Commit 5a6fe125 brought hugetlbfs more
in line with the core VM by obeying VM_NORESERVE and not reserving
hugepages for both shared and private mappings when [SHM|MAP]_NORESERVE
are specified.  However, it is still taking filesystem quota
unconditionally.

At fault time, if there are no reserves and attempt is made to allocate
the page and account for filesystem quota.  If either fail, the fault
fails.  The impact is that quota is getting accounted for twice.  This
patch partially reverts 5a6fe125.  To
help prevent this mistake happening again, it improves the documentation
of hugetlb_reserve_pages()
Reported-by: NAndy Whitcroft <apw@canonical.com>
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Acked-by: NAndy Whitcroft <apw@canonical.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.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: revert recent sync wakeup changes

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

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  timers: fix TIMER_ABSTIME for process wide cpu timers
  timers: split process wide cpu clocks/timers, fix
  x86: clean up hpet timer reinit
  timers: split process wide cpu clocks/timers, remove spurious warning
  timers: split process wide cpu clocks/timers
  signal: re-add dead task accumulation stats.
  x86: fix hpet timer reinit for x86_64
  sched: fix nohz load balancer on cpu offline

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  ptrace, x86: fix the usage of ptrace_fork()
  i8327: fix outb() parameter order
  x86: fix math_emu register frame access
  x86: math_emu info cleanup
  x86: include correct %gs in a.out core dump
  x86, vmi: put a missing paravirt_release_pmd in pgd_dtor
  x86: find nr_irqs_gsi with mp_ioapic_routing
  x86: add clflush before monitor for Intel 7400 series
  x86: disable intel_iommu support by default
  x86: don't apply __supported_pte_mask to non-present ptes
  x86: fix grammar in user-visible BIOS warning
  x86/Kconfig.cpu: make Kconfig help readable in the console
  x86, 64-bit: print DMI info in the oops trace

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

* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing, x86: fix constraint for parent variable
  tracing, x86: fix fixup section to return to original code
  profiling: fix broken profiling regression

* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] Update default configuration.
  [S390] dasd: fix race in dasd timer handling
  [S390] dasd: bus_id -> dev_name() conversion.
  [S390] Fix init irq proc build break.
  [S390] vdso: fix per cpu vdso pointer in lowcore

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/mm: Fix _PAGE_COHERENT support on classic ppc32 HW

Intel reported a 10% regression (mysql+sysbench) on a 16-way machine
with these patches:

  1596e297: sched: symmetric sync vs avg_overlap
  d942fb6c: sched: fix sync wakeups

Revert them.
Reported-by: N"Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Bisected-by: NLin Ming <ming.m.lin@intel.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The POSIX timer interface allows for absolute time expiry values through the
TIMER_ABSTIME flag, therefore we have to synchronize the timer to the clock
every time we start it.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

To decrease the chance of a missed enable, always enable the timer when we
sample it, we'll always disable it when we find that there are no active timers
in the jiffy tick.

This fixes a flood of warnings reported by Mike Galbraith.
Reported-by: NMike Galbraith <efault@gmx.de>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

In dasd_device_set_timer and dasd_block_set_timer we interpret the
return value of mod_timer in a wrong way. If the timer expires in
the small window between our check of timer_pending and the call to
mod_timer, then the timer will be set, mod_timer returns zero and
we will call add_timer for a timer that is already pending.
As del_timer and mod_timer do all the necessary checking themselves,
we can simplify our code and remove the race a the same time.
Signed-off-by: NStefan Weinhuber <wein@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

bus_id usage crept in again; fix it.
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

Embed init_irq_proc(s390) within CONFIG_PROC_FS to fix a build break.

Signed-off-by : Sachin Sant <sachinp@in.ibm.com>

The vdso_per_cpu_data entry in the lowcore structure uses __u32
instead of __u64. If the data page is above 4GB the pointer is
truncated and the kernel crashes.
Reported-by: NMijo Safradin <mijo@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

I noticed by pure accident we have ptrace_fork() and friends. This was
added by "x86, bts: add fork and exit handling", commit
bf53de90.

I can't test this, ds_request_bts() returns -EOPNOTSUPP, but I strongly
believe this needs the fix. I think something like this program

	int main(void)
	{
		int pid = fork();

		if (!pid) {
			ptrace(PTRACE_TRACEME, 0, NULL, NULL);
			kill(getpid(), SIGSTOP);
			fork();
		} else {
			struct ptrace_bts_config bts = {
				.flags = PTRACE_BTS_O_ALLOC,
				.size  = 4 * 4096,
			};

			wait(NULL);

			ptrace(PTRACE_SETOPTIONS, pid, NULL, PTRACE_O_TRACEFORK);
			ptrace(PTRACE_BTS_CONFIG, pid, &bts, sizeof(bts));
			ptrace(PTRACE_CONT, pid, NULL, NULL);

			sleep(1);
		}

		return 0;
	}

should crash the kernel.

If the task is traced by its natural parent ptrace_reparented() returns 0
but we should clear ->btsxxx anyway.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Acked-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The constraint used for retrieving and restoring the parent function
pointer is incorrect. The parent variable is a pointer, and the
address of the pointer is modified by the asm statement and not
the pointer itself. It is incorrect to pass it in as an output
constraint since the asm will never update the pointer.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Merge branch 'tip/tracing/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/urgent

The following commit:

commit 64b3d0e8
Author: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date:   Thu Dec 18 19:13:51 2008 +0000

    powerpc/mm: Rework usage of _PAGE_COHERENT/NO_CACHE/GUARDED

broke setting of the _PAGE_COHERENT bit in the PPC HW PTE.  Since we now
actually set _PAGE_COHERENT in the Linux PTE we shouldn't be clearing it
out before we propogate it to the PPC HW PTE.
Reported-by: NMartyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

* master.kernel.org:/home/rmk/linux-2.6-arm:
  [ARM] AACI: timeout will reach -1
  [ARM] Storage class should be before const qualifier
  [ARM] pxa: stop and disable IRQ for each DMA channels at startup
  [ARM] pxa: make more SSCR0 bit definitions visible on multiple processors
  [ARM] pxa: fix missing of __REG() definition for ac97 registers access
  [ARM] pxa: fix NAND and MMC clock initialization for pxa3xx

Fix regression due to 5a6fe125,
"Do not account for the address space used by hugetlbfs using VM_ACCOUNT"
which added an argument to the function hugetlb_file_setup() but not to
the macro hugetlb_file_setup().
Reported-by: NChris Clayton <chris2553@googlemail.com>
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Add missing sparsemem.h include
  powerpc/pci: mmap anonymous memory when legacy_mem doesn't exist
  powerpc/cell: Add missing #include for oprofile
  powerpc/ftrace: Fix math to calculate offset in TOC
  powerpc: Don't emulate mr. instructions
  powerpc/fsl-booke: Fix mapping functions to use phys_addr_t
  arch/powerpc: Eliminate double sizeof
  powerpc/cpm2: Fix set interrupt type
  powerpc/83xx: Fix TSEC0 workability on MPC8313E-RDB boards
  powerpc/83xx: Fix missing #{address,size}-cells in mpc8313erdb.dts
  powerpc/83xx: Build breakage for CONFIG_PM but no CONFIG_SUSPEND

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc64: Fix probe_kernel_{read,write}().
  sparc64: Kill .fixup section bloat.
  sparc64: Don't hook up pcr_ops on spitfire chips.
  sparc64: Call dump_stack() in die_nmi().

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (23 commits)
  bridge: Fix LRO crash with tun
  IPv6: fix to set device name when new IPv6 over IPv6 tunnel device is created.
  gianfar: Fix boot hangs while bringing up gianfar ethernet
  netfilter: xt_sctp: sctp chunk mapping doesn't work
  netfilter: ctnetlink: fix echo if not subscribed to any multicast group
  netfilter: ctnetlink: allow changing NAT sequence adjustment in creation
  netfilter: nf_conntrack_ipv6: don't track ICMPv6 negotiation message
  netfilter: fix tuple inversion for Node information request
  netxen: fix msi-x interrupt handling
  de2104x: force correct order when writing to rx ring
  tun: Fix unicast filter overflow
  drivers/isdn: introduce missing kfree
  drivers/atm: introduce missing kfree
  sunhme: Don't match PCI devices in SBUS probe.
  9p: fix endian issues [attempt 3]
  net_dma: call dmaengine_get only if NET_DMA enabled
  3c509: Fix resume from hibernation for PnP mode.
  sungem: Soft lockup in sungem on Netra AC200 when switching interface up
  RxRPC: Fix a potential NULL dereference
  r8169: Don't update statistics counters when interface is down
  ...

When overcommit is disabled, the core VM accounts for pages used by anonymous
shared, private mappings and special mappings. It keeps track of VMAs that
should be accounted for with VM_ACCOUNT and VMAs that never had a reserve
with VM_NORESERVE.

Overcommit for hugetlbfs is much riskier than overcommit for base pages
due to contiguity requirements. It avoids overcommiting on both shared and
private mappings using reservation counters that are checked and updated
during mmap(). This ensures (within limits) that hugepages exist in the
future when faults occurs or it is too easy to applications to be SIGKILLed.

As hugetlbfs makes its own reservations of a different unit to the base page
size, VM_ACCOUNT should never be set. Even if the units were correct, we would
double account for the usage in the core VM and hugetlbfs. VM_NORESERVE may
be set because an application can request no reserves be made for hugetlbfs
at the risk of getting killed later.

With commit fc8744ad, VM_NORESERVE and
VM_ACCOUNT are getting unconditionally set for hugetlbfs-backed mappings. This
breaks the accounting for both the core VM and hugetlbfs, can trigger an
OOM storm when hugepage pools are too small lockups and corrupted counters
otherwise are used. This patch brings hugetlbfs more in line with how the
core VM treats VM_NORESERVE but prevents VM_ACCOUNT being set.
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Impact: fix to prevent a kernel crash on fault

If for some reason the pointer to the parent function on the
stack takes a fault, the fix up code will not return back to
the original faulting code. This can lead to unpredictable
results and perhaps even a kernel panic.

A fault should not happen, but if it does, we should simply
disable the tracer, warn, and continue running the kernel.
It should not lead to a kernel crash.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>

In i8237A_resume(), when resetting the DMA controller, the parameters to
dma_outb() were mixed up.
Signed-off-by: NClemens Ladisch <clemens@ladisch.de>
[ cleaned up the file a tiny bit. ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With a postfix decrement the timeout will reach -1 rather than 0,
so the warning will not be issued.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The C99 specification states in section 6.11.5:

The placement of a storage-class specifier other than at the beginning of the
declaration specifiers in a declaration is an obsolescent feature.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/powerpc/platforms/pseries/hotplug-memory.c uses
remove_section_mapping() but doesn't include sparsemem.h which defines
it.  This can cause compilation fails for some configs.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

The new legacy_mem file in sysfs is causing problems with X on machines
that don't support legacy memory access. The way I initially implemented
it, we would fail with -ENXIO when trying to mmap it, thus exposing to
X that we do support the API but there is no legacy memory.

Unfortunately, X poor error handling is causing it to fail to start when
it gets this error.

This implements a workaround hack that instead maps anonymous memory
instead (using shmem if VM_SHARED is set, just like /dev/zero does).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/oprofile/cell/spu_profiler.c is missing a asm/time.h
include which is required for ppc_proc_freq.  This can cause compile
failures for some config combinations.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Impact: fix dynamic ftrace with large modules in PPC64

The math to calculate the offset into the TOC that is taken from reading
the trampoline is incorrect. The bottom half of the offset is a signed
extended short. The current code was using an OR to create the offset
when it should have been using an addition.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Acked-by: NGeoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Currently emulate_step() emulates mr. instructions without updating cr0
and this can be disastrous. Don't emulate mr.

This bug has been around for a while, but I am not sure if its a worthy
-stable candidate. I'll leave it to Ben do decide.
Signed-off-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Fixed v_mapped_by_tlbcam() and p_mapped_by_tlbcam() to use phys_addr_t
instead of unsigned long.  In 36-bit physical mode we really need these
functions to deal with phys_addr_t when trying to match a physical
address or when returning one.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Impact: fix broken /proc/profile on UP machines

Commit c309b917 "cpumask: convert
kernel/profile.c" broke profiling.  prof_cpu_mask was previously
initialized to CPU_MASK_ALL, but left uninitialized in that commit.
We need to copy cpu_possible_mask (cpu_online_mask is not enough).
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

do_device_not_available() is the handler for #NM and it declares that
it takes a unsigned long and calls math_emu(), which takes a long
argument and surprisingly expects the stack frame starting at the zero
argument would match struct math_emu_info, which isn't true regardless
of configuration in the current code.

This patch makes do_device_not_available() take struct pt_regs like
other exception handlers and initialize struct math_emu_info with
pointer to it and pass pointer to the math_emu_info to math_emulate()
like normal C functions do.  This way, unless gcc makes a copy of
struct pt_regs in do_device_not_available(), the register frame is
correctly accessed regardless of kernel configuration or compiler
used.

This doesn't fix all math_emu problems but it at least gets it
somewhat working.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

> Kernel BUG at drivers/net/tun.c:444
> invalid opcode: 0000 [1] SMP
> last sysfs file: /class/net/lo/ifindex
> CPU 0
> Modules linked in: tun ipt_MASQUERADE iptable_nat ip_nat xt_state ip_conntrack
> nfnetlink ipt_REJECT xt_tcpudp iptable_filter d
> Pid: 6912, comm: qemu-kvm Tainted: G      2.6.18-128.el5 #1
> RIP: 0010:[<ffffffff886f57b0>]  [<ffffffff886f57b0>]
> :tun:tun_chr_readv+0x2b1/0x3a6
> RSP: 0018:ffff8102202c5e48  EFLAGS: 00010246
> RAX: 0000000000000000 RBX: ffff8102202c5e98 RCX: 0000000004010000
> RDX: ffff810227063680 RSI: ffff8102202c5e9e RDI: ffff8102202c5e92
> RBP: 0000000000010ff6 R08: 0000000000000000 R09: 0000000000000001
> R10: ffff8102202c5e94 R11: 0000000000000202 R12: ffff8102275357c0
> R13: ffff81022755e500 R14: 0000000000000000 R15: ffff8102202c5ef8
> FS:  00002ae4398db980(0000) GS:ffffffff803ac000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> CR2: 00002ae4ab514000 CR3: 0000000221344000 CR4: 00000000000026e0
> Process qemu-kvm (pid: 6912, threadinfo ffff8102202c4000, task
> ffff81022e58d820)
> Stack:  00000000498735cb ffff810229d1a3c0 0000000000000000 ffff81022e58d820
>  ffffffff8008a461 ffff81022755e528 ffff81022755e528 ffffffff8009f925
>  000005ea05ea0000 ffff8102209d0000 00001051143e1600 ffffffff8003c00e
> Call Trace:
>  [<ffffffff8008a461>] default_wake_function+0x0/0xe
>  [<ffffffff8009f925>] enqueue_hrtimer+0x55/0x70
>  [<ffffffff8003c00e>] hrtimer_start+0xbc/0xce
>  [<ffffffff886f58bf>] :tun:tun_chr_read+0x1a/0x1f
>  [<ffffffff8000b3f3>] vfs_read+0xcb/0x171
>  [<ffffffff800117d4>] sys_read+0x45/0x6e
>  [<ffffffff8005d116>] system_call+0x7e/0x83
>
>
> Code: 0f 0b 68 40 62 6f 88 c2 bc 01 f6 42 0a 08 74 0c 80 4c 24 41
> RIP  [<ffffffff886f57b0>] :tun:tun_chr_readv+0x2b1/0x3a6
>  RSP <ffff8102202c5e48>
>  <0>Kernel panic - not syncing: Fatal exception

This crashed when an LRO packet generated by bnx2x reached a
tun device through the bridge.  We're supposed to drop it at
the bridge.  However, because the check was placed in br_forward
instead of __br_forward, it's only effective if we are sending
the packet through a single port.

This patch fixes it by moving the check into __br_forward.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the user creates IPv6 over IPv6 tunnel, the device name created
by the kernel isn't set to t->parm.name, which is referred as the
result of ioctl().
Signed-off-by: NNoriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ira Snyder found that commit 8c7396ae
"gianfar: Merge Tx and Rx interrupt for scheduling clean up ring" can
cause hangs. It's because there was removed clearing of interrupts in
gfar_schedule_cleanup() (which is called by an interrupt handler) in
case when netif scheduling has been disabled. This patch brings back
this action and a comment.
Reported-by: NIra Snyder <iws@ovro.caltech.edu>
Reported-by: NPeter Korsgaard <jacmet@sunsite.dk>
Bisected-by: NIra Snyder <iws@ovro.caltech.edu>
Tested-by: NPeter Korsgaard <jacmet@sunsite.dk>
Tested-by: NIra Snyder <iws@ovro.caltech.edu>
Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>