If data does not compress, it is better to leave it uncompressed
because we'll read it faster then. So do not compress data if we
save less than 64 bytes.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
[WATCHDOG] hpwdt: Fix kdump when using hpwdt
[WATCHDOG] hpwdt: set the mapped BIOS address space as executable
[WATCHDOG] iTCO_wdt: add PCI ID's for ICH9 & ICH10 chipsets
[WATCHDOG] iTCO_wdt : correct status clearing
[WATCHDOG] iTCO_wdt : problem with rebooting on new ICH9 based motherboards
[WATCHDOG] fix mtx1_wdt compilation failure
* 'linux-next' of git://git.infradead.org/ubifs-2.6:
UBIFS: pre-allocate bulk-read buffer
UBIFS: do not allocate too much
UBIFS: do not print scary memory allocation warnings
UBIFS: allow for gaps when dirtying the LPT
UBIFS: fix compilation warnings
MAINTAINERS: change UBI/UBIFS git tree URLs
UBIFS: endian handling fixes and annotations
UBIFS: remove printk
* 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: MMU: avoid creation of unreachable pages in the shadow
KVM: ppc: stop leaking host memory on VM exit
KVM: MMU: fix sync of ptes addressed at owner pagetable
KVM: ia64: Fix: Use correct calling convention for PAL_VPS_RESUME_HANDLER
KVM: ia64: Fix incorrect kbuild CFLAGS override
KVM: VMX: Fix interrupt loss during race with NMI
KVM: s390: Fix problem state handling in guest sigp handler
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
m68k: Update defconfigs for 2.6.28-rc7
macfb: Do not overflow fb_fix_screeninfo.id
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
[SCSI] stex: switch to block timeout
[SCSI] make scsi_eh_try_stu use block timeout
[SCSI] megaraid_sas: switch to block timeout
[SCSI] ibmvscsi: switch to block timeout
[SCSI] aacraid: switch to block timeout
[SCSI] zfcp: prevent double decrement on host_busy while being busy
[SCSI] zfcp: fix deadlock between wq triggered port scan and ERP
[SCSI] zfcp: eliminate race between validation and locking
[SCSI] zfcp: verify for correct rport state before scanning for SCSI devs
[SCSI] zfcp: returning an ERR_PTR where a NULL value is expected
[SCSI] zfcp: Fix opening of wka ports
[SCSI] zfcp: fix remote port status check
[SCSI] fc_transport: fix old bug on bitflag definitions
[SCSI] Fix hang in starved list processing
This fixes the MN10300 kernel module linking to match the toolchain. RELA
relocs don't use the value at the location being relocated. This has been
working because the tools always leave the value at the target location
cleared.
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If xpc.ko and gru.ko are both statically linked into the kernel, then
xpc_init() can get called before gru_init() and make a call to one of the
gru's exported functions before the gru has initialized itself. The end
result is a NULL dereference.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the CONFIG_SMP case the irq_choose_cpu() code was returning back
a logical cpu id not the physical id. We were writing that directly
into the HW register.
We need to be calling get_hard_smp_processor_id() so irq_choose_cpu()
always returns a physical cpu id.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Count the insertion of new pages in the statistics used to drive the
pageout scanning code. This should help the kernel quickly evict
streaming file IO.
We count on the fact that new file pages start on the inactive file LRU
and new anonymous pages start on the active anon list. This means
streaming file IO will increment the recent scanned file statistic, while
leaving the recent rotated file statistic alone, driving pageout scanning
to the file LRUs.
Pageout activity does its own list manipulation.
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: Gene Heskett <gene.heskett@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Devices which share the same queue, like floppies and mtd devices, get
registered multiple times in the bdi interface, but bdi accounts only the
last registered device of the devices sharing one queue.
On remove, all earlier registered devices leak, stay around in sysfs, and
cause "duplicate filename" errors if the devices are re-created.
This prevents the creation of multiple bdi interfaces per queue, and the
bdi device will carry the dev_t name of the block device which is the
first one registered, of the pool of devices using the same queue.
[akpm@linux-foundation.org: add a WARN_ON so we know which drivers are misbehaving]
Tested-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The previous patch from Alan Cox ("nfsd: fix vm overcommit crash",
commit 731572d39f) fixed the problem where
knfsd crashes on exported shmemfs objects and strict overcommit is set.
But the patch forgot supporting the case when CONFIG_SECURITY is
disabled.
This patch copies a part of his fix which is mainly for detecting a bug
earlier.
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Junjiro R. Okajima <hooanon05@yahoo.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We guarantee 400ns delay at the time of issuing the command.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Also while at it:
* Drop unused arguments from ide_complete_power_step().
* Move DEBUG_PM printk() from ide_end_drive_cmd() to
ide_complete_power_step().
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Respect current DMA setting during resume, otherwise PIO timings
may get destroyed if host uses shared PIO/MWDMA timings.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
It seems that on some nVidia controllers using AltStatus register
can be unreliable so default to Status register if the PCI device
is in Compatibility Mode. In order to achieve this:
* Add ide_pci_is_in_compatibility_mode() inline helper to <linux/ide.h>.
* Add IDE_HFLAG_BROKEN_ALTSTATUS host flag and set it in amd74xx host
driver for nVidia controllers in Compatibility Mode.
* Teach actual_try_to_identify() and drive_is_ready() about the new flag.
This fixes the regression caused by removal of CONFIG_IDEPCI_SHARE_IRQ
config option in 2.6.25 and using AltStatus register unconditionally when
available (kernel.org bugs #11659 and #10216).
[ Moreover for CONFIG_IDEPCI_SHARE_IRQ=y (which is what most people
and distributions use) it never worked correctly. ]
Thanks to Remy LABENE and Lars Winterfeld for help with debugging the problem.
More info at:
http://bugzilla.kernel.org/show_bug.cgi?id=11659http://bugzilla.kernel.org/show_bug.cgi?id=10216
Reported-by: Remy LABENE <remy.labene@free.fr>
Tested-by: Remy LABENE <remy.labene@free.fr>
Tested-by: Lars Winterfeld <lars.winterfeld@tu-ilmenau.de>
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Don't overflow the 16-character fb_fix_screeninfo id string (fixes some
console erasing and blanking artifacts). Have the ID default to "Unknown"
on machines with no built-in video and no nubus devices. Check for
fb_alloc_cmap failure.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (25 commits)
em28xx: remove backward compat macro added on a previous fix
V4L/DVB (9748): em28xx: fix compile warning
V4L/DVB (9743): em28xx: fix oops audio
V4L/DVB (9742): em28xx-alsa: implement another locking schema
V4L/DVB (9732): sms1xxx: use new firmware for Hauppauge WinTV MiniStick
V4L/DVB (9691): gspca: Move the video device to a separate area.
V4L/DVB (9690): gspca: Lock the subdrivers via module_get/put.
V4L/DVB (9689): gspca: Memory leak when disconnect while streaming.
V4L/DVB (9668): em28xx: fix a race condition with hald
V4L/DVB (9664): af9015: don't reconnect device in USB-bus
V4L/DVB (9647): em28xx: void having two concurrent control URB's
V4L/DVB (9646): em28xx: avoid allocating/dealocating memory on every control urb
V4L/DVB (9645): em28xx: Avoid memory leaks if registration fails
V4L/DVB (9639): Make dib0700 remote control support work with firmware v1.20
V4L/DVB (9635): v4l: s2255drv fix firmware test on big-endian
V4L/DVB (9634): Make sure the i2c gate is open before powering down tuner
V4L/DVB (9632): make em28xx aux audio input work
V4L/DVB (9631): Make s2api work for ATSC support
V4L/DVB (9627): em28xx: Avoid i2c register error for boards without eeprom
V4L/DVB (9608): Fix section mismatch warning for dm1105 during make
...
drivers/gpu/drm/i915/i915_irq.c: In function 'i915_disable_pipestat':
drivers/gpu/drm/i915/i915_irq.c:101: warning: control may reach end of non-void function 'i915_pipestat' being inlined
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix module removal bugs of i82875p_edac. Also i82975x_edac code seems to
have the same module removal bugs as in i82875p_edac.
The problems were:
1. In module removal i82875p_remove_one() is never called.
Variable i82875p_registered is newer changed from 1, which
guarantees i82875p_remove_one() is not called (and even if it were
called, it would be called in wrong order).
As a result, the edac_mc workque is not stopped and keeps probing.
If kernel debugging options are not enabled, user may not notice
anything going wrong.
if debugging options are enabled and I do "rmmod i82875p_edac", I
get:
edac debug: edac_pci_workq_function() checking
BUG: unable to handle kernel paging request at f882d16f
...
call trace:
[<f8834df3>] ? edac_mc_workq_function+0x55/0x7e [edac_core]
[<c0233974>] ? run_workqueue+0xd7/0x1a5
[<c023392f>] ? run_workqueue+0x92/0x1a5
[<f8834d9e>] ? edac_mc_workq_function+0x0/0x7e [edac_core]
[<c0233af9>] ? worker_thread+0xb7/0xc3
[<c0236a7b>] ? autoremove_wake_function+0x0/0x33
[<c0233a42>] ? worker_thread+0x0/0xc3
[<c0236809>] ? kthread+0x3b/0x61
[<c02367ce>] ? kthread+0x0/0x61
[<c0204587>] ? kernel_thread_helper+0x7/0x10
Fix for this is to get rid of needles variable i82875p_registered
altogether and run i82875p_remove_one() *before*
pci_unregister_driver().
2. edac_mc_del_mc() uses mci after freeing mci
edac_mc_del_mc() calls calls edac_remove_sysfs_mci_device(). The
kobject refcount of mci drops to 0 and mci is freed. After this
mci is accessed via debug print and i82875p_remove_one() still
uses mci->pvt and tries to free mci again with edac_mc_free().
The fix for this is add kobject_get(&mci->edac_mci_kobj) after
edac_mc_alloc(). Then the mci is still available after returning
from edac_mc_del_mc() with refcount 1, and mci->pvt is still
available. When i82875p_remove_one() finally calls edac_mc_free(),
this will cause kobject_put() and mci is released properly.
Signed-off-by: Jarkko Lavinen <jlavi@iki.fi>
Cc: Doug Thompson <norsk5@yahoo.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When I do "modprobe i82875p_edac" on my Asus P4C800 MB on kernels 2.6.26
or later, the module load fails due to BAR 0 collision. On 2.6.25 the
module loads just fine.
The overflow device on the MB seems to be hidden and its resources are not
allocated at normal PCI bus init. Log shows the missing resource problem:
EDAC DEBUG: i82875p_probe1()
PCI: 0000:00:06.0 reg 10 32bit mmio: [fecf0000, fecf0fff]
pci 0000:00:06.0: device not available because of BAR 0
[0xfecf0000-0xfecf0fff] collisions
EDAC i82875p: i82875p_setup_overfl_dev(): Failed to enable overflow
device
The patch below fixes this by calling pci_bus_assign_resources() after
the overflow device is revealed and added to the bus. With this patch
I am again able to load and use the module.
Signed-off-by: Jarkko Lavinen <jlavi@iki.fi>
Cc: Doug Thompson <norsk5@yahoo.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The commit aef7db4bd5 fixed the problem with
recursive locking in fb blanking code if blank is caused by user setting
the /sys/class/graphics/fb*/blank. However this broke the fbcon timeout
blanking.
If you use a driver that defines ->fb_blank operation and at the same time
that driver relies on other driver (e.g. backlight or lcd class) to blank
the screen, when the fbcon times out and tries to blank the fb, it will
call only fb driver blanker and won't notify the other driver. Thus FB
output is disabled, but the screen isn't blanked.
Restore fbcon blanking and at the same time apply the proper fix for the
above problem: if fbcon_blank is called with FBINFO_FLAG_USEREVENT, we are
already called through notification from fb_blank, thus we don't have to
blank the fb again.
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel-doc handles macros now (it has for quite some time), so change the
ntfs_debug() macro's kernel-doc to be just before the macro instead of
before a phony function prototype.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The method for listing varargs in kernel-doc notation is:
* @...: these arguments are printed by the @fmt argument
but scripts/kernel-doc is confused: it always lists varargs as:
... variable arguments
and ignores the @...: line's description, but then prints that
line after the list of function parameters as though it's
not part of the function parameters.
This patch makes kernel-doc print the supplied @... description if it is
present; otherwise a boilerplate "variable arguments" is printed.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2nd part of the fixes needed for
http://bugzilla.kernel.org/show_bug.cgi?id=11796.
When the idr tree is either grown or shrunk, then the update to the number
of layers and the top pointer were not atomic. This race caused crashes.
The attached patch fixes that by replicating the layers counter in each
layer, thus idr_find doesn't need idp->layers anymore.
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Clement Calmels <cboulte@gmail.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- pci_map_sg/dma_map_sg are used with a scatter gather list that doesn't
come from the block layer (e.g. some network drivers do).
- how IOMMUs merge adjacent elements of the scatter/gather list is
independent of how the block layer determines sees elements.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the error handling in sys_mmap2(). Currently, if the pgoff check
fails, fput() might have to be called (which it isn't), so do the pgoff
check first, before fget() is called.
Signed-off-by: David Howells <dhowells@redhat.com>
Reported-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The description for 'D' was missing in the comment... (causing me a
minute of WTF followed by looking at more of the code)
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The engine on some radeon variants locks up if color expansion is called
for non aligned source data. This patch enables a feature of the core
fbdev to request aligned input pixmaps and uses the HW clipping engine to
clip the output to the requested size
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=11875
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: James Cloos <cloos@jhcloos.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The spi master driver must have num_chipselect set to allow the bus to
initialise. Pass this through the platform data.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The spidev_to_sg() call in spi_s3c24xx_gpio.c was using the wrong method
to convert the spi device into the private data for the driver. Fix this
by using spi_master_get_devdata.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix unsafe order in dma mapping operation: always flush data from the
cache *BEFORE* invalidating it, to allow full duplex transfers where the
same buffer may be used for both writes and reads. Tested with mmc-spi.
Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It has been thought that the per-user file descriptors limit would also
limit the resources that a normal user can request via the epoll
interface. Vegard Nossum reported a very simple program (a modified
version attached) that can make a normal user to request a pretty large
amount of kernel memory, well within the its maximum number of fds. To
solve such problem, default limits are now imposed, and /proc based
configuration has been introduced. A new directory has been created,
named /proc/sys/fs/epoll/ and inside there, there are two configuration
points:
max_user_instances = Maximum number of devices - per user
max_user_watches = Maximum number of "watched" fds - per user
The current default for "max_user_watches" limits the memory used by epoll
to store "watches", to 1/32 of the amount of the low RAM. As example, a
256MB 32bit machine, will have "max_user_watches" set to roughly 90000.
That should be enough to not break existing heavy epoll users. The
default value for "max_user_instances" is set to 128, that should be
enough too.
This also changes the userspace, because a new error code can now come out
from EPOLL_CTL_ADD (-ENOSPC). The EMFILE from epoll_create() was already
listed, so that should be ok.
[akpm@linux-foundation.org: use get_current_user()]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: <stable@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Reported-by: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
According to the manual the "tdfOnExit" flag must be set on the last byte
we want to send. The PSC controller holds SS low until the flag is set.
However, the flag was set always on the last byte of the FIFO,
independently if it is the last byte of the transfer. This generates
spurious toggling of the SS signals that breaks the protocol of some
peripherals. Fix.
Signed-off-by: Stefano Babic <sbabic@denx.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use __initdata for data, not __init.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
make use of the new dmi device loading support to automatically load the
applesmc driver based on the dmi_match table.
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Cc: Nicolas Boichat <nicolas@boichat.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The netmos_9xx5_combo type assumes that PCI SSID provides always the
correct value for the number of parallel and serial ports, but there are
indeed broken devices with wrong numbers, which may result in Oops.
This patch simply adds the check of the array range.
Reference: Novell bnc#447067
https://bugzilla.novell.com/show_bug.cgi?id=447067
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes for memcg/memory hotplug.
While memory hotplug allocate/free memmap, page_cgroup doesn't free
page_cgroup at OFFLINE when page_cgroup is allocated via bootomem.
(Because freeing bootmem requires special care.)
Then, if page_cgroup is allocated by bootmem and memmap is freed/allocated
by memory hotplug, page_cgroup->page == page is no longer true.
But current MEM_ONLINE handler doesn't check it and update
page_cgroup->page if it's not necessary to allocate page_cgroup. (This
was not found because memmap is not freed if SPARSEMEM_VMEMMAP is y.)
And I noticed that MEM_ONLINE can be called against "part of section".
So, freeing page_cgroup at CANCEL_ONLINE will cause trouble. (freeing
used page_cgroup) Don't rollback at CANCEL.
One more, current memory hotplug notifier is stopped by slub because it
sets NOTIFY_STOP_MASK to return vaule. So, page_cgroup's callback never
be called. (low priority than slub now.)
I think this slub's behavior is not intentional(BUG). and fixes it.
Another way to be considered about page_cgroup allocation:
- free page_cgroup at OFFLINE even if it's from bootmem
and remove specieal handler. But it requires more changes.
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=12041
Signed-off-by: KAMEZAWA Hiruyoki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Tested-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jim Radford has reported that the vmap subsystem rewrite was sometimes
causing his VIVT ARM system to behave strangely (seemed like going into
infinite loops trying to fault in pages to userspace).
We determined that the problem was most likely due to a cache aliasing
issue. flush_cache_vunmap was only being called at the moment the page
tables were to be taken down, however with lazy unmapping, this can happen
after the page has subsequently been freed and allocated for something
else. The dangling alias may still have dirty data attached to it.
The fix for this problem is to do the cache flushing when the caller has
called vunmap -- it would be a bug for them to write anything else to the
mapping at that point.
That appeared to solve Jim's problems.
Reported-by: Jim Radford <radford@blackbean.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2:
ocfs2: fix regression in ocfs2_read_blocks_sync()
ocfs2: fix return value set in init_dlmfs_fs()
ocfs2: Small documentation update
ocfs2: fix wake_up in unlock_ast
ocfs2: initialize stack_user lvbptr
ocfs2: comments typo fix