Now that we've got a generic perf-events based oprofile backend we might
as well make use of it seeing as SH doesn't do anything special with its
oprofile backend. Also introduce a new CONFIG_HW_PERF_EVENTS symbol so
that we can fallback to using the timer interrupt for oprofile if the
CPU doesn't support perf events.

Also, to avoid a section mismatch warning we need to annotate
oprofile_arch_exit() with an __exit marker.
Signed-off-by: NMatt Fleming <matt@console-pimps.org>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

Move the perf-events backend from arch/arm/oprofile into
drivers/oprofile so that the code can be shared between architectures.

This allows each architecture to maintain only a single copy of the PMU
accessor functions instead of one for both perf and OProfile. It also
becomes possible for other architectures to delete much of their
OProfile code in favour of the common code now available in
drivers/oprofile/oprofile_perf.c.
Signed-off-by: NMatt Fleming <matt@console-pimps.org>
Tested-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

In preparation for moving the majority of this oprofile code into an
architecture-neutral place separate the architecture-independent code
into oprofile_perf_init() and oprofile_perf_exit().
Signed-off-by: NMatt Fleming <matt@console-pimps.org>
Tested-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

In preparation for moving the generic functions out of this file, give
the functions more general names (e.g. remove "arm" from the names).
Signed-off-by: NMatt Fleming <matt@console-pimps.org>
Tested-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

Make op_name_from_perf_id() global so that we have a way for each
architecture to construct an oprofile name for op->cpu_type. We need to
remove the argument from the function prototype so that we can hide all
implementation details inside the function.
Signed-off-by: NMatt Fleming <matt@console-pimps.org>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

Introduce perf_pmu_name() helper function that returns the name of the
pmu. This gives us a generic way to get the name of a pmu regardless of
how an architecture identifies it internally.
Signed-off-by: NMatt Fleming <matt@console-pimps.org>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

The number of counters for the registered pmu is needed in a few places
so provide a helper function that returns this number.
Signed-off-by: NMatt Fleming <matt@console-pimps.org>
Tested-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

Merge branch 'urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile into perf/urgent

Some cpus still deliver spurious interrupts after disabling a
counter. This caused 'undelivered NMI' messages. This patch
fixes this. Introduced by:

  4177c42a: perf, x86: Try to handle unknown nmis with an enabled PMU
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: gorcunov@gmail.com <gorcunov@gmail.com>
Cc: fweisbec@gmail.com <fweisbec@gmail.com>
Cc: ying.huang@intel.com <ying.huang@intel.com>
Cc: ming.m.lin@intel.com <ming.m.lin@intel.com>
Cc: yinghai@kernel.org <yinghai@kernel.org>
Cc: andi@firstfloor.org <andi@firstfloor.org>
Cc: eranian@google.com <eranian@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20100915162034.GO13563@erda.amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The guest can use the paravirt clock in kvmclock.c which is used
by sched_clock(), which in turn is used by the tracing mechanism
for timestamps, which leads to infinite recursion.

Disable mcount/tracing for kvmclock.o.

Cc: stable@kernel.org
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

When using a paravirt clock, pvclock.c can be used by sched_clock(),
which in turn is used by the tracing mechanism for timestamps,
which leads to infinite recursion.

Disable mcount/tracing for pvclock.o.

Cc: stable@kernel.org
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
LKML-Reference: <4C9A9A3F.4040201@goop.org>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc: Prevent no-handler signal syscall restart recursion.
  sparc: Don't mask signal when we can't setup signal frame.
  sparc64: Fix race in signal instruction flushing.
  sparc64: Support RAW perf events.

Make sigreturn zero regs->trap, make do_signal() do the same on all
paths.  As it is, signal interrupting e.g. read() from fd 512 (==
ERESTARTSYS) with another signal getting unblocked when the first
handler finishes will lead to restart one insn earlier than it ought
to.  Same for multiple signals with in-kernel handlers interrupting
that sucker at the same time.  Same for multiple signals of any kind
interrupting that sucker on 64bit...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  bdi: Fix warnings in __mark_inode_dirty for /dev/zero and friends
  char: Mark /dev/zero and /dev/kmem as not capable of writeback
  bdi: Initialize noop_backing_dev_info properly
  cfq-iosched: fix a kernel OOPs when usb key is inserted
  block: fix blk_rq_map_kern bio direction flag
  cciss: freeing uninitialized data on error path

Inodes of devices such as /dev/zero can get dirty for example via
utime(2) syscall or due to atime update. Backing device of such inodes
(zero_bdi, etc.) is however unable to handle dirty inodes and thus
__mark_inode_dirty complains.  In fact, inode should be rather dirtied
against backing device of the filesystem holding it. This is generally a
good rule except for filesystems such as 'bdev' or 'mtd_inodefs'. Inodes
in these pseudofilesystems are referenced from ordinary filesystem
inodes and carry mapping with real data of the device. Thus for these
inodes we have to use inode->i_mapping->backing_dev_info as we did so
far. We distinguish these filesystems by checking whether sb->s_bdi
points to a non-trivial backing device or not.

Example: Assume we have an ext3 filesystem on /dev/sda1 mounted on /.
There's a device inode A described by a path "/dev/sdb" on this
filesystem. This inode will be dirtied against backing device "8:0"
after this patch. bdev filesystem contains block device inode B coupled
with our inode A. When someone modifies a page of /dev/sdb, it's B that
gets dirtied and the dirtying happens against the backing device "8:16".
Thus both inodes get filed to a correct bdi list.

Cc: stable@kernel.org
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

These devices don't do any writeback but their device inodes still can get
dirty so mark bdi appropriately so that bdi code does the right thing and files
inodes to lists of bdi carrying the device inodes.

Cc: stable@kernel.org
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Properly initialize this backing dev info so that writeback code does not
barf when getting to it e.g. via sb->s_bdi.

Cc: stable@kernel.org
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Explicitly clear the "in-syscall" bit when we have no signal
handler and back up the program counters to back up the system
call.
Reported-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't invoke the signal handler tracehook in that situation
either.
Reported-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

* 'for-linus/i2c/2636-rc5' of git://git.fluff.org/bjdooks/linux:
  i2c-omap: Make sure i2c bus is free before setting it to idle

The lock structs are currently protected by the BKL, but are accessed by
code in fs/locks.c and misc file system and DLM code.  These stubs will
allow all users to switch to the new interface before the implementation
is changed to a spinlock.
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NSage Weil <sage@newdream.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If the i2c bus receives an interrupt with both BB (bus busy) and
ARDY (register access ready) statuses set during the tranfer of the last message
the bus was put to idle while still busy.

This caused bus to timeout.
Signed-off-by: NMathias Nyman <mathias.nyman@nokia.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix nohz balance kick
  sched: Fix user time incorrectly accounted as system time on 32-bit

Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hw breakpoints: Fix pid namespace bug
  x86: Fix instruction breakpoint encoding
  oprofile: Add Support for Intel CPU Family 6 / Model 22 (Intel Celeron 540)
  kprobes: Fix Kconfig dependency

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: select CRYPTO
  ceph: check mapping to determine if FILE_CACHE cap is used
  ceph: only send one flushsnap per cap_snap per mds session
  ceph: fix cap_snap and realm split
  ceph: stop sending FLUSHSNAPs when we hit a dirty capsnap
  ceph: correctly set 'follows' in flushsnap messages
  ceph: fix dn offset during readdir_prepopulate
  ceph: fix file offset wrapping at 4GB on 32-bit archs
  ceph: fix reconnect encoding for old servers
  ceph: fix pagelist kunmap tail
  ceph: fix null pointer deref on anon root dentry release

* 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intel:
  drm/i915: Hold a reference to the object whilst unbinding the eviction list
  drm/i915,agp/intel: Add second set of PCI-IDs for B43
  drm/i915: Fix Sandybridge fence registers
  drm/i915/crt: Downgrade warnings for hotplug failures
  drm/i915: Ensure that the crtcinfo is populated during mode_fixup()

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  lguest: update comments to reflect LHCALL_LOAD_GDT_ENTRY.
  virtio: console: Prevent userspace from submitting NULL buffers
  virtio: console: Fix poll blocking even though there is data to read

There's a situation where the nohz balancer will try to wake itself:

cpu-x is idle which is also ilb_cpu
got a scheduler tick during idle
and the nohz_kick_needed() in trigger_load_balance() checks for
rq_x->nr_running which might not be zero (because of someone waking a
task on this rq etc) and this leads to the situation of the cpu-x
sending a kick to itself.

And this can cause a lockup.

Avoid this by not marking ourself eligible for kicking.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1284400941.2684.19.camel@sbsiddha-MOBL3.sc.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch adds CPU type detection for dunnington processor (Family 6
/ Model 29) to be identified as core 2 family cpu type (wikipedia
source).

I tested oprofile on Intel(R) Xeon(R) CPU E7440 reporting itself as
model 29, and it runs without an issue.

Spec:

 http://www.intel.com/Assets/en_US/PDF/specupdate/320336.pdfSigned-off-by: NJiri Olsa <jolsa@redhat.com>
Acked-by: NAndi Kleen <ak@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: NRobert Richter <robert.richter@amd.com>

Mike reported a kernel crash when a usb key hotplug is performed while all
kernel thrads are not in a root cgroup and are running in one of the child
cgroups of blkio controller.

	BUG: unable to handle kernel NULL pointer dereference at 0000002c
	IP: [<c11c7b08>] cfq_get_queue+0x232/0x412
	*pde = 00000000
	Oops: 0000 [#1] PREEMPT
	last sysfs file: /sys/devices/pci0000:00/0000:00:1d.7/usb2/2-1/2-1:1.0/host3/scsi_host/host3/uevent

	[..]
	Pid: 30039, comm: scsi_scan_3 Not tainted 2.6.35.2-fg.roam #1 Volvi2                         /Aspire 4315
	EIP: 0060:[<c11c7b08>] EFLAGS: 00010086 CPU: 0
	EIP is at cfq_get_queue+0x232/0x412
	EAX: f705f9c0 EBX: e977abac ECX: 00000000 EDX: 00000000
	ESI: f00da400 EDI: f00da4ec EBP: e977a800 ESP: dff8fd00
	 DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
	Process scsi_scan_3 (pid: 30039, ti=dff8e000 task=f6b6c9a0 task.ti=dff8e000)
	Stack:
	 00000000 00000000 00000001 01ff0000 f00da508 00000000 f00da524 f00da540
	<0> e7994940 dd631750 f705f9c0 e977a820 e977ac44 f00da4d0 00000001 f6b6c9a0
	<0> 00000010 00008010 0000000b 00000000 00000001 e977a800 dd76fac0 00000246
	Call Trace:
	 [<c11c7f10>] ? cfq_set_request+0x228/0x34c
	 [<c11c7ce8>] ? cfq_set_request+0x0/0x34c
	 [<c11bb3b9>] ? elv_set_request+0xf/0x1c
	 [<c11bdd51>] ? get_request+0x1ad/0x22f
	 [<c11bddf2>] ? get_request_wait+0x1f/0x11a
	 [<c11d013b>] ? kvasprintf+0x33/0x3b
	 [<c127b537>] ? scsi_execute+0x1d/0x103
	 [<c127b675>] ? scsi_execute_req+0x58/0x83
	 [<c127c391>] ? scsi_probe_and_add_lun+0x188/0x7c2
	 [<c12718c6>] ? attribute_container_add_device+0x15/0xfa
	 [<c11c95d1>] ? kobject_get+0xf/0x13
	 [<c126d1db>] ? get_device+0x10/0x14
	 [<c127be93>] ? scsi_alloc_target+0x217/0x24d
	 [<c127cbd8>] ? __scsi_scan_target+0x95/0x480
	 [<c10204eb>] ? dequeue_entity+0x14/0x1fe
	 [<c1020491>] ? update_curr+0x165/0x1ab
	 [<c1020491>] ? update_curr+0x165/0x1ab
	 [<c127d00d>] ? scsi_scan_channel+0x4a/0x76
	 [<c127d0b0>] ? scsi_scan_host_selected+0x77/0xad
	 [<c127d13c>] ? do_scan_async+0x0/0x11a
	 [<c127d137>] ? do_scsi_scan_host+0x51/0x56
	 [<c127d13c>] ? do_scan_async+0x0/0x11a
	 [<c127d14a>] ? do_scan_async+0xe/0x11a
	 [<c127d13c>] ? do_scan_async+0x0/0x11a
	 [<c10354c5>] ? kthread+0x5e/0x63
	 [<c1035467>] ? kthread+0x0/0x63
	 [<c1002af6>] ? kernel_thread_helper+0x6/0x10
	Code: 44 24 1c 54 83 44 24 18 54 83 fa 03 75 94 8b 06 c7 86 64 02 00 00 01 00 00 00 83 e0 03 09 f0 89 06 8b 44 24 28 8b 90 58 01 00 00 <8b> 42 2c 85 c0 75 03 8b 42 08 8d 54 24 48 52 8d 4c 24 50 51 68
	EIP: [<c11c7b08>] cfq_get_queue+0x232/0x412 SS:ESP 0068:dff8fd00
	CR2: 000000000000002c
	---[ end trace 9a88306573f69b12 ]---

The problem here is that we don't have bdi->dev information available when
thread does some IO.  Hence when dev_name() tries to access bdi->dev, it
crashes.

This problem does not happen if kernel threads are in root group as root
group is statically allocated at device initialization time and we don't
hit this piece of code.

Fix it by delaying the filling of major and minor number information of
device in blk_group.  Initially a blk_group is created with 0 as device
information and this information is filled later once some more IO comes
in from same group.
Reported-by: NMike Kazantsev <mk.fraggod@gmail.com>
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

This bug was introduced in 7b6d91da
"block: unify flags for struct bio and struct request"

Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

The "h->scatter_list" is allocated inside a for loop.  If any of those
allocations fail, then the rest of the list is uninitialized data.  When
we free it we should start from the top and free backwards so that we
don't call kfree() on uninitialized pointers.

Also if the allocation for "h->scatter_list" fails then we would get an
Oops here.  I should have noticed this when I send: 4ee69851 "cciss:
handle allocation failure."  but I didn't.  Sorry about that.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

If another cpu does a very wide munmap() on the signal frame area,
it can tear down the page table hierarchy from underneath us.

Borrow an idea from the 64-bit fault path's get_user_insn(), and
disable cross call interrupts during the page table traversal
to lock them in place while we operate.
Reported-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We used to have a hypercall which reloaded the entire GDT, then we
switched to one which loaded a single entry (to match the IDT code).

Some comments were not updated, so fix them.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Reported by: Eviatar Khen <eviatarkhen@gmail.com>

A userspace could submit a buffer with 0 length to be written to the
host.  Prevent such a situation.

This was not needed previously, but recent changes in the way write()
works exposed this condition to trigger a virtqueue event to the host,
causing a NULL buffer to be sent across.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
CC: stable@kernel.org

I found this while working on a Linux agent for spice, the symptom I was
seeing was select blocking on the spice vdagent virtio serial port even
though there were messages queued up there.

virtio_console's port_fops_poll checks port->inbuf != NULL to determine
if read won't block. However if an application reads enough bytes from
inbuf through port_fops_read, to empty the current port->inbuf,
port->inbuf will be NULL even though there may be buffers left in the
virtqueue.

This causes poll() to block even though there is data to be read,
this patch fixes this by using will_read_block(port) instead of the
port->inbuf != NULL check.
Signed-off-By: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6:
  Staging: vt6655: fix buffer overflow
  Revert: "Staging: batman-adv: Adding netfilter-bridge hooks"