yield_to_task_fair() has code to resched the CPU of yielding task when the
intention is to resched the CPU of the task that is being yielded to.

Change here fixes the problem and also makes the resched conditional on
rq != p_rq.
Signed-off-by: Venkatesh Pallipadi <venki@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299025701-22168-1-git-send-email-venki@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

The current scheduler implementation returns -EPERM when trying to
change from SCHED_IDLE to SCHED_OTHER or SCHED_BATCH. Since SCHED_IDLE
is considered to be a nice 20 on steroids, changing to another policy
should be allowed provided the RLIMIT_NICE is accounted for.

This patch allows the following test-case to pass with RLIMIT_NICE=40,
but still fail with RLIMIT_NICE=10 when the calling process is run
from a typical shell (nice 0, or 20 in rlimit terms).

int main()
{
	int ret;
	struct sched_param sp;
	sp.sched_priority = 0;

	/* switch to SCHED_IDLE */
	ret = sched_setscheduler(0, SCHED_IDLE, &sp);
	printf("setscheduler IDLE: %d\n", ret);
	if (ret) return ret;

	/* switch back to SCHED_OTHER */
	ret = sched_setscheduler(0, SCHED_OTHER, &sp);
	printf("setscheduler OTHER: %d\n", ret);

	return ret;
}

 $ ulimit -e
 40
 $ ./test
 setscheduler IDLE: 0
 setscheduler OTHER: 0

 $ ulimit -e 10
 $ ulimit -e
 10
 $ ./test
 setscheduler IDLE: 0
 setscheduler OTHER: -1
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Richard Purdie <richard.purdie@linuxfoundation.org>
LKML-Reference: <4D657BEE.4040608@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Perform the test for SCHED_IDLE before testing for SCHED_BATCH (and
ensure idle tasks don't preempt idle tasks) so the non-interactive,
but still important, SCHED_BATCH tasks will run in favor of the very
low priority SCHED_IDLE tasks.
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
Cc: Richard Purdie <richard.purdie@linuxfoundation.org>
LKML-Reference: <1298408674-3130-2-git-send-email-dvhart@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Merge reason: Add fixes before applying dependent patches.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

The current sched rt code is broken when it comes to hierarchical
scheduling, this patch fixes two problems

1. It adds redundant enqueuing (harmless) when it finds a queue
   has tasks enqueued, but it has no run time and it is not
   throttled.

2. The most important change is in sched_rt_rq_enqueue/dequeue.
   The code just picks the rt_rq belonging to the current cpu
   on which the period timer runs, the patch fixes it, so that
   the correct rt_se is enqueued/dequeued.

Tested with a simple hierarchy

/c/d, c and d assigned similar runtimes of 50,000 and a while
1 loop runs within "d". Both c and d get throttled, without
the patch, the task just stops running and never runs (depends
on where the sched_rt b/w timer runs). With the patch, the
task is throttled and runs as expected.

[ bharata, suggestions on how to pick the rt_se belong to the
  rt_rq and correct cpu ]
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@kernel.org
LKML-Reference: <20110303113435.GA2868@balbir.in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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:
  DNS: Fix a NULL pointer deref when trying to read an error key [CVE-2011-1076]

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (42 commits)
  MAINTAINERS: Add Andy Gospodarek as co-maintainer.
  r8169: disable ASPM
  RxRPC: Fix v1 keys
  AF_RXRPC: Handle receiving ACKALL packets
  cnic: Fix lost interrupt on bnx2x
  cnic: Prevent status block race conditions with hardware
  net: dcbnl: check correct ops in dcbnl_ieee_set()
  e1000e: disable broken PHY wakeup for ICH10 LOMs, use MAC wakeup instead
  igb: fix sparse warning
  e1000: fix sparse warning
  netfilter: nf_log: avoid oops in (un)bind with invalid nfproto values
  dccp: fix oops on Reset after close
  ipvs: fix dst_lock locking on dest update
  davinci_emac: Add Carrier Link OK check in Davinci RX Handler
  bnx2x: update driver version to 1.62.00-6
  bnx2x: properly calculate lro_mss
  bnx2x: perform statistics "action" before state transition.
  bnx2x: properly configure coefficients for MinBW algorithm (NPAR mode).
  bnx2x: Fix ethtool -t link test for MF (non-pmf) devices.
  bnx2x: Fix nvram test for single port devices.
  ...

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: kill loop_mutex
  blktrace: Remove blk_fill_rwbs_rq.
  block: blk-flush shouldn't call directly into q->request_fn() __blk_run_queue()
  block: add @force_kblockd to __blk_run_queue()
  block: fix kernel-doc format for blkdev_issue_zeroout
  blk-throttle: Do not use kblockd workqueue for throtl work

* 'i_nlink' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  hfs: fix rename() over non-empty directory
  udf: fix i_nlink limit
  fix reiserfs mkdir() breakage
  exofs: i_nlink races in rename()
  nilfs2: i_nlink races in rename()
  minix: i_nlink races in rename()
  ufs: i_nlink races in rename()
  sysv: i_nlink races in rename()

When a DNS resolver key is instantiated with an error indication, attempts to
read that key will result in an oops because user_read() is expecting there to
be a payload - and there isn't one [CVE-2011-1076].

Give the DNS resolver key its own read handler that returns the error cached in
key->type_data.x[0] as an error rather than crashing.

Also make the kenter() at the beginning of dns_resolver_instantiate() limit the
amount of data it prints, since the data is not necessarily NUL-terminated.

The buggy code was added in:

	commit 4a2d7892
	Author: Wang Lei <wang840925@gmail.com>
	Date:   Wed Aug 11 09:37:58 2010 +0100
	Subject: DNS: If the DNS server returns an error, allow that to be cached [ver #2]

This can trivially be reproduced by any user with the following program
compiled with -lkeyutils:

	#include <stdlib.h>
	#include <keyutils.h>
	#include <err.h>
	static char payload[] = "#dnserror=6";
	int main()
	{
		key_serial_t key;
		key = add_key("dns_resolver", "a", payload, sizeof(payload),
			      KEY_SPEC_SESSION_KEYRING);
		if (key == -1)
			err(1, "add_key");
		if (keyctl_read(key, NULL, 0) == -1)
			err(1, "read_key");
		return 0;
	}

What should happen is that keyctl_read() reports error 6 (ENXIO) to the user:

	dns-break: read_key: No such device or address

but instead the kernel oopses.

This cannot be reproduced with the 'keyutils add' or 'keyutils padd' commands
as both of those cut the data down below the NUL termination that must be
included in the data.  Without this dns_resolver_instantiate() will return
-EINVAL and the key will not be instantiated such that it can be read.

The oops looks like:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: [<ffffffff811b99f7>] user_read+0x4f/0x8f
PGD 3bdf8067 PUD 385b9067 PMD 0
Oops: 0000 [#1] SMP
last sysfs file: /sys/devices/pci0000:00/0000:00:19.0/irq
CPU 0
Modules linked in:

Pid: 2150, comm: dns-break Not tainted 2.6.38-rc7-cachefs+ #468                  /DG965RY
RIP: 0010:[<ffffffff811b99f7>]  [<ffffffff811b99f7>] user_read+0x4f/0x8f
RSP: 0018:ffff88003bf47f08  EFLAGS: 00010246
RAX: 0000000000000001 RBX: ffff88003b5ea378 RCX: ffffffff81972368
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003b5ea378
RBP: ffff88003bf47f28 R08: ffff88003be56620 R09: 0000000000000000
R10: 0000000000000395 R11: 0000000000000002 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffffffffffa1
FS:  00007feab5751700(0000) GS:ffff88003e000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 000000003de40000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process dns-break (pid: 2150, threadinfo ffff88003bf46000, task ffff88003be56090)
Stack:
 ffff88003b5ea378 ffff88003b5ea3a0 0000000000000000 0000000000000000
 ffff88003bf47f68 ffffffff811b708e ffff88003c442bc8 0000000000000000
 00000000004005a0 00007fffba368060 0000000000000000 0000000000000000
Call Trace:
 [<ffffffff811b708e>] keyctl_read_key+0xac/0xcf
 [<ffffffff811b7c07>] sys_keyctl+0x75/0xb6
 [<ffffffff81001f7b>] system_call_fastpath+0x16/0x1b
Code: 75 1f 48 83 7b 28 00 75 18 c6 05 58 2b fb 00 01 be bb 00 00 00 48 c7 c7 76 1c 75 81 e8 13 c2 e9 ff 4c 8b b3 e0 00 00 00 4d 85 ed <41> 0f b7 5e 10 74 2d 4d 85 e4 74 28 e8 98 79 ee ff 49 39 dd 48
RIP  [<ffffffff811b99f7>] user_read+0x4f/0x8f
 RSP <ffff88003bf47f08>
CR2: 0000000000000010
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
cc: Wang Lei <wang840925@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>

Acked-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: zero proper structure size for geometry calls

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: fix regression that i-flag is not set on changeless checkpoints

For some time is known that ASPM is causing troubles on r8169, i.e. make
device randomly stop working without any errors in dmesg.

Currently Tomi Leppikangas reports that system with r8169 device hangs
with MCE errors when ASPM is enabled:
https://bugzilla.redhat.com/show_bug.cgi?id=642861#c4

Lets disable ASPM for r8169 devices at all, to avoid problems with
r8169 PCIe devices at least for some users.
Reported-by: Tomi Leppikangas <tomi.leppikangas@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Following steps lead to deadlock in kernel:

dd if=/dev/zero of=img bs=512 count=1000
losetup -f img
mkfs.ext2 /dev/loop0
mount -t ext2 -o loop /dev/loop0 mnt
umount mnt/

Stacktrace:
[<c102ec04>] irq_exit+0x36/0x59
[<c101502c>] smp_apic_timer_interrupt+0x6b/0x75
[<c127f639>] apic_timer_interrupt+0x31/0x38
[<c101df88>] mutex_spin_on_owner+0x54/0x5b
[<fe2250e9>] lo_release+0x12/0x67 [loop]
[<c10c4eae>] __blkdev_put+0x7c/0x10c
[<c10a4da5>] fput+0xd5/0x1aa
[<fe2250cf>] loop_clr_fd+0x1a9/0x1b1 [loop]
[<fe225110>] lo_release+0x39/0x67 [loop]
[<c10c4eae>] __blkdev_put+0x7c/0x10c
[<c10a59d9>] deactivate_locked_super+0x17/0x36
[<c10b6f37>] sys_umount+0x27e/0x2a5
[<c10b6f69>] sys_oldumount+0xb/0xe
[<c1002897>] sysenter_do_call+0x12/0x26
[<ffffffff>] 0xffffffff

Regression since 2a48fc0a, which introduced the private
loop_mutex as part of the BKL removal process.

As per [1], the mutex can be safely removed.

[1] http://www.gossamer-threads.com/lists/linux/kernel/1341930

Addresses: https://bugzilla.novell.com/show_bug.cgi?id=669394
Addresses: https://bugzilla.kernel.org/show_bug.cgi?id=29172Signed-off-by: Petr Uzel <petr.uzel@suse.cz>
Cc: stable@kernel.org
Reviewed-by: Nikanth Karthikesan <knikanth@suse.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

If we enable trace events to trace block actions, We use
blk_fill_rwbs_rq to analyze the corresponding actions
in request's cmd_flags, but we only choose the minor 2 bits
from it, so most of other flags(e.g, REQ_SYNC) are missing.
For example, with a sync write we get:
write_test-2409  [001]   160.013869: block_rq_insert: 3,64 W 0 () 258135 + =
8 [write_test]

Since now we have integrated the flags of both bio and request,
it is safe to pass rq->cmd_flags directly to blk_fill_rwbs and
blk_fill_rwbs_rq isn't needed any more.

With this patch, after a sync write we get:
write_test-2417  [000]   226.603878: block_rq_insert: 3,64 WS 0 () 258135 +=
 8 [write_test]
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

merge hfs_unlink() and hfs_rmdir(), while we are at it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

(256 << sizeof(x)) - 1 is not the maximal possible value of x...
In reality, the maximal allowed value for UDF FileLinkCount is
65535.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

if directory has so many subdirectories that its link count is set
to 1 (i.e. "can't tell accurately") and reiserfs_new_inode() fails,
we shouldn't decrement the parent's link count in cleanup path;
that's what DEC_DIR_INODE_NLINK() is for.  As it is, we end up
with parent suddenly getting zero i_nlink, with very unpleasant
effects.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

commit 33941284 (RxRPC: Allow key payloads to be passed in XDR form)
broke klog for me. I notice the v1 key struct had a kif_version field
added:

-struct rxkad_key {
-       u16     security_index;         /* RxRPC header security index */
-       u16     ticket_len;             /* length of ticket[] */
-       u32     expiry;                 /* time at which expires */
-       u32     kvno;                   /* key version number */
-       u8      session_key[8];         /* DES session key */
-       u8      ticket[0];              /* the encrypted ticket */
-};

+struct rxrpc_key_data_v1 {
+       u32             kif_version;            /* 1 */
+       u16             security_index;
+       u16             ticket_length;
+       u32             expiry;                 /* time_t */
+       u32             kvno;
+       u8              session_key[8];
+       u8              ticket[0];
+};

However the code in rxrpc_instantiate strips it away:

	data += sizeof(kver);
	datalen -= sizeof(kver);

Removing kif_version fixes my problem.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The OpenAFS server is now sending ACKALL packets, so we need to handle them.
Otherwise we report a protocol error and abort.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/i915: fix memory corruption with GM965 and >4GB RAM

* 'devicetree/merge' of git://git.secretlab.ca/git/linux-2.6:
  of/promtree: allow DT device matching by fixing 'name' brokenness (v5)
  x86: OLPC: have prom_early_alloc BUG rather than return NULL
  of/flattree: Drop an uninteresting message to pr_debug level
  of: Add missing of_address.h to xilinx ehci driver

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha-2.6:
  alpha: Enable GENERIC_HARDIRQS_NO_DEPRECATED
  alpha: irq: Convert affinity to use irq_data
  alpha: irq: Remove pointless irq status manipulation
  alpha: titan: Convert irq_chip functions
  alpha: takara: Convert irq_chip functions
  alpha: sable: Convert irq_chip functions
  alpha: rx164: Convert irq_chip functions
  alpha: noritake: Convert irq_chip functions
  alpha: rawhide: Convert irq_chip functions
  alpha: mikasa: Convert irq_chip functions
  alpha: marvel: Convert irq_chip functions
  alpha: eiger: Convert irq_chip functions
  alpha: eb64p: Convert irq_chip functions
  alpha: dp264: Convert irq_chip functions
  alpha: cabriolet: Convert irq_chip functions
  alpha: i8259, alcor, jensen wildfire: Convert irq_chip
  alpha: srm: Convert irq_chip functions
  alpha: Pyxis convert irq_chip functions
  Fix typo in call to irq_to_desc()

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
  mfd: Avoid tps6586x burst writes
  mfd: Don't suspend WM8994 if the CODEC is not suspended
  mfd: Fix DaVinci voice codec device name
  mfd: Fix NULL pointer due to non-initialized ucb1x00-ts absinfo
  mfd: Fix ASIC3 build with GENERIC_HARDIRQS_NO_DEPRECATED

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  ext2: Fix link count corruption under heavy link+rename load

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] p4-clockmod: print EST-capable warning message only once
  [CPUFREQ] fix BUG on cpufreq policy init failure
  [CPUFREQ] Fix another notifier leak in powernow-k8.
  [CPUFREQ] Missing "unregister_cpu_notifier" in powernow-k8.c

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Fix call to flush_ptrace_hw_breakpoint()
  powerpc/kexec: Restore ppc_md.machine_kexec
  powerpc/mm: Make hpte_need_flush() safe for preemption

* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
  intel_idle: disable Atom/Lincroft HW C-state auto-demotion
  intel_idle: disable NHM/WSM HW C-state auto-demotion

We service 2 queues (kcq1 and kcq2) in cnic_service_bnx2x_bh().  If
the status block index has changed when servicing the kcq2, we must
go back and check kcq1.  The latest status block index will be used
to acknowledge the interrupt, and without looping back to check kcq1,
we may miss events on kcq1.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The status block index is used to acknowledge interrupt events and must
be read before checking for the interrupt events, so we need to add rmb()
to guarantee that.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
  ACPI / ACPICA: Implicit notify for multiple devices
  ACPI / debugfs: Fix buffer overflows, double free

The incorrect ops routine was being tested for in
DCB_ATTR_IEEE_PFC attributes. This patch corrects
it.

Currently, every driver implementing ieee_setets also
implements ieee_setpfc so this bug is not actualized
yet.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit e2f2a93b, "of/promtree: add package-to-path support to pdt"
changed dp->name from using the 'name' property to using
package-to-path.  This fixed /proc/device-tree creation by eliminating
conflicts between names (the 'name' property provides names like
'battery', whereas package-to-path provides names like
'/foo/bar/battery@0', which we stripped to 'battery@0').  However, it
also breaks of_device_id table matching.

The fix that we _really_ wanted was to keep dp->name based upon
the name property ('battery'), but based dp->full_name upon
package-to-path ('battery@0').  This patch does just that.

This changes all users (except SPARC) of promtree to use the full
result from package-to-path for full_name, rather than stripping the
directory out.  In practice, the strings end up being exactly the
same; this change saves time, code, and memory.

SPARC continues to use the existing build_path_component() code.

v2: combine two patches and revert of_pdt_node_name to original version
v3: use dp->phandle instead of passing around node
v4: warn/bail out for non-sparc archs if pkg2path is not set
v5: split of_pdt_build_full_name into sparc & non-sparc versions
v6: Pass NULL to pkg2path before buf gets assigned.
    Drop check for pkg2path hook on each and every node.
v7: Don't BUG() when unable to get the full_path; create a
    known-unique name instead.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>