During module load, if we fail to initialise the rings, we abort the
load reporting EIO. However during resume, even though we report EIO as
we fail to reinitialize the ringbuffers, the resume continues and the
device is restored - albeit in a non-functional state. As we cannot
execute any commands on the GPU, it is effectively wedged, mark it so.

As we now preserve the ringbuffers across resume, this should prevent
UXA from falling into the trap of repeatedly sending invalid
batchbuffers and dropping all further rendering into /dev/null.
Reported-and-tested-by: NJiri Kosina <jkosina@suse.cz>
References: https://bugs.freedesktop.org/show_bug.cgi?id=76554Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NOscar Mateo <oscar.mateo@intel.com>
[danvet: Drop unused error, spotted by Oscar.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Even without enabling the ringbuffers to allow command execution, we can
still control the display engines to enable modesetting. So make the
ringbuffer initialization failure soft, and mark the GPU as wedged
instead.

v2: Only treat an EIO from ring initialisation as a soft failure, and
abort module load for any other failure, such as allocation failures.

v3: Add an *ERROR* prior to declaring the GPU wedged so that it stands
out like a sore thumb in the logs
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Tearing down the ring buffers across resume is overkill, risks
unnecessary failure and increases fragmentation.

After failure, since the device is still active we may end up trying to
write into the dangling iomapping and trigger an oops.

v2: stop_ringbuffers() was meant to call stop(ring) not
cleanup(ring) during resume!
Reported-by: NJae-hyeon Park <jhyeon@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=72351
References: https://bugs.freedesktop.org/show_bug.cgi?id=76554Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NOscar Mateo <oscar.mateo@intel.com>
[danvet: s/ring->obj == NULL/!intel_ring_initialized(ring)/ as
suggested by Oscar.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For readibility and guess at the meaning behind the constants.

v2: Claim only the meagerest connections with reality.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I don't think this is necessary; at least it doesn't appear to be on my
BYT.  Dropping it speeds up our shutdown code a little, in some cases
resulting in faster init times.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Next pull request, this time more of the drm de-midlayering work. The big
thing is that his patch series here removes everything from drm_bus except
the set_busid callback. Thierry has a few more patches on top of this to
make that one optional to.

With that we can ditch all the non-pci drm_bus implementations, which
Thierry has already done for the fake tegra host1x drm_bus.

Reviewed by Thierry, Laurent and David and now also survived some testing
on my intel boxes to make sure the irq fumble is fixed correctly ;-) The
last minute rebase was just to add the r-b tags from Thierry for the 2
patches I've redone.

* 'drm-init-cleanup' of git://people.freedesktop.org/~danvet/drm:
  drm/<drivers>: don't set driver->dev_priv_size to 0
  drm: Remove dev->kdriver
  drm: remove drm_bus->get_name
  drm: rip out dev->devname
  drm: inline drm_pci_set_unique
  drm: remove bus->get_irq implementations
  drm: pass the irq explicitly to drm_irq_install
  drm/irq: Look up the pci irq directly in the drm_control ioctl
  drm/irq: track the irq installed in drm_irq_install in dev->irq
  drm: rename dev->count_lock to dev->buf_lock
  drm: Rip out totally bogus vga_switcheroo->can_switch locking
  drm: kill drm_bus->bus_type
  drm: remove drm_dev_to_irq from drivers
  drm/irq: remove cargo-culted locking from irq_install/uninstall
  drm/irq: drm_control is a legacy ioctl, so pci devices only
  drm/pci: fold in irq_by_busid support
  drm/irq: simplify irq checks in drm_wait_vblank

bunch of coverity fixes all minor.

* 'drm-coverity-fixes' of git://people.freedesktop.org/~danvet/drm:
  drm: Fix error handling in drm_master_create
  drm/i2c/tda998x: Fix signed overflow issue
  drm/bochs: Remove unecessary NULL check in gem_free
  drm/bochs: Remove unnecessary NULL check in bo_unref
  drm/udl: Initialize ret in udl_driver_load
  drm/via: Remove unecessary NULL check
  drm/ast: Remove unecessary NULL check in gem_free
  drm/ast: Remove unnecessary NULL check in bo_unref
  drm/cirrus: Remove unecessary NULL check in gem_free
  drm/cirrus: Remove unnecessary NULL check in bo_unref
  drm/mgag200: Remove unecessary NULL check in gem_free
  drm/mgag200: Remove unecessary NULL check in bo_unref

Remove occurrences of unused struct qxl_device pointer in functions
qxl_ttm_fault() and qxl_init_mem_type().

Detected by Coverity: CID 1019128, CID 1019129.
Signed-off-by: NChristian Engelmayer <cengelma@gmx.at>
Signed-off-by: NDave Airlie <airlied@redhat.com>

For QXL hw we really want the bits to be replaced as we change
the preferred mode on the fly, and the same goes for virgl when
I get to it, however the original fix for this seems to have caused
a wierd regression on Intel G33 that in a stunning display of failure
at opposition to his normal self, Daniel failed to diagnose.

So we are left doing this, ugly ugly ugly ugly, Daniel you fixed
that G33 yet?, ugly, ugly.
Tested-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

drm-intel-next-2014-04-16:
- vlv infoframe fixes from Jesse
- dsi/mipi fixes from Shobhit
- gen8 pageflip fixes for LRI/SRM from Damien
- cmd parser fixes from Brad Volkin
- some prep patches for CHV, DRRS, ...
- and tons of little things all over
drm-intel-next-2014-04-04:
- cmd parser for gen7 but only in enforcing and not yet granting mode - the
  batch copying stuff is still missing. Also performance is a bit ... rough
  (Brad Volkin + OACONTROL fix from Ken).
- deprecate UMS harder (i.e. CONFIG_BROKEN)
- interrupt rework from Paulo Zanoni
- runtime PM support for bdw and snb, again from Paulo
- a pile of refactorings from various people all over the place to prep for new
  stuff (irq reworks, power domain polish, ...)

drm-intel-next-2014-04-04:
- cmd parser for gen7 but only in enforcing and not yet granting mode - the
  batch copying stuff is still missing. Also performance is a bit ... rough
  (Brad Volkin + OACONTROL fix from Ken).
- deprecate UMS harder (i.e. CONFIG_BROKEN)
- interrupt rework from Paulo Zanoni
- runtime PM support for bdw and snb, again from Paulo
- a pile of refactorings from various people all over the place to prep for new
  stuff (irq reworks, power domain polish, ...)

Conflicts:
	drivers/gpu/drm/i915/i915_gem_context.c

There was a very small race window where resume to kernel mode from a
Exception Path (or pure kernel mode which is true for most of ARC
exceptions anyways), was not disabling interrupts in restore_regs,
clobbering the exception regs

Anton found the culprit call flow (after many sleepless nights)

| 1. we got a Trap from user land
| 2. started to service it.
| 3. While doing some stuff on user-land memory (I think it is padzero()),
|     we got a DataTlbMiss
| 4. On return from it we are taking "resume_kernel_mode" path
| 5. NEED_RESHED is not set, so we go to "return from exception" path in
|     restore regs.
| 6. there seems to be IRQ happening
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: <stable@vger.kernel.org>   #3.10, 3.12, 3.13, 3.14
Cc: Anton Kolesov <Anton.Kolesov@synopsys.com>
Cc: Francois Bedard <Francois.Bedard@synopsys.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull sound fixes from Takashi Iwai:
 "A few collections of small eggs that have been gathered during the
  Easter holidays.  Mostly small ASoC fixes, with a HD-audio quirk and a
  workaround for Nvidia controller"

* tag 'sound-3.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Suppress CORBRP clear on Nvidia controller chips
  ALSA: hda - add headset mic detect quirk for a Dell laptop
  ASoC: jz4740: Remove Makefile entry for removed file
  ASoC: Intel: Fix audio crash due to negative address offset
  ASoC: dapm: Fix widget double free with auto-disable DAPM kcontrol
  ASoC: Intel: Fix incorrect sizeof() in sst_hsw_stream_get_volume()
  ASoC: Intel: some incorrect sizeof() usages
  ASoC: cs42l73: Convert to use devm_gpio_request_one
  ASoC: cs42l52: Convert to use devm_gpio_request_one
  ASoC: tlv320aic31xx: document that the regulators are mandatory
  ASoC: fsl_spdif: Fix wrong OFFSET of STC_SYSCLK_DIV
  ASoC: alc5623: Fix regmap endianness
  ASoC: tlv320aic3x: fix shared reset pin for DT
  ASoC: rsnd: fix clock prepare/unprepare

Pull drm fixes from Dave Airlie:
 "Smattering of fixes, i915, exynos, tegra, msm, vmwgfx.

  A bit of framebuffer reference counting fallout fixes, i915 GM45
  regression fix, DVI regression fix, vmware info leak between processes
  fix"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/exynos: use %pad for dma_addr_t
  drm/exynos: dsi: use IS_ERR() to check devm_ioremap_resource() results
  MAINTAINERS: update maintainer entry for Exynos DP driver
  drm/exynos: balance framebuffer refcount
  drm/i915: Move all ring resets before setting the HWS page
  drm/i915: Don't WARN nor handle unexpected hpd interrupts on gmch platforms
  drm/msm/mdp4: cure for the cursor blues (v2)
  drm/msm: default to XR24 rather than AR24
  drm/msm: fix memory leak
  drm/tegra: restrict plane loops to legacy planes
  drm/i915: Allow full PPGTT with param override
  drm/i915: Discard BIOS framebuffers too small to accommodate chosen mode
  drm/vmwgfx: Make sure user-space can't DMA across buffer object boundaries v2
  drm/i915: get power domain in case the BIOS enabled eDP VDD
  drm/i915: Don't check gmch state on inherited configs
  drm/i915: Allow user modes to exceed DVI 165MHz limit

Use %pad for dma_addr_t, because a dma_addr_t type can vary
based on build options. So, it prevents possible build warnings
in printks.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Reviewed-by: NDaniel Kurtz <djkurtz@chromium.org>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

devm_ioremap_resource() returns an error pointer, not NULL. Thus,
the result should be checked with IS_ERR().
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Recently, Exynos DP driver was moved from drivers/video/exynos/
directory to drivers/gpu/drm/exynos/ directory. So, I update
and add maintainer entry for Exynos DP driver.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

exynos_drm_crtc_mode_set assigns primary framebuffer to plane without
taking reference. Then during framebuffer removal it is dereferenced twice,
causing oops. The patch fixes it.
Signed-off-by: NAndrzej Hajda <a.hajda@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

single security fix, cc'd stable.

* 'vmwgfx-fixes-3.15' of git://people.freedesktop.org/~thomash/linux:
  drm/vmwgfx: Make sure user-space can't DMA across buffer object boundaries v2

The recent commit (ca460f86) changed the CORB RP reset procedure to
follow the specification with a couple of sanity checks.
Unfortunately, Nvidia controller chips seem not following this way,
and spew the warning messages like:
  snd_hda_intel 0000:00:10.1: CORB reset timeout#1, CORBRP = 0

This patch adds the workaround for such chips.  It just skips the new
reset procedure for the known broken chips.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Merge tag 'trace-fixes-v3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull ftrace bugfix from Steven Rostedt:
 "Takao Indoh reported that he was able to cause a ftrace bug while
  loading a module and enabling function tracing at the same time.

  He uncovered a race where the module when loaded will convert the
  calls to mcount into nops, and expects the module's text to be RW.
  But when function tracing is enabled, it will convert all kernel text
  (core and module) from RO to RW to convert the nops to calls to ftrace
  to record the function.  After the convertion, it will convert all the
  text back from RW to RO.

  The issue is, it will also convert the module's text that is loading.
  If it converts it to RO before ftrace does its conversion, it will
  cause ftrace to fail and require a reboot to fix it again.

  This patch moves the ftrace module update that converts calls to
  mcount into nops to be done when the module state is still
  MODULE_STATE_UNFORMED.  This will ignore the module when the text is
  being converted from RW back to RO"

* tag 'trace-fixes-v3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace/module: Hardcode ftrace_module_init() call into load_module()

Pull devicetree bug fixes from Grant Likely:
 "These are some important bug fixes that need to get into v3.15.

  This branch contains a pair of important bug fixes for the DT code:

   - Fix some incorrect binding property names before they enter common
     usage

   - Fix bug where some platform devices will be unable to get their
     interrupt number when they depend on an interrupt controller that
     is not available at device creation time.  This is a problem
     causing mainline to fail on a number of ARM platforms"

* tag 'dt-for-linus' of git://git.secretlab.ca/git/linux:
  of/irq: do irq resolution in platform_get_irq
  of: selftest: add deferred probe interrupt test
  dt: Fix binding typos in clock-names and interrupt-names

Pull powerpc fixes from Ben Herrenschmidt:
 "Here is a bunch of post-merge window fixes that have been accumulating
  in patchwork while I was on vacation or buried under other stuff last
  week.

  We have the now usual batch of LE fixes from Anton (sadly some new
  stuff that went into this merge window had endian issues, we'll try to
  make sure we do better next time)

  Some fixes and cleanups to the new 24x7 performance monitoring stuff
  (mostly typos and cleaning up printk's)

  A series of fixes for an issue with our runlatch bit, which wasn't set
  properly for offlined threads/cores and under KVM, causing potentially
  some counters to misbehave along with possible power management
  issues.

  A fix for kexec nasty race where the new kernel wouldn't "see" the
  secondary processors having reached back into firmware in time.

  And finally a few other misc (and pretty simple) bug fixes"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (33 commits)
  powerpc/4xx: Fix section mismatch in ppc4xx_pci.c
  ppc/kvm: Clear the runlatch bit of a vcpu before napping
  ppc/kvm: Set the runlatch bit of a CPU just before starting guest
  ppc/powernv: Set the runlatch bits correctly for offline cpus
  powerpc/pseries: Protect remove_memory() with device hotplug lock
  powerpc: Fix error return in rtas_flash module init
  powerpc: Bump BOOT_COMMAND_LINE_SIZE to 2048
  powerpc: Bump COMMAND_LINE_SIZE to 2048
  powerpc: Rename duplicate COMMAND_LINE_SIZE define
  powerpc/perf/hv-24x7: Catalog version number is be64, not be32
  powerpc/perf/hv-24x7: Remove [static 4096], sparse chokes on it
  powerpc/perf/hv-24x7: Use (unsigned long) not (u32) values when calling plpar_hcall_norets()
  powerpc/perf/hv-gpci: Make device attr static
  powerpc/perf/hv_gpci: Probe failures use pr_debug(), and padding reduced
  powerpc/perf/hv_24x7: Probe errors changed to pr_debug(), padding fixed
  powerpc/mm: Fix tlbie to add AVAL fields for 64K pages
  powerpc/powernv: Fix little endian issues in OPAL dump code
  powerpc/powernv: Create OPAL sglist helper functions and fix endian issues
  powerpc/powernv: Fix little endian issues in OPAL error log code
  powerpc/powernv: Fix little endian issues with opal_do_notifier calls
  ...

BUG_ON() is a big hammer, and should be used _only_ if there is some
major corruption that you cannot possibly recover from, making it
imperative that the current process (and possibly the whole machine) be
terminated with extreme prejudice.

The trivial sanity check in the vmacache code is *not* such a fatal
error.  Recovering from it is absolutely trivial, and using BUG_ON()
just makes it harder to debug for no actual advantage.

To make matters worse, the placement of the BUG_ON() (only if the range
check matched) actually makes it harder to hit the sanity check to begin
with, so _if_ there is a bug (and we just got a report from Srivatsa
Bhat that this can indeed trigger), it is harder to debug not just
because the machine is possibly dead, but because we don't have better
coverage.

BUG_ON() must *die*.  Maybe we should add a checkpatch warning for it,
because it is simply just about the worst thing you can ever do if you
hit some "this cannot happen" situation.
Reported-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A race exists between module loading and enabling of function tracer.

	CPU 1				CPU 2
	-----				-----
  load_module()
   module->state = MODULE_STATE_COMING

				register_ftrace_function()
				 mutex_lock(&ftrace_lock);
				 ftrace_startup()
				  update_ftrace_function();
				   ftrace_arch_code_modify_prepare()
				    set_all_module_text_rw();
				   <enables-ftrace>
				    ftrace_arch_code_modify_post_process()
				     set_all_module_text_ro();

				[ here all module text is set to RO,
				  including the module that is
				  loading!! ]

   blocking_notifier_call_chain(MODULE_STATE_COMING);
    ftrace_init_module()

     [ tries to modify code, but it's RO, and fails!
       ftrace_bug() is called]

When this race happens, ftrace_bug() will produces a nasty warning and
all of the function tracing features will be disabled until reboot.

The simple solution is to treate module load the same way the core
kernel is treated at boot. To hardcode the ftrace function modification
of converting calls to mcount into nops. This is done in init/main.c
there's no reason it could not be done in load_module(). This gives
a better control of the changes and doesn't tie the state of the
module to its notifiers as much. Ftrace is special, it needs to be
treated as such.

The reason this would work, is that the ftrace_module_init() would be
called while the module is in MODULE_STATE_UNFORMED, which is ignored
by the set_all_module_text_ro() call.

Link: http://lkml.kernel.org/r/1395637826-3312-1-git-send-email-indou.takao@jp.fujitsu.comReported-by: NTakao Indoh <indou.takao@jp.fujitsu.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: stable@vger.kernel.org # 2.6.38+
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

When we plug a 3-ring headset on the Dell machine (VID: 0x10ec0255,
SID: 0x10280674), the headset mic can't be detected, after apply this
patch, the headset mic can work well.

BugLink: https://bugs.launchpad.net/bugs/1297581
Cc: David Henningsson <david.henningsson@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: NHui Wang <hui.wang@canonical.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Merge tag 'asoc-v3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v3.15

A smattering of driver-specific fixes here, nothing generic.  The Cirrus
CODEC conversions to devm_ are leak fixes - the conversion adds missing
error handling code.

This patch fixes this section mismatch:

WARNING: vmlinux.o(.text+0x1efc4): Section mismatch in reference from
the function apm821xx_pciex_init_port_hw() to the function
.init.text:ppc4xx_pciex_wait_on_sdr.isra.9()

The function apm821xx_pciex_init_port_hw() references the function
__init ppc4xx_pciex_wait_on_sdr.isra.9().  This is often because
apm821xx_pciex_init_port_hw lacks a __init annotation or the
annotation of ppc4xx_pciex_wait_on_sdr.isra.9 is wrong.

apm821xx_pciex_init_port_hw is only referenced by a struct in
__initdata, so it should be safe to add __init to
apm821xx_pciex_init_port_hw.
Signed-off-by: NAlistair Popple <alistair@popple.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

When the guest cedes the vcpu or the vcpu has no guest to
run it naps. Clear the runlatch bit of the vcpu before
napping to indicate an idle cpu.
Signed-off-by: NPreeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Reviewed-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The secondary threads in the core are kept offline before launching guests
in kvm on powerpc: "371fefd6:KVM: PPC: Allow book3s_hv guests to use
SMT processor modes."

Hence their runlatch bits are cleared. When the secondary threads are called
in to start a guest, their runlatch bits need to be set to indicate that they
are busy. The primary thread has its runlatch bit set though, but there is no
harm in setting this bit once again. Hence set the runlatch bit for all
threads before they start guest.
Signed-off-by: NPreeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Reviewed-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Up until now we have been setting the runlatch bits for a busy CPU and
clearing it when a CPU enters idle state. The runlatch bit has thus
been consistent with the utilization of a CPU as long as the CPU is online.

However when a CPU is hotplugged out the runlatch bit is not cleared. It
needs to be cleared to indicate an unused CPU. Hence this patch has the
runlatch bit cleared for an offline CPU just before entering an idle state
and sets it immediately after it exits the idle state.
Signed-off-by: NPreeti U Murthy <preeti@linux.vnet.ibm.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Reviewed-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

While testing memory hot-remove, I found following dead lock:

Process #1141 is drmgr, trying to remove some memory, i.e. memory499.
It holds the memory_hotplug_mutex, and blocks when trying to remove file
"online" under dir memory499, in kernfs_drain(), at
        wait_event(root->deactivate_waitq,
                   atomic_read(&kn->active) == KN_DEACTIVATED_BIAS);

Process #1120 is trying to online memory499 by
   echo 1 > memory499/online

In .kernfs_fop_write, it uses kernfs_get_active() to increase
&kn->active, thus blocking process #1141. While itself is blocked later
when trying to acquire memory_hotplug_mutex, which is held by process

The backtrace of both processes are shown below:

[<c000000001b18600>] 0xc000000001b18600
[<c000000000015044>] .__switch_to+0x144/0x200
[<c000000000263ca4>] .online_pages+0x74/0x7b0
[<c00000000055b40c>] .memory_subsys_online+0x9c/0x150
[<c00000000053cbe8>] .device_online+0xb8/0x120
[<c00000000053cd04>] .online_store+0xb4/0xc0
[<c000000000538ce4>] .dev_attr_store+0x64/0xa0
[<c00000000030f4ec>] .sysfs_kf_write+0x7c/0xb0
[<c00000000030e574>] .kernfs_fop_write+0x154/0x1e0
[<c000000000268450>] .vfs_write+0xe0/0x260
[<c000000000269144>] .SyS_write+0x64/0x110
[<c000000000009ffc>] syscall_exit+0x0/0x7c

[<c000000001b18600>] 0xc000000001b18600
[<c000000000015044>] .__switch_to+0x144/0x200
[<c00000000030be14>] .__kernfs_remove+0x204/0x300
[<c00000000030d428>] .kernfs_remove_by_name_ns+0x68/0xf0
[<c00000000030fb38>] .sysfs_remove_file_ns+0x38/0x60
[<c000000000539354>] .device_remove_attrs+0x54/0xc0
[<c000000000539fd8>] .device_del+0x158/0x250
[<c00000000053a104>] .device_unregister+0x34/0xa0
[<c00000000055bc14>] .unregister_memory_section+0x164/0x170
[<c00000000024ee18>] .__remove_pages+0x108/0x4c0
[<c00000000004b590>] .arch_remove_memory+0x60/0xc0
[<c00000000026446c>] .remove_memory+0x8c/0xe0
[<c00000000007f9f4>] .pseries_remove_memblock+0xd4/0x160
[<c00000000007fcfc>] .pseries_memory_notifier+0x27c/0x290
[<c0000000008ae6cc>] .notifier_call_chain+0x8c/0x100
[<c0000000000d858c>] .__blocking_notifier_call_chain+0x6c/0xe0
[<c00000000071ddec>] .of_property_notify+0x7c/0xc0
[<c00000000071ed3c>] .of_update_property+0x3c/0x1b0
[<c0000000000756cc>] .ofdt_write+0x3dc/0x740
[<c0000000002f60fc>] .proc_reg_write+0xac/0x110
[<c000000000268450>] .vfs_write+0xe0/0x260
[<c000000000269144>] .SyS_write+0x64/0x110
[<c000000000009ffc>] syscall_exit+0x0/0x7c

This patch uses lock_device_hotplug() to protect remove_memory() called
in pseries_remove_memblock(), which is also stated before function
remove_memory():

 * NOTE: The caller must call lock_device_hotplug() to serialize hotplug
 * and online/offline operations before this call, as required by
 * try_offline_node().
 */
void __ref remove_memory(int nid, u64 start, u64 size)

With this lock held, the other process(#1120 above) trying to online the
memory block will retry the system call when calling
lock_device_hotplug_sysfs(), and finally find No such device error.
Signed-off-by: NLi Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

module_init should return 0 or a negative errno.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Bump the boot wrapper BOOT_COMMAND_LINE_SIZE to match the
kernel.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

I've had a report that the current limit is too small for
an automated network based installer. Bump it.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We have two definitions of COMMAND_LINE_SIZE, one for the kernel
and one for the boot wrapper. I assume this is so the boot
wrapper can be self sufficient and not rely on kernel headers.

Having two defines with the same name is confusing, I just
updated the wrong one when trying to bump it.

Make the boot wrapper define unique by calling it
BOOT_COMMAND_LINE_SIZE.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The catalog version number was changed from a be32 (with proceeding
32bits of padding) to a be64, update the code to treat it as a be64
Signed-off-by: NCody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NCody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NCody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: NCody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

fixup for "powerpc/perf: Add support for the hv gpci (get performance
counter info) interface".

Makes the "not enabled" message less awful (and hidden unless
debugging).
Signed-off-by: NCody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>