When the user enables breakpoints through dr7, he can choose
between "local" or "global" enable bits but given how linux is
implemented, both have the same effect.

That said we don't keep track how the user enabled the breakpoints
so when the user requests the dr7 value, we only translate the
"enabled" status using the global enabled bits. It means that if
the user enabled a breakpoint using the local enabled bit, reading
back dr7 will set the global bit and clear the local one.

Apps like Wine expect a full dr7 POKEUSER/PEEKUSER match for emulated
softwares that implement old reverse engineering protection schemes.

We fix that by keeping track of the whole dr7 value given by the user
in the thread structure to drop this bug. We'll think about
something more proper later.

This fixes a 2.6.32 - 2.6.33-x ptrace regression.
Reported-and-tested-by: NMichael Stefaniuc <mstefani@redhat.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: NK.Prasad <prasad@linux.vnet.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Maneesh Soni <maneesh@linux.vnet.ibm.com>
Cc: Alexandre Julliard <julliard@winehq.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Maciej Rutecki <maciej.rutecki@gmail.com>

Before we had a generic breakpoint API, ptrace was accepting
breakpoints on NULL address in x86. The new API refuse them,
without given strong reasons. We need to follow the previous
behaviour as some userspace apps like Wine need such NULL
breakpoints to ensure old emulated software protections
are still working.

This fixes a 2.6.32 - 2.6.33-x ptrace regression.
Reported-and-tested-by: NMichael Stefaniuc <mstefani@redhat.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: NK.Prasad <prasad@linux.vnet.ibm.com>
Acked-by: NRoland McGrath <roland@redhat.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Maneesh Soni <maneesh@linux.vnet.ibm.com>
Cc: Alexandre Julliard <julliard@winehq.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Maciej Rutecki <maciej.rutecki@gmail.com>

Commit 22e19085 ("Honour event state for aux stream data")
introduced a bug where we would drop FORK events.

The thing is that we deliver FORK events to the child process'
event, which at that time will be PERF_EVENT_STATE_INACTIVE
because the child won't be scheduled in (we're in the middle of
fork).

Solve this twice, change the event state filter to exclude only
disabled (STATE_OFF) or worse, and deliver FORK events to the
current (parent).
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
LKML-Reference: <1266142324.5273.411.camel@laptop>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Print this:

Mapped keys:
        [d]     display refresh delay.                  (2)
        [e]     display entries (lines).                (46)
        [f]     profile display filter (count).         (5)
        [F]     annotate display filter (percent).      (5%)
        [s]     annotate symbol.                        (NULL)
        [S]     stop annotation.
        [K]     hide kernel_symbols symbols.            (no)
        [U]     hide user symbols.                      (no)
        [z]     toggle sample zeroing.                  (0)
        [qQ]    quit.

instead of:

Mapped keys:
        [d]     display refresh delay.                  (2)
        [e]     display entries (lines).                (46)
        [f]     profile display filter (count).         (5)
        [F]     annotate display filter (percent).      (5%)
        [s]     annotate symbol.                        (NULL)
        [S]     stop annotation.
        [K]     hide kernel_symbols symbols.                    (no)
        [U]     hide user symbols.                      (no)
        [z]     toggle sample zeroing.                  (0)
        [qQ]    quit.
Signed-off-by: NKirill Smelkov <kirr@landau.phys.spbu.ru>
Acked-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100212162059.GA30041@landau.phys.spbu.ru>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

cpumode bits are defined as such:

 #define PERF_RECORD_MISC_KERNEL                 (1 << 0)
 #define PERF_RECORD_MISC_USER                   (2 << 0)
 #define PERF_RECORD_MISC_HYPERVISOR             (3 << 0)

We need to compare against the complete value of cpumode,
otherwise hypervisor samples get incorrectly attributed as
userspace.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: fweisbec@gmail.com
LKML-Reference: <20100209034304.GA3702@kryten>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Change 'bp_len' type to __u64 to make it work across archs as
the s390 architecture watch point length can be upto 2^64.

reference:
	http://lkml.org/lkml/2010/1/25/212

This is an ABI change that is not backward compatible with
the previous hardware breakpoint info layout integrated in this
development cycle, a rebuilt of perf tools is necessary for
versions based on 2.6.33-rc1 - 2.6.33-rc6 to work with a
kernel based on this patch.
Signed-off-by: NMahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin <schwidefsky@de.ibm.com>
LKML-Reference: <20100130045518.GA20776@in.ibm.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  kernel/cred.c: use kmem_cache_free

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (23 commits)
  connector: Delete buggy notification code.
  be2net: use eq-id to calculate cev-isr reg offset
  Bluetooth: Use the control channel for raw HID reports
  Bluetooth: Add DFU driver for Atheros Bluetooth chipset AR3011
  Bluetooth: Redo checks in IRQ handler for shared IRQ support
  Bluetooth: Fix memory leak in L2CAP
  Bluetooth: Remove double free of SKB pointer in L2CAP
  cdc_ether: Partially revert "usbnet: Set link down initially ..."
  be2net: Fix memset() arg ordering.
  bonding: bond_open error return value
  ixgbe: if ixgbe_copy_dcb_cfg is going to fail learn about it early
  ixgbe: set the correct DCB bit for pg tx settings
  igbvf: fix issue w/ mapped_as_page being left set after unmap
  drivers/net: ks8851_mll ethernet network driver
  be2net: Bug fix to support newer generation of BE ASIC
  starfire: clean up properly if firmware loading fails
  mac80211: fix NULL pointer dereference when ftrace is enabled
  netfilter: ctnetlink: fix expectation mask dump
  ipv6: conntrack: Add member of user to nf_ct_frag6_queue structure
  ath9k: fix eeprom INI values override for 2GHz-only cards
  ...

This is the counterpart to cba76717
("pktcdvd: remove broken dev_t export of class devices").  Device is not
registered using dev_t, so it should not be destroyed using device_destroy
which looks up the device by dev_t.  This will fail and adding the device
again will fail with the "duplicate name" error.  This is fixed using
device_unregister instead of device_destroy.
Signed-off-by: NThadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Newly added memory can not be accessed via /dev/mem, because we do not
update the variables high_memory, max_pfn and max_low_pfn.

Add a function update_end_of_memory_vars() to update these variables for
64-bit kernels.

[akpm@linux-foundation.org: simplify comment]
Signed-off-by: NShaohui Zheng <shaohui.zheng@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Li Haicheng <haicheng.li@intel.com>
Reviewed-by: NWu Fengguang <fengguang.wu@intel.com>
Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

init_fault_attr_entries() should be init_fault_attr_dentries().

cleanup_fault_attr_entries() should be cleanup_fault_attr_dentries().
Signed-off-by: NAnton Blanchard <anton@samba.org>
Acked-by: NAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

hugetlb_sysfs_add_hstate is called by hugetlb_register_node directly
during init and also indirectly via sysfs after init.

This patch removes the __init tag from hugetlb_sysfs_add_hstate.
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move the ulite_console_setup to the .devinit section since it might be
called on probe, which is in devinit.  Fixes the crash below where the
uartlite hw is probed after the .init section is freed from the kernel.

uartlite: ttyUL0 at MMIO 0xc8000100 (irq = 30) is a uartlite
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<c176720e>] ulite_console_setup+0x6f/0xa8
*pdpt = 0000000036fb0001 *pde = 0000000000000000
Oops: 0000 [#1] PREEMPT SMP
last sysfs file: /sys/devices/pci0000:00/0000:00:1f.1/host0/uevent
Modules linked in: puffin(+) serio_raw

Pid: 151, comm: modprobe Not tainted (2.6.31.5-1.0.b1-b1 #1) POULSBO
EIP: 0060:[<c176720e>] EFLAGS: 00010246 CPU: 0
EIP is at ulite_console_setup+0x6f/0xa8
EAX: c16ec824 EBX: c16ec824 ECX: c176719f EDX: 00000000
ESI: 00000000 EDI: c17b42c4 EBP: f6fd1cf0 ESP: f6fd1cd8
 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
Process modprobe (pid: 151, ti=f6fd0000 task=f6fa1020 task.ti=f6fd0000)
Stack:
 c1031f51 00000000 00000000 00000246 c182237c f7742000 f6fd1d5c c11fd316
<0> c16ec85c f77420d4 0000001e 00000000 00000000 c1633e78 4f494d4d 63783020
<0> 30303038 00303031 f6fd1d3c c10e0786 f6fd1d48 00000000 f6fd1d48 00000000
Call Trace:
 [<c1031f51>] ? register_console+0xf6/0x1fc
 [<c11fd316>] ? uart_add_one_port+0x237/0x2bb
 [<c10e0786>] ? sysfs_add_one+0x13/0xd3
 [<c10e142f>] ? sysfs_do_create_link+0xba/0xfc
 [<c146f200>] ? ulite_probe+0x198/0x1eb
 [<c12064ee>] ? platform_drv_probe+0xc/0xe
 [<c120597b>] ? driver_probe_device+0x79/0x105
 [<c1205a8e>] ? __device_attach+0x28/0x30
 [<c120511f>] ? bus_for_each_drv+0x3d/0x67
 [<c1205af9>] ? device_attach+0x44/0x58
 [<c1205a66>] ? __device_attach+0x0/0x30
 [<c1204fb8>] ? bus_probe_device+0x1f/0x34
 [<c1203e68>] ? device_add+0x385/0x4c0
 [<c148491f>] ? _write_unlock+0x8/0x1f
 [<c1206aac>] ? platform_device_add+0xd9/0x11c
 [<c120c685>] ? mfd_add_devices+0x165/0x1bc
 [<f831b378>] ? puffin_probe+0x2d0/0x390 [puffin]
 [<c11a08ef>] ? pci_match_device+0xa0/0xa7
 [<c11a07bc>] ? local_pci_probe+0xe/0x10
 [<c11a11db>] ? pci_device_probe+0x43/0x66
 [<c120597b>] ? driver_probe_device+0x79/0x105
 [<c1205a4a>] ? __driver_attach+0x43/0x5f
 [<c120535d>] ? bus_for_each_dev+0x3d/0x67
 [<c1205852>] ? driver_attach+0x14/0x16
 [<c1205a07>] ? __driver_attach+0x0/0x5f
 [<c1204dea>] ? bus_add_driver+0xf9/0x220
 [<c1205c8f>] ? driver_register+0x8b/0xeb
 [<c11a1518>] ? __pci_register_driver+0x43/0x9f
 [<c10477ef>] ? __blocking_notifier_call_chain+0x40/0x4c
 [<f831f000>] ? puffin_init+0x0/0x48 [puffin]
 [<f831f017>] ? puffin_init+0x17/0x48 [puffin]
 [<c1001139>] ? do_one_initcall+0x4c/0x131
 [<c105607b>] ? sys_init_module+0xa7/0x1b7
 [<c1002a61>] ? syscall_call+0x7/0xb
 Code: 6e 74 00 00 00 92 33 00 00 18 00 0e 01 73 79 6e 63 65 2d 72 65 67 69 73 74 72 79 0c 00 49 32
00 00 14 00 09 01 61 6c 73 61 2d 69 <6e> 66 6f 00 00 00 42 37 00 00 10 00 07 01 6b 69 6c 6c 61 6c 6c
EIP: [<c176720e>] ulite_console_setup+0x6f/0xa8 SS:ESP 0068:f6fd1cd8
CR2: 0000000000000000
Signed-off-by: NRichard Röjfors <richard.rojfors@pelagicore.com>
Acked-by: NPeter Korsgaard <jacmet@sunsite.dk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The probe function passes a pointer to a struct fb_info to
platform_set_drvdata(), so don't interpret the return value of
platform_get_drvdata() as a pointer to struct imxfb_info.

The original imxfb_info *fbi backlight_power was NULL but in imxfb_suspend
it was 4 resulting in an oops as imxfb_suspend calls
imxfb_disable_controller(fbi) which in turn has

	if (fbi->backlight_power)
			fbi->backlight_power(0);
Signed-off-by: NUwe Kleine-König  <u.kleine-koenig@pengutronix.de>
Acked-by: NSascha Hauer <kernel@pengutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In cgroup_create(), if alloc_css_id() returns failure, the errno is not
propagated to userspace, so mkdir will fail silently.

To trigger this bug, we mount blkio (or memory subsystem), and create more
then 65534 cgroups.  (The number of cgroups is limited to 65535 if a
subsystem has use_id == 1)

 # mount -t cgroup -o blkio xxx /mnt
 # for ((i = 0; i < 65534; i++)); do mkdir /mnt/$i; done
 # mkdir /mnt/65534
 (should return ENOSPC)
 #
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Acked-by: NPaul Menage <menage@google.com>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When I use markup_oops.pl parse a x8664 oops, I got:

objdump: --start-address: bad number: NaN
No matching code found
This is because:
main::(./m.pl:228):	open(FILE, "objdump -dS --adjust-vma=$vmaoffset --start-address=$decodestart --stop-address=$decodestop $filename |") || die "Cannot start objdump";
  DB<3> p $decodestart
NaN

This NaN is from:
main::(./m.pl:176):	my $decodestart = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$func_offset");
  DB<2> p $func_offset
0x175

There is already a "0x" in $func_offset, another 0x makes it a NaN.

The $func_offset is from line:

	if ($line =~ /RIP: 0010:\[\<[0-9a-f]+\>\]  \[\<[0-9a-f]+\>\] ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]/) {
		$function = $1;
		$func_offset = $2;
	}

I make a patch to change "(0x[0-9a-f]+)\/0x[a-f0-9]/)" to "0x([0-9a-f]+)\/0x[a-f0-9]/)".
Signed-off-by: NHui Zhu <teawater@gmail.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When git has been set to always use color in .gitconfig then I get the
warning message

        Bad divisor in main::vcs_assign: 0

This is caused by vcs_file_signoffs not matching any commits due to the
pattern not understand the colour codes.  Fix this by telling git log to
never use colour.
Signed-off-by: NRichard Kennedy <richard@rsk.demon.co.uk>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

write_kmem() used to assume vwrite() always return the full buffer length.
However now vwrite() could return 0 to indicate memory hole.  This
creates a bug that "buf" is not advanced accordingly.

Fix it to simply ignore the return value, hence the memory hole.
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Otherwise vmalloc_to_page() will BUG().

This also makes the kmem read/write implementation aligned with mem(4):
"References to nonexistent locations cause errors to be returned." Here we
return -ENXIO (inspired by Hugh) if no bytes have been transfered to/from
user space, otherwise return partial read/write results.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The cache alias problem will happen if the changes of user shared mapping
is not flushed before copying, then user and kernel mapping may be mapped
into two different cache line, it is impossible to guarantee the coherence
after iov_iter_copy_from_user_atomic.  So the right steps should be:

	flush_dcache_page(page);
	kmap_atomic(page);
	write to page;
	kunmap_atomic(page);
	flush_dcache_page(page);

More precisely, we might create two new APIs flush_dcache_user_page and
flush_dcache_kern_page to replace the two flush_dcache_page accordingly.

Here is a snippet tested on omap2430 with VIPT cache, and I think it is
not ARM-specific:

	int val = 0x11111111;
	fd = open("abc", O_RDWR);
	addr = mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
	*(addr+0) = 0x44444444;
	tmp = *(addr+0);
	*(addr+1) = 0x77777777;
	write(fd, &val, sizeof(int));
	close(fd);

The results are not always 0x11111111 0x77777777 at the beginning as expected.  Sometimes we see 0x44444444 0x77777777.
Signed-off-by: NAnfei <anfei.zhou@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: <linux-arch@vger.kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix kfifo kernel-doc warnings:

Warning(kernel/kfifo.c:361): No description found for parameter 'total'
Warning(kernel/kfifo.c:402): bad line:  @ @lenout: pointer to output variable with copied data
Warning(kernel/kfifo.c:412): No description found for parameter 'lenout'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Stefani Seibold <stefani@seibold.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add missing braces for multiline 'if' statements in fm3130_probe.
Signed-off-by: NSergey Matyukevich <geomatsi@gmail.com>
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix the kernel oops when dev_dbg is called with mx3_fbi->txd == NULL

Fix the late initialisation of mx3fb->backlight_level.  If not, in the
chain of function started by init_fb_chan(), in __blank() call
sdc_set_brightness(mx3fb, mx3fb->backlight_level) that will shut down the
CONTRAST PWM output.
Signed-off-by: NAlberto Panizzo <maramaopercheseimorto@gmail.com>
Acked-by: Guennadi Liakhovetski <g.liakhovetski <at> gmx.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Eric Paris located a bug in idr.  With IDR_BITS of 6, it grows to three
layers when id 4096 is first allocated.  When that happens, idr wraps
incorrectly and searches the idr array ignoring the high bits.  The
following test code from Eric demonstrates the bug nicely.

#include <linux/idr.h>
#include <linux/kernel.h>
#include <linux/module.h>

static DEFINE_IDR(test_idr);

int init_module(void)
{
	int ret, forty95, forty96;
	void *addr;

	/* add 2 entries both with 4095 as the start address */
again1:
	if (!idr_pre_get(&test_idr, GFP_KERNEL))
		return -ENOMEM;
	ret = idr_get_new_above(&test_idr, (void *)4095, 4095, &forty95);
	if (ret) {
		if (ret == -EAGAIN)
			goto again1;
		return ret;
	}
	if (forty95 != 4095)
		printk(KERN_ERR "hmmm, forty95=%d\n", forty95);

again2:
	if (!idr_pre_get(&test_idr, GFP_KERNEL))
		return -ENOMEM;
	ret = idr_get_new_above(&test_idr, (void *)4096, 4095, &forty96);
	if (ret) {
		if (ret == -EAGAIN)
			goto again2;
		return ret;
	}
	if (forty96 != 4096)
		printk(KERN_ERR "hmmm, forty96=%d\n", forty96);

	/* try to find the 2 entries, noticing that 4096 broke */
	addr = idr_find(&test_idr, forty95);
	if ((int)addr != forty95)
		printk(KERN_ERR "hmmm, after find forty95=%d addr=%d\n", forty95, (int)addr);
	addr = idr_find(&test_idr, forty96);
	if ((int)addr != forty96)
		printk(KERN_ERR "hmmm, after find forty96=%d addr=%d\n", forty96, (int)addr);
	/* really weird, the entry which should be at 4096 is actually at 0!! */
	addr = idr_find(&test_idr, 0);
	if ((int)addr)
		printk(KERN_ERR "found an entry at id=0 for addr=%d\n", (int)addr);

	idr_remove(&test_idr, forty95);
	idr_remove(&test_idr, forty96);

	return 0;
}

void cleanup_module(void)
{
}

MODULE_AUTHOR("Eric Paris <eparis@redhat.com>");
MODULE_DESCRIPTION("Simple idr test");
MODULE_LICENSE("GPL");

This happens because when sub_alloc() back tracks it doesn't always do it
step-by-step while the over-the-limit detection assumes step-by-step
backtracking.  The logic in sub_alloc() looks like the following.

  restart:
    clear pa[top level + 1] for end cond detection
    l = top level
    while (true) {
	search for empty slot at this level
	if (not found) {
	    push id to the next possible value
	    l++
A:	    if (pa[l] is clear)
	        failed, return asking caller to grow the tree
	    if (going up 1 level gives more slots to search)
	        continue the while loop above with the incremented l
	    else
C:	        goto restart
	}
	adjust id accordingly to the found slot
	if (l == 0)
	    return found id;
	create lower level if not there yet
	record pa[l] and l--
    }

Test A is the fail exit condition but this assumes that failure is
propagated upwared one level at a time but the B optimization path breaks
the assumption and restarts the whole thing with a start value which is
above the possible limit with the current layers.  sub_alloc() assumes the
start id value is inside the limit when called and test A is the only exit
condition check, so it ends up searching for empty slot while ignoring
high set bit.

So, for 4095->4096 test, level0 search fails but pa[1] contains a valid
pointer.  However, going up 1 level wouldn't give any more empty slot so
it takes C and when the whole thing restarts nobody notices the high bit
set beyond the top level.

This patch fixes the bug by changing the fail exit condition check to full
id limit check.

Based-on-patch-from: Eric Paris <eparis@redhat.com>
Reported-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On Tue, Feb 02, 2010 at 02:57:14PM -0800, Greg KH (gregkh@suse.de) wrote:
> > There are at least two ways to fix it: using a big cannon and a small
> > one. The former way is to disable notification registration, since it is
> > not used by anyone at all. Second way is to check whether calling
> > process is root and its destination group is -1 (kind of priveledged
> > one) before command is dispatched to workqueue.
> 
> Well if no one is using it, removing it makes the most sense, right?
> 
> No objection from me, care to make up a patch either way for this?

Getting it is not used, let's drop support for notifications about
(un)registered events from connector.
Another option was to check credentials on receiving, but we can always
restore it without bugs if needed, but genetlink has a wider code base
and none complained, that userspace can not get notification when some
other clients were (un)registered.

Kudos for Sebastian Krahmer <krahmer@suse.de>, who found a bug in the
code.
Signed-off-by: NEvgeniy Polyakov <zbr@ioremap.net>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Free memory allocated using kmem_cache_zalloc using kmem_cache_free rather
than kfree.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,E,c;
@@

 x = \(kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache_alloc_node\)(c,...)
 ... when != x = E
     when != &x
?-kfree(x)
+kmem_cache_free(c,x)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Acked-by: NDavid Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Steve Dickson <steved@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJames Morris <jmorris@namei.org>

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cfq-iosched: Do not idle on async queues
  blk-cgroup: Fix potential deadlock in blk-cgroup
  block: fix bugs in bio-integrity mempool usage
  block: fix bio_add_page for non trivial merge_bvec_fn case
  drbd: null dereference bug
  drbd: fix max_segment_size initialization

Improve handling of fragmented per-CPU vmaps.  We previously don't free
up per-CPU maps until all its addresses have been used and freed.  So
fragmented blocks could fill up vmalloc space even if they actually had
no active vmap regions within them.

Add some logic to allow all CPUs to have these blocks purged in the case
of failure to allocate a new vm area, and also put some logic to trim
such blocks of a current CPU if we hit them in the allocation path (so
as to avoid a large build up of them).

Christoph reported some vmap allocation failures when using the per CPU
vmap APIs in XFS, which cannot be reproduced after this patch and the
previous bug fix.

Cc: linux-mm@kvack.org
Cc: stable@kernel.org
Tested-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NNick Piggin <npiggin@suse.de>
--
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

RCU list walking of the per-cpu vmap cache was broken.  It did not use
RCU primitives, and also the union of free_list and rcu_head is
obviously wrong (because free_list is indeed the list we are RCU
walking).

While we are there, remove a couple of unused fields from an earlier
iteration.

These APIs aren't actually used anywhere, because of problems with the
XFS conversion.  Christoph has now verified that the problems are solved
with these patches.  Also it is an exported interface, so I think it
will be good to be merged now (and Christoph wants to get the XFS
changes into their local tree).

Cc: stable@kernel.org
Cc: linux-mm@kvack.org
Tested-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NNick Piggin <npiggin@suse.de>
--
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  random: Remove unused inode variable
  crypto: padlock-sha - Add import/export support
  random: drop weird m_time/a_time manipulation

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
  GFS2: Use GFP_NOFS for alloc structure
  GFS2: Fix previous patch
  GFS2: Don't withdraw on partial rindex entries
  GFS2: Fix refcnt leak on gfs2_follow_link() error path

* 'sh/for-2.6.33' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
  sh: Fix access to released memory in clk_debugfs_register_one()
  sh: Fix access to released memory in dwarf_unwinder_cleanup()
  usb: r8a66597-hdc disable interrupts fix
  spi: spi_sh_msiof: Fixed data sampling on the correct edge

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  MIPS: 64-bit: Detect virtual memory size
  MIPS: AR7: Fix USB slave mem range typo
  MIPS: Alchemy: Fix dbdma ring destruction memory debugcheck.

Commit 221af7f8 ("Split 'flush_old_exec' into two functions") split
the function at the point of no return - ie right where there were no
more error cases to check.  That made sense from a technical standpoint,
but when we then also combined it with the actual personality setting
going in between flush_old_exec() and setup_new_exec(), it needs to be a
bit more careful.

In particular, we need to make sure that we really flush the old
personality bits in the 'flush' stage, rather than later in the 'setup'
stage, since otherwise we might be flushing the _new_ personality state
that we're just setting up.

So this moves the flags and personality flushing (and 'flush_thread()',
which is the arch-specific function that generally resets lazy FP state
etc) of the old process into flush_old_exec(), so that it doesn't affect
any state that execve() is setting up for the new process environment.

This was reported by Michal Simek as breaking his Microblaze qemu
environment.
Reported-and-tested-by: NMichal Simek <michal.simek@petalogix.com>
Cc: Peter Anvin <hpa@zytor.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Few weeks back, Shaohua Li had posted similar patch. I am reposting it
with more test results.

This patch does two things.

- Do not idle on async queues.

- It also changes the write queue depth CFQ drives (cfq_may_dispatch()).
  Currently, we seem to driving queue depth of 1 always for WRITES. This is
  true even if there is only one write queue in the system and all the logic
  of infinite queue depth in case of single busy queue as well as slowly
  increasing queue depth based on last delayed sync request does not seem to
  be kicking in at all.

This patch will allow deeper WRITE queue depths (subjected to the other
WRITE queue depth contstraints like cfq_quantum and last delayed sync
request).

Shaohua Li had reported getting more out of his SSD. For me, I have got
one Lun exported from an HP EVA and when pure buffered writes are on, I
can get more out of the system. Following are test results of pure
buffered writes (with end_fsync=1) with vanilla and patched kernel. These
results are average of 3 sets of run with increasing number of threads.

AVERAGE[bufwfs][vanilla]
-------
job       Set NR  ReadBW(KB/s)   MaxClat(us)    WriteBW(KB/s)  MaxClat(us)
---       --- --  ------------   -----------    -------------  -----------
bufwfs    3   1   0              0              95349          474141
bufwfs    3   2   0              0              100282         806926
bufwfs    3   4   0              0              109989         2.7301e+06
bufwfs    3   8   0              0              116642         3762231
bufwfs    3   16  0              0              118230         6902970

AVERAGE[bufwfs] [patched kernel]
-------
bufwfs    3   1   0              0              270722         404352
bufwfs    3   2   0              0              206770         1.06552e+06
bufwfs    3   4   0              0              195277         1.62283e+06
bufwfs    3   8   0              0              260960         2.62979e+06
bufwfs    3   16  0              0              299260         1.70731e+06

I also ran buffered writes along with some sequential reads and some
buffered reads going on in the system on a SATA disk because the potential
risk could be that we should not be driving queue depth higher in presence
of sync IO going to keep the max clat low.

With some random and sequential reads going on in the system on one SATA
disk I did not see any significant increase in max clat. So it looks like
other WRITE queue depth control logic is doing its job. Here are the
results.

AVERAGE[brr, bsr, bufw together] [vanilla]
-------
job       Set NR  ReadBW(KB/s)   MaxClat(us)    WriteBW(KB/s)  MaxClat(us)
---       --- --  ------------   -----------    -------------  -----------
brr       3   1   850            546345         0              0
bsr       3   1   14650          729543         0              0
bufw      3   1   0              0              23908          8274517

brr       3   2   981.333        579395         0              0
bsr       3   2   14149.7        1175689        0              0
bufw      3   2   0              0              21921          1.28108e+07

brr       3   4   898.333        1.75527e+06    0              0
bsr       3   4   12230.7        1.40072e+06    0              0
bufw      3   4   0              0              19722.3        2.4901e+07

brr       3   8   900            3160594        0              0
bsr       3   8   9282.33        1.91314e+06    0              0
bufw      3   8   0              0              18789.3        23890622

AVERAGE[brr, bsr, bufw mixed] [patched kernel]
-------
job       Set NR  ReadBW(KB/s)   MaxClat(us)    WriteBW(KB/s)  MaxClat(us)
---       --- --  ------------   -----------    -------------  -----------
brr       3   1   837            417973         0              0
bsr       3   1   14357.7        591275         0              0
bufw      3   1   0              0              24869.7        8910662

brr       3   2   1038.33        543434         0              0
bsr       3   2   13351.3        1205858        0              0
bufw      3   2   0              0              18626.3        13280370

brr       3   4   913            1.86861e+06    0              0
bsr       3   4   12652.3        1430974        0              0
bufw      3   4   0              0              15343.3        2.81305e+07

brr       3   8   890            2.92695e+06    0              0
bsr       3   8   9635.33        1.90244e+06    0              0
bufw      3   8   0              0              17200.3        24424392

So looks like it might make sense to include this patch.

Thanks
Vivek
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Linux kernel 2.6.32 and later allocate address space from the top of the
kernel virtual memory address space.

This patch implements virtual memory size detection for 64 bit MIPS CPUs
to avoid resulting crashes.
Signed-off-by: NGuenter Roeck <guenter.roeck@ericsson.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/935/Reviewed-by: NDavid Daney <ddaney@caviumnetworks.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

cev-isr reg offset for each function is better calculated using (any) eq-id
alloted to that function instead of using pci-func number(which
does not work in some configurations...)
Signed-off-by: NSathya Perla <sathyap@serverengines.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NMarek Skuczynski <mareksk7@gmail.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NMarek Skuczynski <mareksk7@gmail.com>
Acked-by: NMatt Fleming <matt@console-pimps.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>