Taking the cpu hotplug semaphore in a normal events workqueue
is unsafe because other tasks can wait for any workqueues with
it hold. This results in a deadlock.

Move the DBS timer into its own work queue which is not
affected by other work queue flushes to avoid this.

Has been acked by Venkatesh.

Cc: venkatesh.pallipadi@intel.com
Cc: cpufreq@lists.linux.org.uk
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Based on analysis&patch from Robert Hentosch

Observed on a Dell PE6850 with 16GB

The problem occurs very early on, when the kernel allocates space for the
temporary memory map called bootmap. The bootmap overlaps the EBDA region.
EBDA region is not historically reserved in the e820 mapping. When the
bootmap is freed it marks the EBDA region as usable.

If you notice in setup.c there is already code to work around the EBDA
in reserve_ebda_region(), this check however occurs after the bootmap
is allocated and doesn't prevent the bootmap from using this range.

AK: I redid the original patch. Thanks also to Jan Beulich for
spotting some mistakes.

Cc: Robert_Hentosch@dell.com
Cc: jbeulich@novell.com
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Playing with NMI watchdog on x86_64, I discovered that it didn't
do what I expected.  It always panic-ed, even when it didn't
happen from interrupt context.  This patch solves that
problem for me.  Also, in this case, do_exit() will be called
with interrupts disabled, I believe.  Would it be wise to also
call local_irq_enable() after nmi_exit()?
[Yes I added it -AK]

Currently, on x86_64, any NMI watchdog timeout will cause a panic
because the irq count will always be set to be in an interrupt
when do_exit() is called from die_nmi().  If we add nmi_exit() to
the die_nmi() call (since the nmi will never exit "normally")
it seems to solve this problem.  The following small program
can be used to trigger the NMI watchdog to reproduce this:
  main ()
  {
        iopl(3);
        for (;;) asm("cli");
  }
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I noticed this when poking around in this area.

The oops_begin() function in x86_64 would only conditionally claim
the die_lock if the call is nested, but oops_end() would always
release the spinlock. This patch adds a nest count for the die lock
so that the release of the lock is only done on the final oops_end().
Signed-off-by: NCorey Minyard <minyard@acm.org>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The IOMMU code can only deal with 8 northbridges. Error out when
more are found.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The patch addresses a problem with ACPI SCI interrupt entry, which gets
re-used, and the IRQ is assigned to another unrelated device.  The patch
corrects the code such that SCI IRQ is skipped and duplicate entry is
avoided.  Second issue came up with VIA chipset, the problem was caused by
original patch assigning IRQs starting 16 and up.  The VIA chipset uses
4-bit IRQ register for internal interrupt routing, and therefore cannot
handle IRQ numbers assigned to its devices.  The patch corrects this
problem by allowing PCI IRQs below 16.

Cc: len.brown@intel.com

Signed-off by: Natalie Protasevich <Natalie.Protasevich@unisys.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] remove asm-ia64/bitops.h self-inclusion
  [IA64] strcpy returns NULL pointer and not destination pointer

* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
  [IRDA] irda-usb: use NULL instead of 0
  [IPV4]: Remove likely in ip_rcv_finish()
  [NET]: Create netdev attribute_groups with class_device_add
  [CLASS DEVICE]: add attribute_group creation

* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild:
  kbuild: Do not overwrite makefile as anohter user
  kbuild: drivers/video/logo/ - fix ident glitch
  kbuild: fix gen_initramfs_list.sh
  kbuild modpost - relax driver data name
  kbuild: removing .tmp_versions considered harmful
  kbuild: fix modpost segfault for 64bit mipsel kernel

It is insane to be giving lease_init() the task of freeing the lock it is
supposed to initialise, given that the lock is not guaranteed to be
allocated on the stack. This causes lockups in fcntl_setlease().
Problem diagnosed by Daniel Hokka Zakrisson <daniel@hozac.com>

Also fix a slab leak in __setlease() due to an uninitialised return value.
Problem diagnosed by Björn Steinbrink.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: NDaniel Hokka Zakrisson <daniel@hozac.com>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Change the conditional of the outputmakefile rule to be evaluated entirely
in make, and add a conditional to not touch the generated makefile when e.g.
running 'make install' as root while the build was done as non-root. Also
adjust the comment describing this, and move the message printing and
redirection to mkmakefile.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

* master.kernel.org:/home/rmk/linux-2.6-arm:
  [ARM] 3507/1: Replace map_desc.physical with map_desc.pfn: aaed2000
  [ARM] 3506/1: aaec2000: debug-macro.S needs hardware.h
  [ARM] 3505/1: aaec2000: entry-macro.S needs asm/arch/irqs.h
  [ARM] 3504/1: Fix clcd includes for aaec2000
  [ARM] 3503/1: Fix map_desc structure for aaec2000
  [ARM] 3501/1: i.MX: fix lowlevel debug macros
  [ARM] rtc-sa1100: fix compiler warnings and error cleanup
  [ARM] Allow SA1100 RTC alarm to be configured for wakeup

Patch from Bellido Nicolas

aaed2000 map_desc.pfn conversion
Signed-off-by: NNicolas Bellido <ml@acolin.be>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Bellido Nicolas

Include hardware.h in debug-macro.S, otherwise io_p2v is undefined.
Signed-off-by: NNicolas Bellido <ml@acolin.be>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Bellido Nicolas

Since git commit 2b78838842346da390e8547cd37035184376d506, entry-macro.S needs to include asm/arch/irqs.h
Signed-off-by: NNicolas Bellido <ml@acolin.be>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Bellido Nicolas

Since this patch:
 [ARM] 3366/1: Allow the 16bpp mode configuration in the CLCD control register

linux/amba/bus.h needs to be included before linux/amba/clcd.h
Signed-off-by: NNicolas Bellido <ml@acolin.be>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Bellido Nicolas

Patch:
 [ARM] 2982/1: Replace map_desc.physical with map_desc.pfn: aaec2000
incorrectly expanded the struct map_desc for aaec2000.
Signed-off-by: NNicolas Bellido <ml@acolin.be>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Sascha Hauer

This patch fixes the addruart macro to work with both mmu enabled and
disabled.
Signed-off-by: NSascha Hauer <s.hauer@pengutonix.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This holds the task lock (and, for ptrace_attach, the tasklist_lock)
over the actual attach event, which closes a race between attacking to a
thread that is either doing a PTRACE_TRACEME or getting de-threaded.

Thanks to Oleg Nesterov for reminding me about this, and Chris Wright
for noticing a lost return value in my first version.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use NULL instead of 0 for a null pointer value (sparse warning):

drivers/net/irda/irda-usb.c:1781:30: warning: Using plain integer as NULL pointer

Also, correct timeout argument to use milliseconds instead of jiffies.
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is another result from my likely profiling tool
(dwalker@mvista.com just sent the patch of the profiling tool to
linux-kernel mailing list, which is similar to what I use).

On my system (not very busy, normal development machine within a
VMWare workstation), I see a 6/5 miss/hit ratio for this "likely".
Signed-off-by: NHua Zhong <hzhong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Atomically create attributes when class device is added. This avoids
the race between registering class_device (which generates hotplug
event), and the creation of attribute groups.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Extend the support of attribute groups in class_device's to allow
groups to be created as part of the registration process. This allows
network device's to avoid race between registration and creating
groups.

Note that unlike attributes that are a property of the class object,
the groups are a property of the class_device object. This is done
because there are different types of network devices (wireless for
example).
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix:
drivers/rtc/rtc-sa1100.c: In function `sa1100_rtc_proc':
drivers/rtc/rtc-sa1100.c:298: warning: unsigned int format, long unsigned int arg (arg 3)

and arrange for sa1100_rtc_open() to pass the devid to free_irq()
rather than NULL.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The SA1100 RTC alarm can be configured to wake up the CPU
from sleep mode, and the RTC driver has been using the
API to configure this mode.  Unfortunately, the code was
which sets the required bit in the hardware was missing.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Xiaoliang (David) Wei wrote:
> Hi gurus,
> 
>    I am reading the code of tcp_highspeed.c in the kernel and have a
> question on the hstcp_cong_avoid function, specifically the following
> AI part (line 136~143 in net/ipv4/tcp_highspeed.c ):
> 
>                /* Do additive increase */
>                if (tp->snd_cwnd < tp->snd_cwnd_clamp) {
>                        tp->snd_cwnd_cnt += ca->ai;
>                        if (tp->snd_cwnd_cnt >= tp->snd_cwnd) {
>                                tp->snd_cwnd++;
>                                tp->snd_cwnd_cnt -= tp->snd_cwnd;
>                        }
>                }
> 
>    In this part, when (tp->snd_cwnd_cnt == tp->snd_cwnd),
> snd_cwnd_cnt will be -1... snd_cwnd_cnt is defined as u16, will this
> small chance of getting -1 becomes a problem?
> Shall we change it by reversing the order of the cwnd++ and cwnd_cnt -= 
> cwnd?

Absolutely correct.  Thanks.
Signed-off-by: NJohn Heffner <jheffner@psc.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are out of date and don't tell the user anything useful.
The similar messages which IPV4 and the core networking used
to output were killed a long time ago.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Calling sock_orphan inside bh_lock_sock in dccp_close can lead to dead
locks.  For example, the inet_diag code holds sk_callback_lock without
disabling BH.  If an inbound packet arrives during that admittedly tiny
window, it will cause a dead lock on bh_lock_sock.  Another possible
path would be through sock_wfree if the network device driver frees the
tx skb in process context with BH enabled.

We can fix this by moving sock_orphan out of bh_lock_sock.

The tricky bit is to work out when we need to destroy the socket
ourselves and when it has already been destroyed by someone else.

By moving sock_orphan before the release_sock we can solve this
problem.  This is because as long as we own the socket lock its
state cannot change.

So we simply record the socket state before the release_sock
and then check the state again after we regain the socket lock.
If the socket state has transitioned to DCCP_CLOSED in the time being,
we know that the socket has been destroyed.  Otherwise the socket is
still ours to keep.

This problem was discoverd by Ingo Molnar using his lock validator.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It makes sense to add this simple statistic to keep track of received
multicast packets.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Discard an unexpected chunk in CLOSED state rather can calling BUG().
Signed-off-by: NSridhar Samudrala <sri@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use pskb_pull() to handle incoming COOKIE_ECHO and HEARTBEAT chunks that
are received as skb's with fragment list.
Signed-off-by: NSridhar Samudrala <sri@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is a rare situation that causes lksctp to go into infinite recursion
and crash the system.  The trigger is a packet that contains at least the
first two DATA fragments of a message bundled together. The recursion is
triggered when the user data buffer is smaller that the full data message.
The problem is that we clone the skb for every fragment in the message.
When reassembling the full message, we try to link skbs from the "first
fragment" clone using the frag_list. However, since the frag_list is shared
between two clones in this rare situation, we end up setting the frag_list
pointer of the second fragment to point to itself.  This causes
sctp_skb_pull() to potentially recurse indefinitely.

Proposed solution is to make a copy of the skb when attempting to link
things using frag_list.
Signed-off-by: NVladislav Yasevich <vladsilav.yasevich@hp.com>
Signed-off-by: NSridhar Samudrala <sri@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a deadlock situation in the receive path by allowing
temporary spillover of the receive buffer.

- If the chunk we receive has a tsn that immediately follows the ctsn,
  accept it even if we run out of receive buffer space and renege data with
  higher TSNs.
- Once we accept one chunk in a packet, accept all the remaining chunks
  even if we run out of receive buffer space.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NMark Butler <butlerm@middle.net>
Acked-by: NVlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: NSridhar Samudrala <sri@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

* master.kernel.org:/home/rmk/linux-2.6-mmc:
  [BLOCK] Fix oops on removal of SD/MMC card

Patch from Nicolas Pitre

... but only for user space.
Signed-off-by: NNicolas Pitre <nico@cam.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Nicolas Pitre

Intel PXA27x developers manual section 5.4.1.1 lists a priority
distribution for the DMA channels differently than what the code
currently assumes.  This patch fixes that.

Noticed by Simon Vogl <vogl@soft.uni-linz.ac.at>
Signed-off-by: NNicolas Pitre <nico@cam.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from George G. Davis

The ARM VFP FPSCR register is corrupted when a condition flags modifying
VFP instruction is followed by a non-condition flags modifying VFP
instruction and both instructions raise exceptions.  The fix is to
read the current FPSCR in between emulation of these two instructions
and use the current FPSCR value when handling the second exception.
Signed-off-by: NGeorge G. Davis <gdavis@mvista.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

asm-ia64/bitops.h includes itself.  The #ifndef _ASM_IA64_BITOPS_H
prevents this from being an issue, but it should still be removed.
Signed-off-by: NJon Mason <jdmason@us.ibm.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Bob Picco noted that 6edfba1b
dropped the -ffreestanding compiler flag from the top level
Makefile, which allows the compiler to substitute memcpy() in
places where strcpy() is used with a known size source string.
But the ia64 memcpy() returns 0 for success, and "bytes copied"
for failure.

Fix to return the address of the destination string (like
stdlibc version, and other architectures).  There are no
places where ia64 specific code makes use of the non-standard
return value.
Signed-off-by: NKen Chen <kenneth.w.chen@intel.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

The block layer keeps a reference (driverfs_dev) to the struct
device associated with the block device, and uses it internally
for generating uevents in block_uevent.

Block device uevents include umounting the partition, which can
occur after the backing device has been removed.

Unfortunately, this reference is not counted.  This means that
if the struct device is removed from the device tree, the block
layers reference will become stale.

Guard against this by holding a reference to the struct device
in add_disk(), and only drop the reference when we're releasing
the gendisk kobject - in other words when we can be sure that no
further uevents will be generated for this block device.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NJens Axboe <axboe@suse.de>