In the path where intel_crt_detect_ddc() detects a CRT, if would return
true without freeing the edid.

Fixes: a2bd1f54 ("drm/i915: check whether we actually received an edid in detect_ddc")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v3.6+
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1484922525-6131-1-git-send-email-ander.conselvan.de.oliveira@intel.com
(cherry picked from commit c96b63a6)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

After we call drm_atomic_commit() on the load-detect state, we can free
our local reference. Upon restore, we only apply and free the previous state.

Fixes: 0853695c ("drm: Add reference counting to drm_atomic_state")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+
Link: http://patchwork.freedesktop.org/patch/msgid/20170119113749.2517-1-chris@chris-wilson.co.ukReviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
(cherry picked from commit 7abbd11f)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The .disable_display parameter was causing a fatal crash when fbdev
was dereferenced during driver init.

V1: protection in i915_drv.c
V2: Moved protection to intel_fbdev.c

Fixes: 43cee314 ("drm/i915/fbdev: Limit the global async-domain synchronization")
Testcase: igt/drv_module_reload/basic-no-display
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NClint Taylor <clinton.a.taylor@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1484775523-29428-1-git-send-email-clinton.a.taylor@intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: <stable@vger.kernel.org> # v4.8+
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
(cherry picked from commit 5b8cd075)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

intel_display_resume() may be called without an atomic state to restore,
i.e. dev_priv->modeset_reset_restore state is NULL. One such case is
following a lid open/close event and the forced modeset in
intel_lid_notify().
Reported-by: NStefan Seyfried <stefan.seyfried@googlemail.com>
Tested-by: NStefan Seyfried <stefan.seyfried@googlemail.com>
Fixes: 0853695c ("drm: Add reference counting to drm_atomic_state")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+
Link: http://patchwork.freedesktop.org/patch/msgid/20170115125825.18597-1-chris@chris-wilson.co.ukReviewed-by: NAnder Conselvan de Oliveira <conselvan2@gmail.com>
(cherry picked from commit 3c5e37f1)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

When the plane is invisible we may have all sorts of bogus stuff
in the coordinates, which we must ignore or else we might fail the
plane update. This started to happen on SKL when I moved the plane
offset computation to happen in the check phase. Previously we
happily ignored it all since we never called the update_plane hook
with an invisible plane.

Cc: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Fixes: b63a16f6 ("drm/i915: Compute display surface offset in the plane check hook for SKL+")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98258
Testcase: igt/pm_rpm/legacy-planes
Testcase: igt/pm_rpm/universal-planes
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1478550057-24864-3-git-send-email-ville.syrjala@linux.intel.com
(cherry picked from commit a5e4c7d0)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The WaDisableLSQCROPERFforOCL workaround has the side effect of
disabling an L3SQ optimization that has huge performance implications
and is unlikely to be necessary for the correct functioning of usual
graphic workloads.  Userspace is free to re-enable the workaround on
demand, and is generally in a better position to determine whether the
workaround is necessary than the DRM is (e.g. only during the
execution of compute kernels that rely on both L3 fences and HDC R/W
requests).

The same workaround seems to apply to BDW (at least to production
stepping G1) and SKL as well (the internal workaround database claims
that it does for all steppings, while the BSpec workaround table only
mentions pre-production steppings), but the DRM doesn't do anything
beyond whitelisting the L3SQCREG4 register so userspace can enable it
when it sees fit.  Do the same on KBL platforms.

Improves performance of the GFXBench4 gl_manhattan31 benchmark by 60%,
and gl_4 (AKA car chase) by 14% on a KBL GT2 running Mesa master --
This is followed by a regression of 35% and 10% respectively for the
same benchmarks and platform caused by my recent patch series
switching userspace to use the dataport constant cache instead of the
sampler to implement uniform pull constant loads, which caused us to
hit more heavily the L3 cache (and on platforms other than KBL had the
opposite effect of improving performance of the same two benchmarks).
The overall effect on KBL of this change combined with the recent
userspace change is respectively 4.6% and 2.6%.  SynMark2 OglShMapPcf
was affected by the constant cache changes (though it improved as it
did on other platforms rather than regressing), but is not
significantly affected by this patch (with statistical significance of
5% and sample size 20).

v2: Drop some more code to avoid unused variable warning.

Fixes: 738fa1b3 ("drm/i915/kbl: Add WaDisableLSQCROPERFforOCL")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99256Signed-off-by: NFrancisco Jerez <currojerez@riseup.net>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: beignet@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.7+
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
[Removed double Fixes tag]
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1484217894-20505-1-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit 8726f2fa)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

gvt-fixes-2017-01-16

vGPU reset fixes from Changbin.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

GT reset and FLR share some operations and they are both implemented in
our new function intel_gvt_reset_vgpu_locked(). This patch rewrite the
gt reset handler using this new function.

Besides, this new implementation fixed the old issue in GT reset. The
old implementation reset GGTT entries which is illegal. We only clear
GGTT entries at PCI level reset.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Our function tests found several issues related to reusing vGPU
instance. They are qemu reboot failure, guest tdr after reboot, host
hang when reboot guest. All these issues are caused by dirty status
inherited from last VM.

This patch fix all these issues by resetting a virtual GPU before VM
use it. The reset logical is put into a low level function
_intel_gvt_reset_vgpu(), which supports Device Model Level Reset, Full
GT Reset and Per-Engine Reset.

vGPU Device Model Level Reset (DMLR) simulates the PCI reset to reset
the whole vGPU to default state as when it is created, including GTT,
execlist, scratch pages, cfg space, mmio space, pvinfo page, scheduler
and fence registers. The ultimate goal of vGPU DMLR is that reuse a
vGPU instance by different virtual machines. When we reassign a vGPU
to a virtual machine we must issue such reset first.

Full GT Reset and Per-Engine GT Reset are soft reset flow for GPU engines
(Render, Blitter, Video, Video Enhancement). It is defined by GPU Spec.
Unlike the FLR, GT reset only reset particular resource of a vGPU per
the reset request. Guest driver can issue a GT reset by programming
the virtual GDRST register to reset specific virtual GPU engine or all
engines.

Since vGPU DMLR and GT reset can share some code so we implement both
these two into one single function intel_gvt_reset_vgpu_locked(). The
parameter dmlr is to identify if we will do FLR or GT reset. The
parameter engine_mask is to specific the engines that need to be
resetted. If value ALL_ENGINES is given for engine_mask, it means
the caller requests a full gt reset that we will reset all virtual
GPU engines.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Reviewed-by: NJike Song <jike.song@intel.com>
Reviewed-by: NKevin Tian <kevin.tian@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

This patch introduces a new function intel_vgpu_reset_mmio() to
reset vGPU MMIO space (virtual registers of the vGPU). The default
values are loaded as firmware during gvt inititiation.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Move the mmio space inititation function setup_vgpu_mmio()
and cleanup function clean_vgpu_mmio() in vgpu.c to dedicated
source file mmio.c, and rename them as intel_vgpu_init_mmio()
and intel_vgpu_clean_mmio() respectively.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

This patch introduces a new function intel_vgpu_reset_cfg_space()
to reset vGPU configuration space. This function will unmap gttmmio
and aperture if they are mapped before. Then entire cfg space will
be restored to default values.

Currently we only do such reset when vGPU is not owned by any VM
so we simply restore entire cfg space to default value, not following
the PCIe FLR spec that some fields should remain unchanged.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Move the configuration space inititation function setup_vgpu_cfg_space()
in vgpu.c to dedicated source file cfg_space.c, and rename the function
as intel_vgpu_init_cfg_space().
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

This patch introduces a new function intel_vgpu_reset_gtt() to reset
the all GTT related status, including GGTT, PPGTT, scratch page. This
function can free all shadowed PPGTT, clear all GGTT entry, and clear
scratch page to all zero. After this, we can ensure no gtt related
information can be leakaged from one VM to anothor one when assign
vgpu instance across different VMs (not simultaneously).
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

This patch introudces a new function intel_vgpu_reset_resource() to
reset allocated vgpu resources by intel_vgpu_alloc_resource(). So far
we only need clear the fence registers. The function _clear_vgpu_fence()
will reset both virtual and physical fence registers to 0.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Since commit fe115628 ("drm/i915: Implement pwrite without
struct-mutex") the lowlevel pwrite calls are now called without the
protection of struct_mutex, but pwrite_phys was still asserting that it
held the struct_mutex and later tried to drop and relock it.

Fixes: fe115628 ("drm/i915: Implement pwrite without struct-mutex")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: <drm-intel-fixes@lists.freedesktop.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170106152240.5793-1-chris@chris-wilson.co.ukReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
(cherry picked from commit 10466d2a)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Missed when rebasing patches, I failed to set ret to zero before
starting the unbind loop (which depends upon ret being zero).
Reported-by: NMatthew Auld <matthew.william.auld@gmail.com>
Fixes: 9332f3b1 ("drm/i915: Combine loops within i915_gem_evict_something")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170105155940.10033-1-chris@chris-wilson.co.ukReviewed-by: NMatthew Auld <matthew.william.auld@gmail.com>
Cc: <stable@vger.kernel.org> # v4.9+
(cherry picked from commit 121dfbb2)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

GVT-g fixes from Zhenya, "Please pull GVT-g device model fixes for
rc4. This is based on rc3 with new vfio/mdev interface change."
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

In gvt, almost all memory allocations are in sleepable contexts. It's
fault-prone to use GFP_ATOMIC everywhere. Replace it with GFP_KERNEL
wherever possible.
Signed-off-by: NJike Song <jike.song@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

The vgpu_create() routine we called returns meaningful errors to indicate
failures, so we'd better to pass it to our caller, the mdev framework,
whereby the sysfs is able to tell userspace what happened.
Signed-off-by: NJike Song <jike.song@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

According to the spec, ACPI OpRegion must be placed at a physical address
below 4G. That is, for a vGPU it must be associated with a GPA below 4G,
but on host side, it doesn't matter where the backing pages actually are.
So when allocating pages from host, the GFP_DMA32 flag is unnecessary.

Also the allocation is from a sleepable context, so GFP_ATOMIC is also
unnecessary.

This patch also removes INTEL_GVT_OPREGION_PORDER and use get_order()
instead.
Signed-off-by: NJike Song <jike.song@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Once idr_alloc gets called data is allocated within the idr list, if
any error occurs afterwards, we should undo that by idr_remove on the
error path.
Signed-off-by: NJike Song <jike.song@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

An idr should be initialized before use and destroyed afterwards.
Signed-off-by: NJike Song <jike.song@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

The vgpu->running_workload_num is used to determine whether a vgpu has
any workload running or not. So we should make sure the workload is
really done before we dec running_workload_num. Function
complete_current_workload is not the right place to do it, since this
function is still processing the workload. This patch move the dec op
afterward.

v2: move dec op before wake_up(&scheduler->workload_complete_wq) (Min He)
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Reviewed-by: NMin He <min.he@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

In the function workload_thread(), we invoke complete_current_workload()
to cleanup the just processed workload (workload will be freed there).
So we cannot access workload->req after that. This patch move
complete_current_workload() afterward.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Remove duplicated definition for resource size in aperture_gm.c
which are already defined in gvt.h. Need only one to take effect.
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Previous high mem size initialized for vGPU type was too small which caused
failure for some VMs. This trys to take minimal value of 384MB for each VM and
enlarge default high mem size to make guest driver happy.
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

In function intel_vgpu_emulate_mmio_read, the untracked mmio register is
dumped through kernel log, but the register value is not correct. This
patch fixes this issue.

V2: fix the fromat warning from checkpatch.pl.
Signed-off-by: NPei Zhang <pei.zhang@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

The readq and writeq are already offered by drm_os_linux.h. So we can
use them directly whithout dectecting their presence. This patch removed
the duplicated code.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

All mmio handlers should return a negetive value for failure, not 1.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Return ealier for a invalid access, else it would false set
tlb flag for RCS.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

The current prototype of new_mmio_info() uses void* for parameters read
and write, which are functions with precise calling conventions
(argument types and return type). Write down these conventions in
new_mmio_info() definition.

This has been reported by the following warnings when clang is used to
build the kernel:

    drivers/gpu/drm/i915/gvt/handlers.c:124:21: error: pointer type
    mismatch ('void *' and 'int (*)(struct intel_vgpu *, unsigned int,
    void *, unsigned int)') [-Werror,-Wpointer-type-mismatch]
            info->read = read ? read : intel_vgpu_default_mmio_read;
                              ^ ~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    drivers/gpu/drm/i915/gvt/handlers.c:125:23: error: pointer type
    mismatch ('void *' and 'int (*)(struct intel_vgpu *, unsigned int,
    void *, unsigned int)') [-Werror,-Wpointer-type-mismatch]
            info->write = write ? write : intel_vgpu_default_mmio_write;
                                ^ ~~~~~   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This allows the compiler to detect that sbi_ctl_mmio_write() returns a
"bool" value instead of an expected "int" one. Fix this.
Signed-off-by: NNicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

Pull USB fixes from Greg KH:
 "Here are a bunch of USB fixes for 4.10-rc3. Yeah, it's a lot, an
  artifact of the holiday break I think.

  Lots of gadget and the usual XHCI fixups for reported issues (one day
  that driver will calm down...) Also included are a bunch of usb-serial
  driver fixes, and for good measure, a number of much-reported MUSB
  driver issues have finally been resolved.

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

* tag 'usb-4.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (72 commits)
  USB: fix problems with duplicate endpoint addresses
  usb: ohci-at91: use descriptor-based gpio APIs correctly
  usb: storage: unusual_uas: Add JMicron JMS56x to unusual device
  usb: hub: Move hub_port_disable() to fix warning if PM is disabled
  usb: musb: blackfin: add bfin_fifo_offset in bfin_ops
  usb: musb: fix compilation warning on unused function
  usb: musb: Fix trying to free already-free IRQ 4
  usb: musb: dsps: implement clear_ep_rxintr() callback
  usb: musb: core: add clear_ep_rxintr() to musb_platform_ops
  USB: serial: ti_usb_3410_5052: fix NULL-deref at open
  USB: serial: spcp8x5: fix NULL-deref at open
  USB: serial: quatech2: fix sleep-while-atomic in close
  USB: serial: pl2303: fix NULL-deref at open
  USB: serial: oti6858: fix NULL-deref at open
  USB: serial: omninet: fix NULL-derefs at open and disconnect
  USB: serial: mos7840: fix misleading interrupt-URB comment
  USB: serial: mos7840: remove unused write URB
  USB: serial: mos7840: fix NULL-deref at open
  USB: serial: mos7720: remove obsolete port initialisation
  USB: serial: mos7720: fix parallel probe
  ...

Pull char/misc fixes from Greg KH:
 "Here are a few small char/misc driver fixes for 4.10-rc3.

  Two MEI driver fixes, and three NVMEM patches for reported issues, and
  a new Hyper-V driver MAINTAINER update. Nothing major at all, all have
  been in linux-next with no reported issues"

* tag 'char-misc-4.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  hyper-v: Add myself as additional MAINTAINER
  nvmem: fix nvmem_cell_read() return type doc
  nvmem: imx-ocotp: Fix wrong register size
  nvmem: qfprom: Allow single byte accesses for read/write
  mei: move write cb to completion on credentials failures
  mei: bus: fix mei_cldev_enable KDoc

Pull staging/IIO fixes from Greg KH:
 "Here are some staging and IIO driver fixes for 4.10-rc3.

  Most of these are minor IIO fixes of reported issues, along with one
  network driver fix to resolve an issue. And a MAINTAINERS update with
  a new mailing list. All of these, except the MAINTAINERS file update,
  have been in linux-next with no reported issues (the MAINTAINERS patch
  happened on Friday...)"

* tag 'staging-4.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  MAINTAINERS: add greybus subsystem mailing list
  staging: octeon: Call SET_NETDEV_DEV()
  iio: accel: st_accel: fix LIS3LV02 reading and scaling
  iio: common: st_sensors: fix channel data parsing
  iio: max44000: correct value in illuminance_integration_time_available
  iio: adc: TI_AM335X_ADC should depend on HAS_DMA
  iio: bmi160: Fix time needed to sleep after command execution
  iio: 104-quad-8: Fix active level mismatch for the preset enable option
  iio: 104-quad-8: Fix off-by-one errors when addressing IOR
  iio: 104-quad-8: Fix index control configuration

Several people report seeing warnings about inconsistent radix tree
nodes followed by crashes in the workingset code, which all looked like
use-after-free access from the shadow node shrinker.

Dave Jones managed to reproduce the issue with a debug patch applied,
which confirmed that the radix tree shrinking indeed frees shadow nodes
while they are still linked to the shadow LRU:

  WARNING: CPU: 2 PID: 53 at lib/radix-tree.c:643 delete_node+0x1e4/0x200
  CPU: 2 PID: 53 Comm: kswapd0 Not tainted 4.10.0-rc2-think+ #3
  Call Trace:
     delete_node+0x1e4/0x200
     __radix_tree_delete_node+0xd/0x10
     shadow_lru_isolate+0xe6/0x220
     __list_lru_walk_one.isra.4+0x9b/0x190
     list_lru_walk_one+0x23/0x30
     scan_shadow_nodes+0x2e/0x40
     shrink_slab.part.44+0x23d/0x5d0
     shrink_node+0x22c/0x330
     kswapd+0x392/0x8f0

This is the WARN_ON_ONCE(!list_empty(&node->private_list)) placed in the
inlined radix_tree_shrink().

The problem is with 14b46879 ("mm: workingset: move shadow entry
tracking to radix tree exceptional tracking"), which passes an update
callback into the radix tree to link and unlink shadow leaf nodes when
tree entries change, but forgot to pass the callback when reclaiming a
shadow node.

While the reclaimed shadow node itself is unlinked by the shrinker, its
deletion from the tree can cause the left-most leaf node in the tree to
be shrunk.  If that happens to be a shadow node as well, we don't unlink
it from the LRU as we should.

Consider this tree, where the s are shadow entries:

       root->rnode
            |
       [0       n]
        |       |
     [s    ] [sssss]

Now the shadow node shrinker reclaims the rightmost leaf node through
the shadow node LRU:

       root->rnode
            |
       [0        ]
        |
    [s     ]

Because the parent of the deleted node is the first level below the
root and has only one child in the left-most slot, the intermediate
level is shrunk and the node containing the single shadow is put in
its place:

       root->rnode
            |
       [s        ]

The shrinker again sees a single left-most slot in a first level node
and thus decides to store the shadow in root->rnode directly and free
the node - which is a leaf node on the shadow node LRU.

  root->rnode
       |
       s

Without the update callback, the freed node remains on the shadow LRU,
where it causes later shrinker runs to crash.

Pass the node updater callback into __radix_tree_delete_node() in case
the deletion causes the left-most branch in the tree to collapse too.

Also add warnings when linked nodes are freed right away, rather than
wait for the use-after-free when the list is scanned much later.

Fixes: 14b46879 ("mm: workingset: move shadow entry tracking to radix tree exceptional tracking")
Reported-by: NDave Chinner <david@fromorbit.com>
Reported-by: NHugh Dickins <hughd@google.com>
Reported-by: NAndrea Arcangeli <aarcange@redhat.com>
Reported-and-tested-by: NDave Jones <davej@codemonkey.org.uk>
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Leech <cleech@redhat.com>
Cc: Lee Duncan <lduncan@suse.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@linuxonhyperv.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

4.10-rc loadtest (even on x86, and even without THPCache) fails with
"fork: Cannot allocate memory" or some such; and /proc/meminfo shows
PageTables growing.

Commit 953c66c2 ("mm: THP page cache support for ppc64") that got
merged in rc1 removed the freeing of an unused preallocated pagetable
after do_fault_around() has called map_pages().

This is usually a good optimization, so that the followup doesn't have
to reallocate one; but it's not sufficient to shift the freeing into
alloc_set_pte(), since there are failure cases (most commonly
VM_FAULT_RETRY) which never reach finish_fault().

Check and free it at the outer level in do_fault(), then we don't need
to worry in alloc_set_pte(), and can restore that to how it was (I
cannot find any reason to pte_free() under lock as it was doing).

And fix a separate pagetable leak, or crash, introduced by the same
change, that could only show up on some ppc64: why does do_set_pmd()'s
failure case attempt to withdraw a pagetable when it never deposited
one, at the same time overwriting (so leaking) the vmf->prealloc_pte?
Residue of an earlier implementation, perhaps? Delete it.

Fixes: 953c66c2 ("mm: THP page cache support for ppc64")
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull kbuild fix from Michal Marek:
 "The asm-prototypes.h file added in the last merge window results in
  invalid code with CONFIG_KMEMCHECK=y. The net result is that genksyms
  segfaults.

  This pull request fixes the header, the genksyms fix is in my kbuild
  branch for 4.11"

* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  asm-prototypes: Clear any CPP defines before declaring the functions

The Greybus driver subsystem has a mailing list, so list it in the
MAINTAINERS file so that people know to send patches there as well.
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>