The copyright/license notice says that the code is licensed under GPL v2
only (not GPL v2+), so let's use proper string in MODULE_LICENSE().
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

There is no need to explicitly set .owner for the driver, the core will do
it for us.
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Since reset and wake pin are optional the gpio structure for those
pins may be null. Therefore, they can't be blindly passed to
desc_to_gpio.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NFranklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Commit 5702222c ("Input: joydev - use memdup_user() to duplicate
memory from user-space") changed the kmalloc() and copy_from_user()
with a single call to memdup_user() but wrongly used the same error
path than the old code in which the buffer allocated by kmalloc() was
freed if copy_from_user() failed.

This is of course wrong since if memdup_user() fails, no memory was
allocated and the error in the error-valued pointer should be returned.

Fixes: 5702222c ("Input: joydev - use memdup_user() to duplicate
memory from user-space")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

This adds support for ROHM BU21023/24 Dual touch resistive touchscreens.
Signed-off-by: NYoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Modify parkbd driver to use the new Parallel Port device model.
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Merge with mainline to sync up with changes to parkbd driver.

The variable i is used to check the port to attach to and we are
supposed to save the reference of struct tgfx in the location given by
tgfx_base[i]. But after finding out the index, i is getting modified
again so we saved in a wrong index.

Fixes: 4de27a63 ("Input: turbografx - use parallel port device model")
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The variable i is used to check the port to attach to and we are
supposed to save the reference of struct gc in the location given by
gc_base[i]. But after finding out the index, i is getting modified again
so we saved in a wrong index.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Fixes: a517e87c ("Input: gamecon - use parallel port device model")
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The variable i is used to check the port to attach to and we are
supposed to save the reference of struct db9 in the location given by
db9_base[i]. But after finding out the index, i is getting modified again
so we saved in a wrong index.
While at it mark db9_base[i] as NULL after it is freed.

Fixes: 2260c419 ("Input: db9 - use parallel port device model")
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Pull strscpy string copy function implementation from Chris Metcalf.

Chris sent this during the merge window, but I waffled back and forth on
the pull request, which is why it's going in only now.

The new "strscpy()" function is definitely easier to use and more secure
than either strncpy() or strlcpy(), both of which are horrible nasty
interfaces that have serious and irredeemable problems.

strncpy() has a useless return value, and doesn't NUL-terminate an
overlong result.  To make matters worse, it pads a short result with
zeroes, which is a performance disaster if you have big buffers.

strlcpy(), by contrast, is a mis-designed "fix" for strlcpy(), lacking
the insane NUL padding, but having a differently broken return value
which returns the original length of the source string.  Which means
that it will read characters past the count from the source buffer, and
you have to trust the source to be properly terminated.  It also makes
error handling fragile, since the test for overflow is unnecessarily
subtle.

strscpy() avoids both these problems, guaranteeing the NUL termination
(but not excessive padding) if the destination size wasn't zero, and
making the overflow condition very obvious by returning -E2BIG.  It also
doesn't read past the size of the source, and can thus be used for
untrusted source data too.

So why did I waffle about this for so long?

Every time we introduce a new-and-improved interface, people start doing
these interminable series of trivial conversion patches.

And every time that happens, somebody does some silly mistake, and the
conversion patch to the improved interface actually makes things worse.
Because the patch is mindnumbing and trivial, nobody has the attention
span to look at it carefully, and it's usually done over large swatches
of source code which means that not every conversion gets tested.

So I'm pulling the strscpy() support because it *is* a better interface.
But I will refuse to pull mindless conversion patches.  Use this in
places where it makes sense, but don't do trivial patches to fix things
that aren't actually known to be broken.

* 'strscpy' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: use global strscpy() rather than private copy
  string: provide strscpy()
  Make asm/word-at-a-time.h available on all architectures

Pull md fixes from Neil Brown:
 "Assorted fixes for md in 4.3-rc.

  Two tagged for -stable, and one is really a cleanup to match and
  improve kmemcache interface.

* tag 'md/4.3-fixes' of git://neil.brown.name/md:
  md/bitmap: don't pass -1 to bitmap_storage_alloc.
  md/raid1: Avoid raid1 resync getting stuck
  md: drop null test before destroy functions
  md: clear CHANGE_PENDING in readonly array
  md/raid0: apply base queue limits *before* disk_stack_limits
  md/raid5: don't index beyond end of array in need_this_block().
  raid5: update analysis state for failed stripe
  md: wait for pending superblock updates before switching to read-only

Pull MIPS updates from Ralf Baechle:
 "This week's round of MIPS fixes:
   - Fix JZ4740 build
   - Fix fallback to GFP_DMA
   - FP seccomp in case of ENOSYS
   - Fix bootmem panic
   - A number of FP and CPS fixes
   - Wire up new syscalls
   - Make sure BPF assembler objects can properly be disassembled
   - Fix BPF assembler code for MIPS I"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: scall: Always run the seccomp syscall filters
  MIPS: Octeon: Fix kernel panic on startup from memory corruption
  MIPS: Fix R2300 FP context switch handling
  MIPS: Fix octeon FP context switch handling
  MIPS: BPF: Fix load delay slots.
  MIPS: BPF: Do all exports of symbols with FEXPORT().
  MIPS: Fix the build on jz4740 after removing the custom gpio.h
  MIPS: CPS: #ifdef on CONFIG_MIPS_MT_SMP rather than CONFIG_MIPS_MT
  MIPS: CPS: Don't include MT code in non-MT kernels.
  MIPS: CPS: Stop dangling delay slot from has_mt.
  MIPS: dma-default: Fix 32-bit fall back to GFP_DMA
  MIPS: Wire up userfaultfd and membarrier syscalls.

Pull irq fixes from Thomas Gleixner:
 "This update contains:

   - Fix for a long standing race affecting /proc/irq/NNN

   - One line fix for ARM GICV3-ITS counting the wrong data

   - Warning silencing in ARM GICV3-ITS.  Another GCC trying to be
     overly clever issue"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Count additional LPIs for the aliased devices
  irqchip/gic-v3-its: Silence warning when its_lpi_alloc_chunks gets inlined
  genirq: Fix race in register_irq_proc()

The MIPS syscall handler code used to return -ENOSYS on invalid
syscalls. Whilst this is expected, it caused problems for seccomp
filters because the said filters never had the change to run since
the code returned -ENOSYS before triggering them. This caused
problems on the chromium testsuite for filters looking for invalid
syscalls. This has now changed and the seccomp filters are always
run even if the syscall is invalid. We return -ENOSYS once we
return from the seccomp filters. Moreover, similar codepaths have
been merged in the process which simplifies somewhat the overall
syscall code.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11236/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Pull x86 fixes from Ingo Molnar:
 "Fixes all around the map: W+X kernel mapping fix, WCHAN fixes, two
  build failure fixes for corner case configs, x32 header fix and a
  speling fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/headers/uapi: Fix __BITS_PER_LONG value for x32 builds
  x86/mm: Set NX on gap between __ex_table and rodata
  x86/kexec: Fix kexec crash in syscall kexec_file_load()
  x86/process: Unify 32bit and 64bit implementations of get_wchan()
  x86/process: Add proper bound checks in 64bit get_wchan()
  x86, efi, kasan: Fix build failure on !KASAN && KMEMCHECK=y kernels
  x86/hyperv: Fix the build in the !CONFIG_KEXEC_CORE case
  x86/cpufeatures: Correct spelling of the HWP_NOTIFY flag

Pull timer fixes from Ingo Molnar:
 "An abs64() fix in the watchdog driver, and two clocksource driver
  NO_IRQ assumption fixes"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Fix abs() usage w/ 64bit values
  clocksource/drivers/keystone: Fix bad NO_IRQ usage
  clocksource/drivers/rockchip: Fix bad NO_IRQ usage

Pull EFI fixes from Ingo Molnar:
 "Two EFI fixes: one for x86, one for ARM, fixing a boot crash bug that
  can trigger under newer EFI firmware"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  arm64/efi: Fix boot crash by not padding between EFI_MEMORY_RUNTIME regions
  x86/efi: Fix boot crash by mapping EFI memmap entries bottom-up at runtime, instead of top-down

Pull drm fixes from Dave Airlie:
 "Bunch of fixes all over the place, all pretty small: amdgpu, i915,
  exynos, one qxl and one vmwgfx.

  There is also a bunch of mst fixes, I left some cleanups in the series
  as I didn't think it was worth splitting up the tested series"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (37 commits)
  drm/dp/mst: add some defines for logical/physical ports
  drm/dp/mst: drop cancel work sync in the mstb destroy path (v2)
  drm/dp/mst: split connector registration into two parts (v2)
  drm/dp/mst: update the link_address_sent before sending the link address (v3)
  drm/dp/mst: fixup handling hotplug on port removal.
  drm/dp/mst: don't pass port into the path builder function
  drm/radeon: drop radeon_fb_helper_set_par
  drm: handle cursor_set2 in restore_fbdev_mode
  drm/exynos: Staticize local function in exynos_drm_gem.c
  drm/exynos: fimd: actually disable dp clock
  drm/exynos: dp: remove suspend/resume functions
  drm/qxl: recreate the primary surface when the bo is not primary
  drm/amdgpu: only print meaningful VM faults
  drm/amdgpu/cgs: remove import_gpu_mem
  drm/i915: Call non-locking version of drm_kms_helper_poll_enable(), v2
  drm: Add a non-locking version of drm_kms_helper_poll_enable(), v2
  drm/vmwgfx: Fix a command submission hang regression
  drm/exynos: remove unused mode_fixup() code
  drm/exynos: remove decon_mode_fixup()
  drm/exynos: remove fimd_mode_fixup()
  ...

Pull input layer fixes from Dmitry Torokhov:
 "Fixes for two recent regressions (in Synaptics PS/2 and uinput
  drivers) and some more driver fixups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Revert "Input: synaptics - fix handling of disabling gesture mode"
  Input: psmouse - fix data race in __ps2_command
  Input: elan_i2c - add all valid ic type for i2c/smbus
  Input: zhenhua - ensure we have BITREVERSE
  Input: omap4-keypad - fix memory leak
  Input: serio - fix blocking of parport
  Input: uinput - fix crash when using ABS events
  Input: elan_i2c - expand maximum product_id form 0xFF to 0xFFFF
  Input: elan_i2c - add ic type 0x03
  Input: elan_i2c - don't require known iap version
  Input: imx6ul_tsc - fix controller name
  Input: imx6ul_tsc - use the preferred method for kzalloc()
  Input: imx6ul_tsc - check for negative return value
  Input: imx6ul_tsc - propagate the errors
  Input: walkera0701 - fix abs() calculations on 64 bit values
  Input: mms114 - remove unneded semicolons
  Input: pm8941-pwrkey - remove unneded semicolon
  Input: fix typo in MT documentation
  Input: cyapa - fix address of Gen3 devices in device tree documentation

This patch fixes one cases where abs() was being used with 64-bit
nanosecond values, where the result may be capped at 32-bits.

This potentially could cause watchdog false negatives on 32-bit
systems, so this patch addresses the issue by using abs64().
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1442279124-7309-2-git-send-email-john.stultz@linaro.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Pull arm64 fixes from Catalin Marinas:

 - Fix for transparent huge page change_protection() logic which was
   inadvertently changing a huge pmd page into a pmd table entry.

 - Function graph tracer panic fix caused by the return_to_handler code
   corrupting the multi-regs function return value (composite types).

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: ftrace: fix function_graph tracer panic
  arm64: Fix THP protection change logic

Pull m68k updates from Geert Uytterhoeven:
 "Summary:
   - Fix for accidental modification of arguments of syscall functions
   - Wire up new syscalls
   - Update defconfigs"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k/defconfig: Update defconfigs for v4.3-rc1
  m68k: Define asmlinkage_protect
  m68k: Wire up membarrier
  m68k: Wire up userfaultfd
  m68k: Wire up direct socket calls

When configuring the interrupt mapping for a new device, we
iterate over all the possible aliases to account for their
maximum MSI allocation. This was introduced by e8137f4f
("irqchip: gicv3-its: Iterate over PCI aliases to generate ITS configuration").

Turns out that the code doing that is a bit braindead, and repeatedly
accounts for the same device over and over.

Fix this by counting the actual alias that is passed to us by the
core code.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Alex Shi <alex.shi@linaro.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1443800646-8074-3-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

More agressive inlining in recent versions of GCC have uncovered
a new set of warnings:

 drivers/irqchip/irq-gic-v3-its.c: In function its_msi_prepare:
  drivers/irqchip/irq-gic-v3-its.c:1148:26: warning: lpi_base may be used
    uninitialized in this function [-Wmaybe-uninitialized]
     dev->event_map.lpi_base = lpi_base;
                          ^
 drivers/irqchip/irq-gic-v3-its.c:1116:6: note: lpi_base was declared here
  int lpi_base;
	      ^
 drivers/irqchip/irq-gic-v3-its.c:1149:25: warning: nr_lpis may be used
  uninitialized in this function [-Wmaybe-uninitialized]
   dev->event_map.nr_lpis = nr_lpis;
	                         ^
 drivers/irqchip/irq-gic-v3-its.c:1117:6: note: nr_lpis was declared here
  int nr_lpis;
	      ^
The warning is fairly benign (there is no code path that could
actually use uninitialized variables), but let's silence it anyway
by zeroing the variables on the error path.
Reported-by: NAlex Shi <alex.shi@linaro.org>
Tested-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1443800646-8074-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Pull dmaengine fixes from Vinod Koul:
 "This contains fixes spread throughout the drivers, and also fixes one
  more instance of privatecnt in dmaengine.

  Driver fixes summary:
   - bunch of pxa_dma fixes for reuse of descriptor issue, residue and
     no-requestor
   - odd fixes in xgene, idma, sun4i and zxdma
   - at_xdmac fixes for cleaning descriptor and block addr mode"

* tag 'dmaengine-fix-4.3-rc4' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: pxa_dma: fix residue corner case
  dmaengine: pxa_dma: fix the no-requestor case
  dmaengine: zxdma: Fix off-by-one for testing valid pchan request
  dmaengine: at_xdmac: clean used descriptor
  dmaengine: at_xdmac: change block increment addressing mode
  dmaengine: dw: properly read DWC_PARAMS register
  dmaengine: xgene-dma: Fix overwritting DMA tx ring
  dmaengine: fix balance of privatecnt
  dmaengine: sun4i: fix unsafe list iteration
  dmaengine: idma64: improve residue estimation
  dmaengine: xgene-dma: fix handling xgene_dma_get_ring_size result
  dmaengine: pxa_dma: fix initial list move

This adds support for the FT6x06 and the FT6x36 family of capacitive touch
panel controllers, in particular the FT6236.
Signed-off-by: NNoralf Trønnes <noralf@tronnes.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The PTR_ERR_OR_ZERO() helper function checks if a pointer contains an
errno code and returns it or return 0 if that's not the case. Use the
helper instead of open coding the same logic in the driver. This was
found with make coccicheck that complains with the following warning:

drivers/input/touchscreen/cyttsp4_i2c.c:53:1-3: WARNING: PTR_ERR_OR_ZERO can be used
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The PTR_ERR_OR_ZERO() helper function checks if a pointer contains an
errno code and returns it or return 0 if that's not the case. Use the
helper instead of open coding the same logic in the driver. This was
found with make coccicheck that complains with the following warning:

drivers/input/touchscreen/ads7846.c:532:1-3: WARNING: PTR_ERR_OR_ZERO can be used
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The invoked function already returns zero on success or a negative
errno code so there is no need to open code the logic in the caller.

This also fixes the following make coccicheck warning:

drivers/input/touchscreen/tps6507x-ts.c:57:5-8: WARNING: end returns can be simplified
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The invoked function already returns zero on success or a negative
errno code so there is no need to open code the logic in the caller.

This also fixes the following make coccicheck warnings:

end returns can be simplified and declaration on line 402 can be dropped
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The invoked function already returns zero on success or a negative
errno code so there is no need to open code the logic in the caller.

This also fixes the following make coccicheck warning:

end returns can be simplified and declaration on line 602 can be dropped
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: NHeiko Stuebner <heiko.stuebner@bq.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The retval variable isn't needed since isn't used in the function. Remove
the variable and just return 0 instead.

This also fixes the following make coccicheck warning:

drivers/input/misc/kxtj9.c:638:5-11: Unneeded variable: "retval". Return "0" on line 646
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The memdup_user() helper function can be used to duplicate a memory region
from user-space to kernel-space. There is no need to open code the same
logic using kmalloc() and copy_from_user() instead. This was found with
make coccicheck that reported the following warning:

drivers/input/joydev.c:447:10-17: WARNING opportunity for memdup_user
drivers/input/joydev.c:483:10-17: WARNING opportunity for memdup_user
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The driver depends on GOLDFISH but there isn't a build dependency
so it's a good idea to allow the driver to be built even if that
option is disabled, if the COMPILE_TEST option is enabled.

That way, the driver can be built with a config generated by make
allyesconfig and can be checked if a patch would break the build.
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

In the cases where the gpio chip fails to acquire the current state an
error is reported back to gpio_keys. This is currently interpreted as if
the line went high, which just confuses the developer.

This patch introduces an error print in this case and skipps the
reporting of a input event; to aid in debugging this issue.
Reported-by: NJohn Stultz <john.stultz@linaro.org>
Signed-off-by: NBjorn Andersson <bjorn.andersson@sonymobile.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Pull block fixes from Jens Axboe:
 "Another week, another round of fixes.

  These have been brewing for a bit and in various iterations, but I
  feel pretty comfortable about the quality of them.  They fix real
  issues.  The pull request is mostly blk-mq related, and the only one
  not fixing a real bug, is the tag iterator abstraction from Christoph.
  But it's pretty trivial, and we'll need it for another fix soon.

  Apart from the blk-mq fixes, there's an NVMe affinity fix from Keith,
  and a single fix for xen-blkback from Roger fixing failure to free
  requests on disconnect"

* 'for-linus' of git://git.kernel.dk/linux-block:
  blk-mq: factor out a helper to iterate all tags for a request_queue
  blk-mq: fix racy updates of rq->errors
  blk-mq: fix deadlock when reading cpu_list
  blk-mq: avoid inserting requests before establishing new mapping
  blk-mq: fix q->mq_usage_counter access race
  blk-mq: Fix use after of free q->mq_map
  blk-mq: fix sysfs registration/unregistration race
  blk-mq: avoid setting hctx->tags->cpumask before allocation
  NVMe: Set affinity after allocating request queues
  xen/blkback: free requests on disconnection

This reverts commit e51e3849: we
actually do want the device to work in extended W mode, as this is the
mode that allows us receiving multiple contact information.

Cc: stable@vger.kernel.org

During development it was found that a number of builds would panic
during the kernel init process, more specifically in 'delayed_fput()'.
The panic showed the kernel trying to access a memory address of
'0xb7fdc00' while traversing the 'delayed_fput_list' structure.
Comparing this memory address to the value of the pointer used on
builds that did not panic confirmed that the pointer on crashing
builds must have been corrupted at some stage earlier in the init
process.

By traversing the list earlier and earlier in the code it was found
that 'plat_mem_setup()' was responsible for corrupting the list.
Specifically the line:

    memory = cvmx_bootmem_phy_alloc(mem_alloc_size,
			__pa_symbol(&__init_end), -1,
			0x100000,
			CVMX_BOOTMEM_FLAG_NO_LOCKING);

Which would eventually call:

    cvmx_bootmem_phy_set_size(new_ent_addr,
		cvmx_bootmem_phy_get_size
		(ent_addr) -
		(desired_min_addr -
			ent_addr));

Where 'new_ent_addr'=0x4800000 (the address of 'delayed_fput_list')
and the second argument (size)=0xb7fdc00 (the address causing the
kernel panic). The job of this part of 'plat_mem_setup()' is to
allocate chunks of memory for the kernel to use. At the start of
each chunk of memory the size of the chunk is written, hence the
value 0xb7fdc00 is written onto memory at 0x4800000, therefore the
kernel panics when it goes back to access 'delayed_fput_list' later
on in the initialisation process.

On builds that were not crashing it was found that the compiler had
placed 'delayed_fput_list' at 0x4800008, meaning it wasn't corrupted
(but something else in memory was overwritten).

As can be seen in the first function call above the code begins to
allocate chunks of memory beginning from the symbol '__init_end'.
The MIPS linker script (vmlinux.lds.S) however defines the .bss
section to begin after '__init_end'. Therefore memory within the
.bss section is allocated to the kernel to use (System.map shows
'delayed_fput_list' and other kernel structures to be in .bss).

To stop the kernel panic (and the .bss section being corrupted)
memory should begin being allocated from the symbol '_end'.
Signed-off-by: NMatt Bennett <matt.bennett@alliedtelesis.co.nz>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: aleksey.makarov@auriga.com
Patchwork: https://patchwork.linux-mips.org/patch/11251/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>