01 May, 2012
4 commits
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The purpose of the upper bit of SRCU's per-CPU counters is to guarantee
that no reasonable series of srcu_read_lock() and srcu_read_unlock()
operations can return the value of the counter to its original value.
This guarantee is require only after the index has been switched to
the other set of counters, so at most one srcu_read_lock() can affect
a given CPU's counter. The number of srcu_read_unlock() operations
on a given counter is limited to the number of tasks in the system,
which given the Linux kernel's current structure is limited to far less
than 2^30 on 32-bit systems and far less than 2^62 on 64-bit systems.
(Something about a limited number of bytes in the kernel's address space.)Therefore, if srcu_read_lock() increments the upper bits, then
srcu_read_unlock() need not do so. In this case, an srcu_read_lock() and
an srcu_read_unlock() will flip the lower bit of the upper field of the
counter. An unreasonably large additional number of srcu_read_unlock()
operations would be required to return the counter to its initial value,
thus preserving the guarantee.This commit takes this approach, which further allows it to shrink
the size of the upper field to one bit, making the number of
srcu_read_unlock() operations required to return the counter to its
initial value even more unreasonable than before.Signed-off-by: Lai Jiangshan
Signed-off-by: Paul E. McKenney -
The fastpath in __synchronize_srcu() is designed to handle cases where
there are a large number of concurrent calls for the same srcu_struct
structure. However, the Linux kernel currently does not use SRCU in
this manner, so remove the fastpath checks for simplicity.Signed-off-by: Lai Jiangshan
Signed-off-by: Paul E. McKenney -
The current implementation of synchronize_srcu_expedited() can cause
severe OS jitter due to its use of synchronize_sched(), which in turn
invokes try_stop_cpus(), which causes each CPU to be sent an IPI.
This can result in severe performance degradation for real-time workloads
and especially for short-interation-length HPC workloads. Furthermore,
because only one instance of try_stop_cpus() can be making forward progress
at a given time, only one instance of synchronize_srcu_expedited() can
make forward progress at a time, even if they are all operating on
distinct srcu_struct structures.This commit, inspired by an earlier implementation by Peter Zijlstra
(https://lkml.org/lkml/2012/1/31/211) and by further offline discussions,
takes a strictly algorithmic bits-in-memory approach. This has the
disadvantage of requiring one explicit memory-barrier instruction in
each of srcu_read_lock() and srcu_read_unlock(), but on the other hand
completely dispenses with OS jitter and furthermore allows SRCU to be
used freely by CPUs that RCU believes to be idle or offline.The update-side implementation handles the single read-side memory
barrier by rechecking the per-CPU counters after summing them and
by running through the update-side state machine twice.This implementation has passed moderate rcutorture testing on both
x86 and Power. Also updated to use this_cpu_ptr() instead of per_cpu_ptr(),
as suggested by Peter Zijlstra.Reported-by: Peter Zijlstra
Signed-off-by: Paul E. McKenney
Signed-off-by: Paul E. McKenney
Acked-by: Peter Zijlstra
Reviewed-by: Lai Jiangshan -
Although rcutorture does invoke rcu_barrier() and friends, it cannot
really be called a torture test given that it invokes them only once
at the end of the test. This commit therefore introduces heavy-duty
rcutorture testing for rcu_barrier(), which may be carried out
concurrently with normal rcutorture testing.Signed-off-by: Paul E. McKenney
Signed-off-by: Paul E. McKenney
25 Apr, 2012
1 commit
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The rcutorture initialization code ignored the error returns from
rcu_torture_onoff_init() and rcu_torture_stall_init(). The rcutorture
cleanup code failed to NULL out a number of pointers. These bugs will
normally have no effect, but this commit fixes them nevertheless.Signed-off-by: Paul E. McKenney
22 Apr, 2012
6 commits
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Otherwise cpu_active_mask will not set, which lead to other issue.
Signed-off-by: Yong Zhang
Signed-off-by: Konrad Eisele
Reviewed-by: Srivatsa S. Bhat
Signed-off-by: David S. Miller -
Pull "ARM: SoC fixes" from Olof Johansson:
* at91, ux500, imx, omap and bcmring:
- at91 fixes for =m driver build issues, irqdomain fixes and config
dependency fixes
- ux500 kconfig dependency fixes and a smp wakeup bugfix
- imx idle bugfix and build fix due to irq domain changes
- omap uart pinmux fixes, softreset regression revert and misc fixes
- bcmring build error regression fix* ux500 and imx had some small defconfig updates in this branch
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (27 commits)
ARM: bcmring: fix UART declarations
ARM: imx: Fix imx5 idle logic bug
ARM: imx27-dt: Fix build due to removal of irq_domain_add_simple()
ARM: imx_v4_v5_defconfig: Add support for CONFIG_REGULATOR_FIXED_VOLTAGE
ARM: OMAP1: DMTIMER: fix broken timer clock source selection
ARM: OMAP: serial: Fix the ocp smart idlemode handling bug
ARM: OMAP2+: UART: Fix incorrect population of default uart pads
ARM: OMAP: sram: fix BUG in dpll code for !PM case
dmaengine: Kconfig: fix Atmel at_hdmac entry
USB: gadget/at91_udc: add gpio_to_irq() function to vbus interrupt
USB: ohci-at91: change annotations for probe/remove functions
leds-atmel-pwm.c: Make pwmled_probe() __devinit
ARM: at91: fix at91sam9261ek Ethernet dm9000 irq
ARM: at91: fix rm9200ek flash size
ARM: at91: remove empty at91_init_serial function
ARM: at91: fix typo in at91_pmc_base assembly declaration
ARM: at91: Export at91_matrix_base
ARM: at91: Export at91_pmc_base
ARM: at91: Export at91_ramc_base
ARM: at91: Export at91_st_base
... -
Pull MMC fixes from Chris Ball:
- Build fix for omap_hsmmc with OF against 3.4-rc1.
- Fix CONFIG_MMC_UNSAFE_RESUME semantics regression against 3.3, which
broke hotplug card detection when UNSAFE_RESUME is set.
- Fix a race condition in omap_hsmmc with runtime PM.
- Fix two libertas SDIO-powered-resume regressions.
- Small fixes for discard/sanitize, dw_mmc, cd-gpio and esdhc-imx.* tag 'mmc-fixes-for-3.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
mmc: core: Do not pre-claim host in suspend
mmc: dw_mmc: prevent NULL dereference for dma_ops
mmc: unbreak sdhci-esdhc-imx on i.MX25
mmc: cd-gpio: Include header to pickup exported symbol prototypes
mmc: sdhci: refine non-removable card checking for card detection
mmc: dw_mmc: Fix switch from DMA to PIO
mmc: remove MMC bus legacy suspend/resume method
mmc: omap_hsmmc: Get rid of of_have_populated_dt() usage
mmc: omap_hsmmc: build fix for CONFIG_OF=y and CONFIG_MMC_OMAP_HS=m
mmc: fixes for eMMC v4.5 sanitize operation
mmc: fixes for eMMC v4.5 discard operation -
Pull media fixes from Mauro Carvalho Chehab:
- Fixes a regression at DVB core when switching from DVB-S2 to DVB-S on
Kaffeine (Fedora 16 Bugzilla #812895);
- Fixes a mutex unlock at an error condition at drx-k;
- Fix winbond-cir set mode;
- mt9m032: Fix a compilation breakage with some random Kconfig;
- mt9m032: fix two dead locks;
- xc5000: don't require an special firmware (that won't be provided by
the vendor) just because the xtal frequency is different;
- V4L DocBook: fix some typos at multi-plane formats description.* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] xc5000: support 32MHz & 31.875MHz xtal using the 41.024.5 firmware
[media] V4L: mt9m032: fix compilation breakage
[media] V4L: DocBook: Fix typos in the multi-plane formats description
[media] V4L: mt9m032: fix two dead-locks
[media] rc-core: set mode for winbond-cir
[media] drxk: Does not unlock mutex if sanity check failed in scu_command()
[media] dvb_frontend: Fix a regression when switching back to DVB-S -
Pull MFD fixes from Samuel Ortiz:
"We have 3 build fixes, a OMAP USB host PHY reset fix and the twl6040
conversion to an i2c driver. The latter may not sound like a fix but
the twl6040 MFD driver won't probe without it, triggering an OMAP4
audio regression."* tag 'mfd-for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
mfd: Fix modular builds of rc5t583 regulator support
mfd: Fix asic3_gpio_to_irq
ARM: OMAP3: USB: Fix the EHCI ULPI PHY reset issue
mfd: Convert twl6040 to i2c driver, and separate it from twl core
mfd : Fix dbx500 compilation error
21 Apr, 2012
28 commits
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it's always current->mm
Signed-off-by: Al Viro
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pfm_vm_munmap() is simply vm_munmap() and pfm_remove_smpl_mapping()
always get current as the first argument.Signed-off-by: Al Viro
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... since exit_mmap() is coming and it will munmap() everything anyway.
In all other cases aio_free_ring() has ctx->mm == current->mm; moreover,
all other callers of vm_munmap() have mm == current->mm, so this will
allow us to get rid of mm argument of vm_munmap().Signed-off-by: Al Viro
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Since SDIO drivers may want to do some SDIO operations in their suspend
callback functions, we must not keep the host claimed when calling them.Daniel Drake reported that libertas_sdio encountered a deadlock in its
suspend function.Signed-off-by: Ulf Hansson
Tested-by: Daniel Drake
[stable@: please apply to 3.2-stable and 3.3-stable]
Cc: stable
Signed-off-by: Chris Ball -
Now, dma_ops is assumed that use the IDMAC. But if dma_ops is assigned
the pdata->dma_ops, we didn't ensure that callback function is defined.If the callback isn't defined, then we should run in PIO mode.
Signed-off-by: Jaehoon Chung
Signed-off-by: Kyungmin Park
Acked-by: Will Newton
Signed-off-by: Chris Ball -
This was broken by me in 37865fe91582582a6f6c00652f6a2b1ff71f8a78
("mmc: sdhci-esdhc-imx: fix timeout on i.MX's sdhci") where more
extensive tests would have shown that read or write of data to the
card were failing (even if the partition table was correctly read).Signed-off-by: Eric Bénard
Acked-by: Wolfram Sang
Cc: stable
Signed-off-by: Chris Ball -
Include the linux/mmc/cd-gpio.h header to pickup the prototypes
for the two exported symbols.This quiets the sparse warnings:
warning: symbol 'mmc_cd_gpio_request' was not declared. Should it be static?
warning: symbol 'mmc_cd_gpio_free' was not declared. Should it be static?Signed-off-by: H Hartley Sweeten
Acked-by: Guennadi Liakhovetski
Acked-by: Venkatraman S
Signed-off-by: Chris Ball -
Commit c79396c191bc19 ("mmc: sdhci: prevent card detection activity
for non-removable cards") disables card detection where the cards
are marked as non-removable.This makes sense, but the implementation detail of calling
mmc_card_is_removable() causes some problems, because
mmc_card_is_removable() is overloaded with CONFIG_MMC_UNSAFE_RESUME
semantics.In the OLPC XO case, we need CONFIG_MMC_UNSAFE_RESUME because our root
filesystem is stored on SD, but we also have external SD card slots
where we want automatic card detection.Refine the check to only apply to hosts marked as MMC_CAP_NONREMOVABLE,
which is defined to mean that the card is *really* nonremovable. This
could be revisited in future if we find a way to improve
CONFIG_MMC_UNSAFE_RESUME semantics.Signed-off-by: Daniel Drake
Acked-by: Chuanxiao Dong
[stable@: please apply to 3.3-stable]
Cc: stable
Signed-off-by: Chris Ball -
When dw_mci_pre_dma_transfer returns failure in some reasons,
dw_mci_submit_data will prepare to switch the PIO mode from DMA.
After switching to PIO mode, DMA(IDMAC in particular) is still
enabled. This makes the corruption in handling interrupt and
the driver lock-up.Signed-off-by: Seungwon Jeon
Acked-by: Will Newton
Signed-off-by: Chris Ball -
MMC bus is using legacy suspend/resume method, which is not compatible if
runtime pm callbacks are used. In this scenario, MMC bus suspend/resume
callbacks cannot be called when system entering S3. So change to use the
new defined dev_pm_ops for system sleeping mode.Tested on AM335x Platform. Solves major issue/crash reported at
http://www.mail-archive.com/linux-omap@vger.kernel.org/msg65425.htmlSigned-off-by: Chuanxiao Dong
Tested-by: Hebbar, Gururaja
Acked-by: Linus Walleij
Acked-by: Ulf Hansson
Signed-off-by: Chris Ball -
This continues the theme started with vm_brk() and vm_munmap():
vm_mmap() does the same thing as do_mmap(), but additionally does the
required VM locking.This uninlines (and rewrites it to be clearer) do_mmap(), which sadly
duplicates it in mm/mmap.c and mm/nommu.c. But that way we don't have
to export our internal do_mmap_pgoff() function.Some day we hopefully don't have to export do_mmap() either, if all
modular users can become the simpler vm_mmap() instead. We're actually
very close to that already, with the notable exception of the (broken)
use in i810, and a couple of stragglers in binfmt_elf.Signed-off-by: Linus Torvalds
-
Like the vm_brk() function, this is the same as "do_munmap()", except it
does the VM locking for the caller.Signed-off-by: Linus Torvalds
-
of_have_populated_dt() is not expected to be used in drivers but
instead only in early platform init code.
Drivers on the other hand should rely on dev->of_node or of_match_device().
Besides usage of of_have_populated_dt() also throws up build error as below
which was reported by Balaji TK, when omap_hsmmc is built as a module.ERROR: "allnodes" [drivers/mmc/host/omap_hsmmc.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2So get rid of all of_have_populated_dt() usage in omap_hsmmc driver and
instead use dev->of_node to make the same dicisions as earlier.Signed-off-by: Rajendra Nayak
Reported-by: Benoit Cousson
Cc: Sebastian Andrzej Siewior
Acked-by: Rob Herring
Reviewed-by: Balaji T K
Signed-off-by: Chris Ball -
Commit 46856a68dc ("mmc: omap_hsmmc: Convert hsmmc driver to use device tree")
introduced in 3.4-rc1 has a missing semi-colon, causing:drivers/mmc/host/omap_hsmmc.c:1745: error: expected ',' or ';' before 'extern'
Reported-by: Russell King
Signed-off-by: Chris Ball -
eMMC v4.5 sanitize operation erases all copies of unmapped
data. However trim or erase operations must be used first
to unmap the required sectors. That was not being done.Fixes apply to linux 3.2 on.
Signed-off-by: Adrian Hunter
Cc:
Acked-by: Jaehoon Chung
Acked-by: Linus Walleij
Signed-off-by: Chris Ball -
eMMC v4.5 discard operation is significantly different from the
existing trim operation because it is not guaranteed to work with
the new sanitize operation. Consequently mmc_can_trim() is
separated from mmc_can_discard().Also the new discard operation does not result in the sectors being
set to all-zeros, so discard_zeroes_data must not be set.In addition, the new discard has the same timeout as trim, but from
v4.5 trim is defined to use the hc timeout. The timeout calculation
is adjusted accordingly.Fixes apply to linux 3.2 on.
Signed-off-by: Adrian Hunter
Cc:
Acked-by: Jaehoon Chung
Acked-by: Linus Walleij
Signed-off-by: Chris Ball -
It does the same thing as "do_brk()", except it handles the VM locking
too.It turns out that all external callers want that anyway, so we can make
do_brk() static to just mm/mmap.c while at it.Signed-off-by: Linus Torvalds
-
…it/linusw/linux-pinctrl
Pull pinctrl fixes from Linus Walleij:
- Fixed compilation errors and warnings
- Stricter checks on the ops vtable* tag 'for-torvalds-20120418' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: implement pinctrl_check_ops
pinctrl: include <linux/bug.h> to prevent compile errors
pinctrl: fix compile error if not select PINMUX support -
Pull 3 tiny tty bugfixes from Greg Kroah-Hartman.
* tag 'tty-3.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
drivers/tty/amiserial.c: add missing tty_unlock
pch_uart: Fix dma channel unallocated issue
ARM: clps711x: serial driver hungs are a result of call disable_irq within ISR -
Pull USB fixes from Greg Kroah-Hartman:
"Here are a number of tiny USB fixes for 3.4-rc4.Most of them are in the USB gadget area, but a few other minor USB
driver and core fixes are here as well.Signed-off-by: Greg Kroah-Hartman "
* tag 'usb-3.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (36 commits)
USB: serial: cp210x: Fixed usb_control_msg timeout values
USB: ehci-tegra: don't call set_irq_flags(IRQF_VALID)
USB: yurex: Fix missing URB_NO_TRANSFER_DMA_MAP flag in urb
USB: yurex: Remove allocation of coherent buffer for setup-packet buffer
drivers/usb/misc/usbtest.c: add kfrees
USB: ehci-fsl: Fix kernel crash on mpc5121e
uwb: fix error handling
uwb: fix use of del_timer_sync() in interrupt
EHCI: always clear the STS_FLR status bit
EHCI: fix criterion for resuming the root hub
USB: sierra: avoid QMI/wwan interface on MC77xx
usb: usbtest: avoid integer overflow in alloc_sglist()
usb: usbtest: avoid integer overflow in test_ctrl_queue()
USB: fix deadlock in bConfigurationValue attribute method
usb: gadget: eliminate NULL pointer dereference (bugfix)
usb: gadget: uvc: Remove non-required locking from 'uvc_queue_next_buffer' routine
usb: gadget: rndis: fix Missing req->context assignment
usb: musb: omap: fix the error check for pm_runtime_get_sync
usb: gadget: udc-core: fix asymmetric calls in remove_driver
usb: musb: omap: fix crash when musb glue (omap) gets initialized
... -
Pull xen fixes from Konrad Rzeszutek Wilk:
- mechanism to work with misconfigured backends (where they are
advertised but in reality don't exist).
- two tiny compile warning fixes.
- proper error handling in gnttab_resume
- Not using VM_PFNMAP anymore to allow backends in the same domain.* tag 'stable/for-linus-3.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
Revert "xen/p2m: m2p_find_override: use list_for_each_entry_safe"
xen/resume: Fix compile warnings.
xen/xenbus: Add quirk to deal with misconfigured backends.
xen/blkback: Fix warning error.
xen/p2m: m2p_find_override: use list_for_each_entry_safe
xen/gntdev: do not set VM_PFNMAP
xen/grant-table: add error-handling code on failure of gnttab_resume -
This reverts commit cf450136bfde77c7f95065c91bffded4aa7fa731.
It breaks reboot on at least one Thinkpad T43, as reported by Jörg Otte:
"On reboot it shuts down as normal.
The last lines displayed are:>Unmounting temporary filesystems.. [OK]
>Deactivating swap... [OK]
>Unmounting local filesystems... [OK]
>Will now restart
> Restarting systemThen I hear it accessing the cd-drive, but then it's being stuck."
Jörg bisected the regression to this commit.
That commit fixes another machine (see
https://bugzilla.kernel.org/show_bug.cgi?id=11533
for details) that has a BIOS bug and doesn't support ACPI reset.
However, at least one of those other reporters no longer even has the
machine in question, and had a different workaround to begin with.
Besides, it clearly was a buggy BIOS. Let's not break the correct case
to fix that case.Reported-and-bisected-by: Jörg Otte
Cc: linux-acpi@vger.kernel.org
Cc: Len Brown
Cc: Peter Anvin
Signed-off-by: Linus Torvalds -
Commit 24aa07882b ("memblock, x86: Replace memblock_x86_reserve/
free_range() with generic ones") replaced x86 specific memblock
operations with the generic ones; unfortunately, it lost zero length
operation handling in the process making the kernel panic if somebody
tries to reserve zero length area.There isn't much to be gained by being cranky to zero length operations
and panicking is almost the worst response. Drop the BUG_ON() in
memblock_reserve() and update memblock_add_region/isolate_range() so
that all zero length operations are handled as noops.Signed-off-by: Tejun Heo
Cc: stable@vger.kernel.org
Reported-by: Valere Monseur
Bisected-by: Joseph Freeman
Tested-by: Joseph Freeman
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43098
Signed-off-by: Linus Torvalds -
Pyll hwmon fixes from Guenter Roeck:
"Two patches: Fix build warning in ads1015 driver, and fix bogus power
values with current BIOSes in fam15h_power driver."* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (ads1015) Fix build warning
hwmon: fam15h_power: fix bogus values with current BIOSes -
Pull crypto fixes from Herbert Xu:
- Locking fix for talitos driver
- Fix 64-bit counter overflow in SHA-512
- Build fix for ixp4xx.* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: talitos - properly lock access to global talitos registers
crypto: ixp4xx - include fix
crypto: sha512 - Fix byte counter overflow in SHA-512 -
Pull sound fixes from Takashi Iwai:
"Fixes for a few regressions of HD-audio, originated partly from 3.4
and partly 3.3.The fixes for ThinkPad docking-station are for 3.3 kernels, thus they
are based on 3.3 then merged back to 3.4, so that they can be merged
to stable tree cleanly. The non-trivial merge conflicts are because
of this action.In addition, a couple of trivial fixes for documentation and a long-
standing issue in the listing of built-in sound driver at boot time."* tag 'sound-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda/conexant - Set up the missing docking-station pins
ALSA: hda/conexant - Don't set HP pin-control bit unconditionally
ALSA: workaround: change the timing of alsa_sound_last_init()
ALSA: hda/sigmatel - Fix inverted mute LED
ALSA: hda/realtek - Fix regression on Quanta/Gericom KN1
ALSA: fix core/vmaster.c kernel-doc warning -
Pull HID fixes from Jiri Kosina:
"Fix for one particular device (bluetooth Tivo Slide) and change of
'default y' -> 'default n' for CONFIG_HID_BATTERY_STRENGTH which I
overlooked in the initial merge of the battery support"* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
HID: default HID_BATTERY_STRENGTH to no
HID: tivo: fix support for bluetooth version of tivo Slide -
Pull m68k arch fixes from Greg Ungerer:
"This contains four fixes for 3.4. Two fix and clean up compilation
for the nommu 68x328 CPU targets. The other two fix the platform
definition and multi-function pin setup of the second eth interface
on the ColdFire 5275 SoC."* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68knommu: make sure 2nd FEC eth interface pins are enabled on 5275 ColdFire
m68knommu: fix id number for second eth device on 5275 ColdFire
m68knommu: move and fix the 68VZ328 platform bootlogo.h
m68knommu: remove the unused bootlogo.h processing for 68EZ328 and 68VZ328
20 Apr, 2012
1 commit
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This reverts commit b960d6c43a63ebd2d8518b328da3816b833ee8cc.
If we have another thread (very likely) touched the list, we
end up hitting a problem "that the next element is wrong because
we should be able to cope with that. The problem is that the
next->next pointer would be set LIST_POISON1. " (Stefano's
comment on the patch).Reverting for now.
Suggested-by: Dan Carpenter
Acked-by: Stefano Stabellini
Signed-off-by: Konrad Rzeszutek Wilk
