shows nearly
  0kB"

In addition to /proc/meminfo, this problem also affects the slab
counters OOM/allocation failure info dumps, can cause early -ENOMEM from
overcommit protection, and miscalculate image size requirements during
suspend-to-disk.

This is because the patch in question switched the slab counters from
the zone level to the node level, but forgot to update the global
accessor functions to read the aggregate node data instead of the
aggregate zone data.

Use global_node_page_state() to access the global slab counters.

Fixes: 385386cff4c6 ("mm: vmstat: move slab statistics from zone to node counters")
Link: http://lkml.kernel.org/r/20170801134256.5400-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Stefan Agner <stefan@agner.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'pci-v4.13-fixes-2' of git://git./linux/kernel/git/helgaas/pci

Pull PCI fix from Bjorn Helgaas:
 "Work around Renesas uPD72020x 32-bit DMA issue"

* tag 'pci-v4.13-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  xhci: Reset Renesas uPD72020x USB controller for 32-bit DMA issue
  PCI: Add pci_reset_function_locked()

thunderbolt: Do not enumerate more ports from DROM than the controller has

Some Alpine Ridge LP DROMs (there might be others) erroneusly list more
ports than the controller actually has. Most probably because DROM of
the full Dual/Single port Thunderbolt controller was reused for LP
version. The current DROM parser does not check the upper bound thus it
leads to crash when sw->ports[] is accessed over bounds:

 BUG: unable to handle kernel NULL pointer dereference at 00000000000002ec
 IP: tb_drom_read+0x383/0x890 [thunderbolt]
 PGD 0
 P4D 0
 Oops: 0000 [#1] SMP
 CPU: 3 PID: 12248 Comm: systemd-udevd Not tainted 4.13.0-rc1-next-20170719 #1
 Hardware name: LENOVO 20HF000YGE/20HF000YGE, BIOS N1WET32W (1.11 ) 05/23/2017
 task: ffff8a293e4bcd80 task.stack: ffffa698027a8000
 RIP: 0010:tb_drom_read+0x383/0x890 [thunderbolt]
 RSP: 0018:ffffa698027ab990 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: ffff8a2940af7800 RCX: 0000000000000000
 RDX: ffff8a2940ebb400 RSI: 0000000000000000 RDI: ffffa698027ab9a0
 RBP: ffffa698027ab9d0 R08: 0000000000000001 R09: 0000000000000002
 R10: ffff8a2940ebb5b0 R11: 0000000000000000 R12: ffff8a293bfa968c
 R13: 000000000000002c R14: 0000000000000056 R15: 0000000000000056
 FS:  00007f0a945a38c0(0000) GS:ffff8a2961580000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00000000000002ec CR3: 000000043e785000 CR4: 00000000003606e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  tb_switch_add+0x9d/0x730 [thunderbolt]
  ? tb_switch_alloc+0x3cd/0x4d0 [thunderbolt]
  icm_start+0x5a/0xa0 [thunderbolt]
  tb_domain_add+0xc3/0xf0 [thunderbolt]
  nhi_probe+0x19e/0x310 [thunderbolt]
  local_pci_probe+0x42/0xa0
  pci_device_probe+0x18d/0x1a0
  driver_probe_device+0x2ff/0x450
  __driver_attach+0xa4/0xe0
  ? driver_probe_device+0x450/0x450
  bus_for_each_dev+0x6e/0xb0
  driver_attach+0x1e/0x20
  bus_add_driver+0x1d0/0x270
  ? 0xffffffffc0bbb000
  driver_register+0x60/0xe0
  ? 0xffffffffc0bbb000
  __pci_register_driver+0x4c/0x50
  nhi_init+0x28/0x1000 [thunderbolt]
  do_one_initcall+0x50/0x190
  ? __vunmap+0x81/0xb0
  ? _cond_resched+0x1a/0x50
  ? kmem_cache_alloc_trace+0x15f/0x1c0
  ? do_init_module+0x27/0x1e9
  do_init_module+0x5f/0x1e9
  load_module+0x24e7/0x2a60
  ? vfs_read+0x115/0x130
  SYSC_finit_module+0xfc/0x120
  ? SYSC_finit_module+0xfc/0x120
  SyS_finit_module+0xe/0x10
  do_syscall_64+0x67/0x170
  entry_SYSCALL64_slow_path+0x25/0x25

Fix this by making sure we only enumerate DROM port entries the hardware
actually has.

Reported-by: Christian Kellner <ckellner@redhat.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Christian Kellner <ckellner@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: exclude device from suspend direct complete optimization

MEI device performs link reset during system suspend sequence.
The link reset cannot be performed while device is in
runtime suspend state. The resume sequence is bypassed with
suspend direct complete optimization,so the optimization should be
disabled for mei devices.

Fixes:
 [  192.940537] Restarting tasks ...
 [  192.940610] PGI is not set
 [  192.940619] ------------[ cut here ]------------ [  192.940623]
 WARNING: CPU: 0
 me.c:653 mei_me_pg_exit_sync+0x351/0x360 [  192.940624] Modules
 linked
 in:
 [  192.940627] CPU: 0 PID: 1661 Comm: kworker/0:3 Not tainted
 4.13.0-rc2+
 #2 [  192.940628] Hardware name: Dell Inc. XPS 13 9343/0TM99H, BIOS
 A11
 12/08/2016 [  192.940630] Workqueue: pm pm_runtime_work <snip> [
 192.940642] Call Trace:
 [  192.940646]  ? pci_pme_active+0x1de/0x1f0 [  192.940649]  ?
 pci_restore_standard_config+0x50/0x50
 [  192.940651]  ? kfree+0x172/0x190
 [  192.940653]  ? kfree+0x172/0x190
 [  192.940655]  ? pci_restore_standard_config+0x50/0x50
 [  192.940663]  mei_me_pm_runtime_resume+0x3f/0xc0
 [  192.940665]  pci_pm_runtime_resume+0x7a/0xa0 [  192.940667]
 __rpm_callback+0xb9/0x1e0 [  192.940668]  ?
 preempt_count_add+0x6d/0xc0 [  192.940670]  rpm_callback+0x24/0x90 [
 192.940672]  ? pci_restore_standard_config+0x50/0x50
 [  192.940674]  rpm_resume+0x4e8/0x800 [  192.940676]
 pm_runtime_work+0x55/0xb0 [  192.940678]
 process_one_work+0x184/0x3e0 [  192.940680]
 worker_thread+0x4d/0x3a0 [ 192.940681]  ?
 preempt_count_sub+0x9b/0x100 [  192.940683]
 kthread+0x122/0x140 [  192.940684]  ? process_one_work+0x3e0/0x3e0 [
 192.940685]  ? __kthread_create_on_node+0x1a0/0x1a0
 [  192.940688]  ret_from_fork+0x27/0x40 [  192.940690] Code: 96 3a
 9e ff 48 8b 7d 98 e8 cd 21 58 00 83 bb bc 01 00 00
 04 0f 85 40 fe ff ff e9 41 fe ff ff 48 c7 c7 5f 04 99 96 e8 93 6b 9f
 ff <0f> ff e9 5d fd ff ff e8 33 fe 99 ff 0f 1f 00 0f 1f 44 00 00 55
 [  192.940719] ---[ end trace
 a86955597774ead8 ]--- [  192.942540] done.

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: avoid invalid fallback aborts by using killable wait

Commit 0cb64249ca500 ("firmware_loader: abort request if wait_for_completion
is interrupted") added via 4.0 added support to abort the fallback mechanism
when a signal was detected and wait_for_completion_interruptible() returned
-ERESTARTSYS -- for instance when a user hits CTRL-C. The abort was overly
*too* effective.

When a child process terminates (successful or not) the signal SIGCHLD can
be sent to the parent process which ran the child in the background and
later triggered a sync request for firmware through a sysfs interface which
relies on the fallback mechanism. This signal in turn can be recieved by the
interruptible wait we constructed on firmware_class and detects it as an
abort *before* userspace could get a chance to write the firmware. Upon
failure -EAGAIN is returned, so userspace is also kept in the dark about
exactly what happened.

We can reproduce the issue with the fw_fallback.sh selftest:

Before this patch:
$ sudo tools/testing/selftests/firmware/fw_fallback.sh
...
tools/testing/selftests/firmware/fw_fallback.sh: error - sync firmware request cancelled due to SIGCHLD

After this patch:
$ sudo tools/testing/selftests/firmware/fw_fallback.sh
...
tools/testing/selftests/firmware/fw_fallback.sh: SIGCHLD on sync ignored as expected

Fix this by making the wait killable -- only killable by SIGKILL (kill -9).
We loose the ability to allow userspace to cancel a write with CTRL-C
(SIGINT), however its been decided the compromise to require SIGKILL is
worth the gains.

Chances of this issue occuring are low due to the number of drivers upstream
exclusively relying on the fallback mechanism for firmware (2 drivers),
however this is observed in the field with custom drivers with sysfs
triggers to load firmware. Only distributions relying on the fallback
mechanism are impacted as well. An example reported issue was on Android,
as follows:

1) Android init (pid=1) fork()s (say pid=42) [this child process is totally
   unrelated to firmware loading, it could be sleep 2; for all we care ]
2) Android init (pid=1) does a write() on a (driver custom) sysfs file which
   ends up calling request_firmware() kernel side
3) The firmware loading fallback mechanism is used, the request is sent to
   userspace and pid 1 waits in the kernel on wait_*
4) before firmware loading completes pid 42 dies (for any reason, even
   normal termination)
5) Kernel delivers SIGCHLD to pid=1 to tell it a child has died, which
   causes -ERESTARTSYS to be returned from wait_*
6) The kernel's wait aborts and return -EAGAIN for the
   request_firmware() caller.

Cc: stable <stable@vger.kernel.org> # 4.0
Fixes: 0cb64249ca500 ("firmware_loader: abort request if wait_for_completion is interrupted")
Suggested-by: "Eric W. Biederman" <ebiederm@xmission.com>
Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Martin Fuzzey <mfuzzey@parkeon.com>
Reported-by: Martin Fuzzey <mfuzzey@parkeon.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: fix batched requests - send wake up on failure on direct lookups

Fix batched requests from waiting forever on failure.

The firmware API batched requests feature has been broken since the API call
request_firmware_direct() was introduced on commit bba3a87e982ad ("firmware:
Introduce request_firmware_direct()"), added on v3.14 *iff* the firmware
being requested was not present in *certain kernel builds* [0].

When no firmware is found the worker which goes on to finish never informs
waiters queued up of this, so any batched request will stall in what seems
to be forever (MAX_SCHEDULE_TIMEOUT). Sadly, a reboot will also stall, as
the reboot notifier was only designed to kill custom fallback workers. The
issue seems to the user as a type of soft lockup, what *actually* happens
underneath the hood is a wait call which never completes as we failed to
issue a completion on error.

For device drivers with optional firmware schemes (ie, Intel iwlwifi, or
Netronome -- even though it uses request_firmware() and not
request_firmware_direct()), this could mean that when you boot a system with
multiple cards the firmware will seem to never load on the system, or that
the card is just not responsive even the driver initialization. Due to
differences in scheduling possible this should not always trigger --
one would need to to ensure that multiple requests are in place at the
right time for this to work, also release_firmware() must not be called
prior to any other incoming request. The complexity may not be worth
supporting batched requests in the future given the wait mechanism is
only used also for the fallback mechanism. We'll keep it for now and
just fix it.

Its reported that at least with the Intel WiFi cards on one system this
issue was creeping up 50% of the boots [0].

Before this commit batched requests testing revealed:
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n
CONFIG_FW_LOADER_USER_HELPER=y

Most common Linux distribution setup.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     FAIL                OK
request_firmware_direct()              FAIL                OK
request_firmware_nowait(uevent=true)   FAIL                OK
request_firmware_nowait(uevent=false)  FAIL                OK
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n
CONFIG_FW_LOADER_USER_HELPER=n

Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     FAIL                OK
request_firmware_direct()              FAIL                OK
request_firmware_nowait(uevent=true)   FAIL                OK
request_firmware_nowait(uevent=false)  FAIL                OK
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
CONFIG_FW_LOADER_USER_HELPER=y

Google Android setup.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     OK                  OK
request_firmware_direct()              FAIL                OK
request_firmware_nowait(uevent=true)   OK                  OK
request_firmware_nowait(uevent=false)  OK                  OK
============================================================================

Ater this commit batched testing results:
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n
CONFIG_FW_LOADER_USER_HELPER=y

Most common Linux distribution setup.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     OK                  OK
request_firmware_direct()              OK                  OK
request_firmware_nowait(uevent=true)   OK                  OK
request_firmware_nowait(uevent=false)  OK                  OK
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n
CONFIG_FW_LOADER_USER_HELPER=n

Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     OK                  OK
request_firmware_direct()              OK                  OK
request_firmware_nowait(uevent=true)   OK                  OK
request_firmware_nowait(uevent=false)  OK                  OK
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
CONFIG_FW_LOADER_USER_HELPER=y

Google Android setup.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     OK                  OK
request_firmware_direct()              OK                  OK
request_firmware_nowait(uevent=true)   OK                  OK
request_firmware_nowait(uevent=false)  OK                  OK
============================================================================

[0] https://bugzilla.kernel.org/show_bug.cgi?id=195477

Cc: stable <stable@vger.kernel.org> # v3.14
Fixes: bba3a87e982ad ("firmware: Introduce request_firmware_direct()"
Reported-by: Nicolas <nbroeking@me.com>
Reported-by: John Ewalt <jewalt@lgsinnovations.com>
Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: fix batched requests - wake all waiters

The firmware cache mechanism serves two purposes, the secondary purpose is
not well documented nor understood. This fixes a regression with the
secondary purpose of the firmware cache mechanism: batched requests on
successful lookups. Without this fix *any* time a batched request is
triggered, secondary requests for which the batched request mechanism
was designed for will seem to last forver and seem to never return.
This issue is present for all kernel builds possible, and a hard reset
is required.

The firmware cache is used for:

1) Addressing races with file lookups during the suspend/resume cycle
   by keeping firmware in memory during the suspend/resume cycle

2) Batched requests for the same file rely only on work from the first file
   lookup, which keeps the firmware in memory until the last
   release_firmware() is called

Batched requests *only* take effect if secondary requests come in prior to
the first user calling release_firmware(). The devres name used for the
internal firmware cache is used as a hint other pending requests are
ongoing, the firmware buffer data is kept in memory until the last user of
the buffer calls release_firmware(), therefore serializing requests and
delaying the release until all requests are done.

Batched requests wait for a wakup or signal so we can rely on the first file
fetch to write to the pending secondary requests. Commit 5b029624948d
("firmware: do not use fw_lock for fw_state protection") ported the firmware
API to use swait, and in doing so failed to convert complete_all() to
swake_up_all() -- it used swake_up(), loosing the ability for *some* batched
requests to take effect.

We *could* fix this by just using swake_up_all() *but* swait is now known
to be very special use case, so its best to just move away from it. So we
just go back to using completions as before commit 5b029624948d ("firmware:
do not use fw_lock for fw_state protection") given this was using
complete_all().

Without this fix it has been reported plugging in two Intel 6260 Wifi cards
on a system will end up enumerating the two devices only 50% of the time
[0]. The ported swake_up() should have actually handled the case with two
devices, however, *if more than two cards are used* the swake_up() would
not have sufficed. This change is only part of the required fixes for
batched requests. Another fix is provided in the next patch.

This particular change should fix the cases where more than three requests
with the same firmware name is used, otherwise batched requests will wait
for MAX_SCHEDULE_TIMEOUT and just timeout eventually.

Below is a summary of tests triggering batched requests on different
kernel builds.

Before this patch:
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n
CONFIG_FW_LOADER_USER_HELPER=y

Most common Linux distribution setup.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     FAIL                FAIL
request_firmware_direct()              FAIL                FAIL
request_firmware_nowait(uevent=true)   FAIL                FAIL
request_firmware_nowait(uevent=false)  FAIL                FAIL
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n
CONFIG_FW_LOADER_USER_HELPER=n

Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     FAIL                FAIL
request_firmware_direct()              FAIL                FAIL
request_firmware_nowait(uevent=true)   FAIL                FAIL
request_firmware_nowait(uevent=false)  FAIL                FAIL
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
CONFIG_FW_LOADER_USER_HELPER=y

Google Android setup.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     FAIL                FAIL
request_firmware_direct()              FAIL                FAIL
request_firmware_nowait(uevent=true)   FAIL                FAIL
request_firmware_nowait(uevent=false)  FAIL                FAIL
============================================================================

After this patch:
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n
CONFIG_FW_LOADER_USER_HELPER=y

Most common Linux distribution setup.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     FAIL                OK
request_firmware_direct()              FAIL                OK
request_firmware_nowait(uevent=true)   FAIL                OK
request_firmware_nowait(uevent=false)  FAIL                OK
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n
CONFIG_FW_LOADER_USER_HELPER=n

Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     FAIL                OK
request_firmware_direct()              FAIL                OK
request_firmware_nowait(uevent=true)   FAIL                OK
request_firmware_nowait(uevent=false)  FAIL                OK
============================================================================
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
CONFIG_FW_LOADER_USER_HELPER=y

Google Android setup.

API-type                               no-firmware-found   firmware-found
----------------------------------------------------------------------
request_firmware()                     OK                  OK
request_firmware_direct()              FAIL                OK
request_firmware_nowait(uevent=true)   OK                  OK
request_firmware_nowait(uevent=false)  OK                  OK
============================================================================

[0] https://bugzilla.kernel.org/show_bug.cgi?id=195477

CC: <stable@vger.kernel.org> [4.10+]
Cc: Ming Lei <ming.lei@redhat.com>
Fixes: 5b029624948d ("firmware: do not use fw_lock for fw_state protection")
Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>