Currently on unmount if we are mounted R/W, we first write the superblock to
the media if it is dirty, and then write it again, which is not optimal. This
patch makes ext2 write the superblock on unmount less times.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Commit 00eacd66 ("ext3: make ext3 mount default to barrier=1") changed
the default barrier mount option for ext3.  The documentation needs to
be updated, so this patch does that.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>

max_debt, involved variables and calculations
are no longer needed, clean them up.
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Currently we write out all journal buffers in WRITE_SYNC mode. This improves
performance for fsync heavy workloads but hinders performance when writes
are mostly asynchronous, most noticably it slows down readers and users
complain about slow desktop response etc.

So submit writes as asynchronous in the normal case and only submit writes as
WRITE_SYNC if we detect someone is waiting for current transaction commit.

I've gathered some numbers to back this change. The first is the read latency
test. It measures time to read 1 MB after several seconds of sleeping in
presence of streaming writes.

Top 10 times (out of 90) in us:
Before		After
2131586		697473
1709932		557487
1564598		535642
1480462		347573
1478579		323153
1408496		222181
1388960		181273
1329565		181070
1252486		172832
1223265		172278

Average:
619377		82180

So the improvement in both maximum and average latency is massive.

I've measured fsync throughput by:
fs_mark -n 100 -t 1 -s 16384 -d /mnt/fsync/ -S 1 -L 4

in presence of streaming reader. The numbers (fsyncs/s) are:
Before		After
9.9		6.3
6.8		6.0
6.3		6.2
5.8		6.1

So fsync performance seems unharmed by this change.
Signed-off-by: Jan Kara <jack@suse.cz>

This fixes builds where CONFIG_AUDIT is not defined and
CONFIG_SECURITY_SMACK=y.

This got introduced by the stack-usage reducation commit 48c62af6
("LSM: shrink the common_audit_data data union").
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull dmaengine fixes from Dan Williams:

1/ regression fix for Xen as it now trips over a broken assumption
   about the dma address size on 32-bit builds

2/ new quirk for netdma to ignore dma channels that cannot meet
   netdma alignment requirements

3/ fixes for two long standing issues in ioatdma (ring size overflow)
   and iop-adma (potential stack corruption)

* tag 'dmaengine-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
  netdma: adding alignment check for NETDMA ops
  ioatdma: DMA copy alignment needed to address IOAT DMA silicon errata
  ioat: ring size variables need to be 32bit to avoid overflow
  iop-adma: Corrected array overflow in RAID6 Xscale(R) test.
  ioat: fix size of 'completion' for Xen

Pull sparc fixes from David Miller:

1) Build fix for LEON, from Sam Ravnborg.

2) Make the sparc side changes that go along with the infrastructure to
   retry faults when blocking on a disk transfer.  From Kautuk Consul.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc32,leon: fix leon build
  sparc/mm/fault_32.c: Port OOM changes to do_sparc_fault
  sparc/mm/fault_64.c: Port OOM changes to do_sparc64_fault

Pull a regulator build fix from Mark Brown:
 "Fix a build warning in the anatop driver for 3.4

  This is a trivial rename to stop the build system complaining that
  we're referencing things we shouldn't be."

* tag 'regulator-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: anatop: fix 'anatop_regulator' name collision

Pull UML fixes from Richard Weinberger.

* 'for-3.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: uml_setup_stubs': warning: unused variable 'pages'
  um: Use asm-generic/switch_to.h
  um: Disintegrate asm/system.h
  um: switch cow_user.h to htobe{32,64}/betoh{32,64}
  um: several x86 hw-dependent crypto modules won't build on uml
  um: fix linker script generation

Don't call i2c_enable on resume because it causes a spurious
interrupt.
Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit f02e8a65 ("module: Sort exported symbols") sorts symbols
placing each of them in its own elf section.  This sorting and merging
into the canonical sections are done by the linker.

Unfortunately modpost to generate Module.symvers file parses vmlinux.o
(which is not linked yet) and all modules object files (which aren't
linked yet).  These aren't sanitized by the linker yet.  That breaks
modpost that can't detect license properly for modules.

This patch makes modpost aware of the new exported symbols structure.

[ This above is a slightly corrected version of the explanation of the
  problem, copied from commit 62a26356 ("modpost: Fix modpost's
  license checking V3").  That commit fixed the problem for module
  object files, but not for vmlinux.o.  This patch fixes modpost for
  vmlinux.o. ]
Signed-off-by: Frank Rowand <frank.rowand@am.sony.com>
Signed-off-by: Alessio Igor Bogani <abogani@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The task handoff notifier leaks task_struct since it never gets freed
after the callback returns NOTIFY_OK, which means it is responsible for
doing so.

It turns out the lowmemorykiller actually doesn't need this notifier at
all.  It's used to prevent unnecessary killing by waiting for a thread
to exit as a result of lowmem_shrink(), however, it's possible to do
this in the same way the kernel oom killer works by setting TIF_MEMDIE
and avoid killing if we're still waiting for it to exit.

The kernel oom killer will already automatically set TIF_MEMDIE for
threads that are attempting to allocate memory that have a fatal signal.
The thread selected by lowmem_shrink() will have such a signal after the
lowmemorykiller sends it a SIGKILL, so this won't result in an
unnecessary use of memory reserves for the thread to exit.

This has the added benefit that we don't have to rely on
CONFIG_PROFILING to prevent needlessly killing tasks.
Reported-by: Werner Landgraf <w.landgraf@ru.ru>
Cc: stable@vger.kernel.org
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Colin Cross <ccross@android.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix the following gcc complain
arch/um/kernel/skas/mmu.c: In function 'uml_setup_stubs':
arch/um/kernel/skas/mmu.c:106:16: warning: unused variable 'pages' [-Wunused-variable]
Signed-Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Signed-off-by: Richard Weinberger <richard@nod.at>

Signed-off-by: Richard Weinberger <richard@nod.at>
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
CC: dhowells@redhat.com

... rather than open-coding the 64bit versions.  endian.h has those guys.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

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

while we can't just use -U$(SUBARCH), we still need to kill idiotic define
(implicit -Di386=1), both for SUBARCH=i386 and SUBARCH=x86/CONFIG_64BIT=n
builds.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull two more small regmap fixes from Mark Brown:
 - Now we have users for it that aren't running Android it turns out
   that regcache_sync_region() is much more useful to drivers if it's
   exported for use by modules.  Who knew?
 - Make sure we don't divide by zero when doing debugfs dumps of
   rbtrees, not visible up until now because everything was providing at
   least some cache on startup.

* tag 'regmap-3.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: prevent division by zero in rbtree_show
  regmap: Export regcache_sync_region()

Pull a few KVM fixes from Avi Kivity:
 "A bunch of powerpc KVM fixes, a guest and a host RCU fix (unrelated),
  and a small build fix."

* 'kvm-updates/3.4' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Resolve RCU vs. async page fault problem
  KVM: VMX: vmx_set_cr0 expects kvm->srcu locked
  KVM: PMU: Fix integer constant is too large warning in kvm_pmu_set_msr()
  KVM: PPC: Book3S: PR: Fix preemption
  KVM: PPC: Save/Restore CR over vcpu_run
  KVM: PPC: Book3S HV: Save and restore CR in __kvmppc_vcore_entry
  KVM: PPC: Book3S HV: Fix kvm_alloc_linear in case where no linears exist
  KVM: PPC: Book3S: Compile fix for ppc32 in HIOR access code

Pull SuperH fixes from Paul Mundt.

* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
  sh: fix clock-sh7757 for the latest sh_mobile_sdhi driver
  serial: sh-sci: use serial_port_in/out vs sci_in/out.
  sh: vsyscall: Fix up .eh_frame generation.
  sh: dma: Fix up device attribute mismatch from sysdev fallout.
  sh: dwarf unwinder depends on SHcompact.
  sh: fix up fallout from system.h disintegration.

Pull security layer fixlet from James Morris.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  sysctl: fix write access to dmesg_restrict/kptr_restrict

Pull ACPI & Power Management patches from Len Brown:
 "Two fixes for cpuidle merge-window changes, plus a URL fix in
  MAINTAINERS"

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  MAINTAINERS: Update git url for ACPI
  cpuidle: Fix panic in CPU off-lining with no idle driver
  ACPI processor: Use safe_halt() rather than halt() in acpi_idle_play_dead()

Pull target fixes from Nicholas Bellinger:
 "Pull two tcm_fc fabric related fixes for -rc2:

  Note that both have been CC'ed to stable, and patch #1 is the
  important one that addresses a memory corruption bug related to FC
  exchange timeouts + command abort.

  Thanks again to MDR for tracking down this issue!"

* '3.4-rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  tcm_fc: Do not free tpg structure during wq allocation failure
  tcm_fc: Add abort flag for gracefully handling exchange timeout

Avoid freeing a registered tpg structure if an alloc_workqueue call
fails.  This fixes a bug where the failure was leaking memory associated
with se_portal_group setup during the original core_tpg_register() call.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Acked-by: Kiran Patil <Kiran.patil@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Add abort flag and use it to terminate processing when an exchange
is timed out or is reset. The abort flag is used in place of the
transport_generic_free_cmd function call in the reset and timeout
cases, because calling that function in that context would free
memory that was in use. The aborted flag allows the lifetime to
be managed in a more normal way, while truncating the processing.

This change eliminates a source of memory corruption which
manifested in a variety of ugly ways.

(nab: Drop unused struct fc_exch *ep in ft_recv_seq)
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Acked-by: Kiran Patil <Kiran.patil@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: Igor Murzov <e-mail@date.by>
Signed-off-by: Len Brown <len.brown@intel.com>

Pull arch/tile bug fixes from Chris Metcalf:
 "This includes Paul Gortmaker's change to fix the <asm/system.h>
  disintegration issues on tile, a fix to unbreak the tilepro ethernet
  driver, and a backlog of bugfix-only changes from internal Tilera
  development over the last few months.

  They have all been to LKML and on linux-next for the last few days.
  The EDAC change to MAINTAINERS is an oddity but discussion on the
  linux-edac list suggested I ask you to pull that change through my
  tree since they don't have a tree to pull edac changes from at the
  moment."

* 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: (39 commits)
  drivers/net/ethernet/tile: fix netdev_alloc_skb() bombing
  MAINTAINERS: update EDAC information
  tilepro ethernet driver: fix a few minor issues
  tile-srom.c driver: minor code cleanup
  edac: say "TILEGx" not "TILEPro" for the tilegx edac driver
  arch/tile: avoid accidentally unmasking NMI-type interrupt accidentally
  arch/tile: remove bogus performance optimization
  arch/tile: return SIGBUS for addresses that are unaligned AND invalid
  arch/tile: fix finv_buffer_remote() for tilegx
  arch/tile: use atomic exchange in arch_write_unlock()
  arch/tile: stop mentioning the "kvm" subdirectory
  arch/tile: export the page_home() function.
  arch/tile: fix pointer cast in cacheflush.c
  arch/tile: fix single-stepping over swint1 instructions on tilegx
  arch/tile: implement panic_smp_self_stop()
  arch/tile: add "nop" after "nap" to help GX idle power draw
  arch/tile: use proper memparse() for "maxmem" options
  arch/tile: fix up locking in pgtable.c slightly
  arch/tile: don't leak kernel memory when we unload modules
  arch/tile: fix bug in delay_backoff()
  ...

Merge tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull xen fixes from Konrad Rzeszutek Wilk:
 "Two fixes for regressions:
   * one is a workaround that will be removed in v3.5 with proper fix in
     the tip/x86 tree,
   * the other is to fix drivers to load on PV (a previous patch made
     them only load in PVonHVM mode).

  The rest are just minor fixes in the various drivers and some cleanup
  in the core code."

* tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/pcifront: avoid pci_frontend_enable_msix() falsely returning success
  xen/pciback: fix XEN_PCI_OP_enable_msix result
  xen/smp: Remove unnecessary call to smp_processor_id()
  xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus io-apic entries'
  xen: only check xen_platform_pci_unplug if hvm

Pull MMC fixes from Chris Ball:
 - Disable use of MSI in sdhci-pci, which caused multiple chipsets to
   stop working in 3.4-rc1.  I'll wait to turn this on again until we
   have a chipset whitelist for it.
 - Fix a libertas SDIO powered-resume regression introduced in 3.3;
   thanks to Neil Brown and Rafael Wysocki for this fix.
 - Fix module reloading on omap_hsmmc.
 - Stop trusting the spec/card's specified maximum data timeout length,
   and use three seconds instead.  Previously we used 300ms.

Also cleanups and fixes for s3c, atmel, sh_mmcif and omap_hsmmc.

* tag 'mmc-fixes-for-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (28 commits)
  mmc: use really long write timeout to deal with crappy cards
  mmc: sdhci-dove: Fix compile error by including module.h
  mmc: Prevent 1.8V switch for SD hosts that don't support UHS modes.
  Revert "mmc: sdhci-pci: Add MSI support"
  Revert "mmc: sdhci-pci: add quirks for broken MSI on O2Micro controllers"
  mmc: core: fix power class selection
  mmc: omap_hsmmc: fix module re-insertion
  mmc: omap_hsmmc: convert to module_platform_driver
  mmc: omap_hsmmc: make it behave well as a module
  mmc: omap_hsmmc: trivial cleanups
  mmc: omap_hsmmc: context save after enabling runtime pm
  mmc: omap_hsmmc: use runtime put sync in probe error patch
  mmc: sdio: Use empty system suspend/resume callbacks at the bus level
  mmc: bus: print bus speed mode of UHS-I card
  mmc: sdhci-pci: add quirks for broken MSI on O2Micro controllers
  mmc: sh_mmcif: Simplify calculation of mmc->f_min
  mmc: sh_mmcif: mmc->f_max should be half of the bus clock
  mmc: sh_mmcif: double clock speed
  mmc: block: Remove use of mmc_blk_set_blksize
  mmc: atmel-mci: add support for odd clock dividers
  ...

I have a new optimized x86 "strncpy_from_user()" that will use these
same helper functions for all the same reasons the name lookup code uses
them.  This is preparation for that.

This moves them into an architecture-specific header file.  It's
architecture-specific for two reasons:

 - some of the functions are likely to want architecture-specific
   implementations.  Even if the current code happens to be "generic" in
   the sense that it should work on any little-endian machine, it's
   likely that the "multiply by a big constant and shift" implementation
   is less than optimal for an architecture that has a guaranteed fast
   bit count instruction, for example.

 - I expect that if architectures like sparc want to start playing
   around with this, we'll need to abstract out a few more details (in
   particular the actual unaligned accesses).  So we're likely to have
   more architecture-specific stuff if non-x86 architectures start using
   this.

   (and if it turns out that non-x86 architectures don't start using
   this, then having it in an architecture-specific header is still the
   right thing to do, of course)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix a NULL pointer dereference panic in cpuidle_play_dead() during
CPU off-lining when no cpuidle driver is registered.  A cpuidle
driver may be registered at boot-time based on CPU type.  This patch
allows an off-lined CPU to enter HLT-based idle in this condition.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: Boris Ostrovsky <boris.ostrovsky@amd.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Tested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Pull networking updates from David Miller:

 1) Fix inaccuracies in network driver interface documentation, from Ben
    Hutchings.

 2) Fix handling of negative offsets in BPF JITs, from Jan Seiffert.

 3) Compile warning, locking, and refcounting fixes in netfilter's
    xt_CT, from Pablo Neira Ayuso.

 4) phonet sendmsg needs to validate user length just like any other
    datagram protocol, fix from Sasha Levin.

 5) Ipv6 multicast code uses wrong loop index, from RongQing Li.

 6) Link handling and firmware fixes in bnx2x driver from Yaniv Rosner
    and Yuval Mintz.

 7) mlx4 erroneously allocates 4 pages at a time, regardless of page
    size, fix from Thadeu Lima de Souza Cascardo.

 8) SCTP socket option wasn't extended in a backwards compatible way,
    fix from Thomas Graf.

 9) Add missing address change event emissions to bonding, from Shlomo
    Pongratz.

10) /proc/net/dev regressed because it uses a private offset to track
    where we are in the hash table, but this doesn't track the offset
    pullback that the seq_file code does resulting in some entries being
    missed in large dumps.

    Fix from Eric Dumazet.

11) do_tcp_sendpage() unloads the send queue way too fast, because it
    invokes tcp_push() when it shouldn't.  Let the natural sequence
    generated by the splice paths, and the assosciated MSG_MORE
    settings, guide the tcp_push() calls.

    Otherwise what goes out of TCP is spaghetti and doesn't batch
    effectively into GSO/TSO clusters.

    From Eric Dumazet.

12) Once we put a SKB into either the netlink receiver's queue or a
    socket error queue, it can be consumed and freed up, therefore we
    cannot touch it after queueing it like that.

    Fixes from Eric Dumazet.

13) PPP has this annoying behavior in that for every transmit call it
    immediately stops the TX queue, then calls down into the next layer
    to transmit the PPP frame.

    But if that next layer can take it immediately, it just un-stops the
    TX queue right before returning from the transmit method.

    Besides being useless work, it makes several facilities unusable, in
    particular things like the equalizers.  Well behaved devices should
    only stop the TX queue when they really are full, and in PPP's case
    when it gets backlogged to the downstream device.

    David Woodhouse therefore fixed PPP to not stop the TX queue until
    it's downstream can't take data any more.

14) IFF_UNICAST_FLT got accidently lost in some recent stmmac driver
    changes, re-add.  From Marc Kleine-Budde.

15) Fix link flaps in ixgbe, from Eric W. Multanen.

16) Descriptor writeback fixes in e1000e from Matthew Vick.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (47 commits)
  net: fix a race in sock_queue_err_skb()
  netlink: fix races after skb queueing
  doc, net: Update ndo_start_xmit return type and values
  doc, net: Remove instruction to set net_device::trans_start
  doc, net: Update netdev operation names
  doc, net: Update documentation of synchronisation for TX multiqueue
  doc, net: Remove obsolete reference to dev->poll
  ethtool: Remove exception to the requirement of holding RTNL lock
  MAINTAINERS: update for Marvell Ethernet drivers
  bonding: properly unset current_arp_slave on slave link up
  phonet: Check input from user before allocating
  tcp: tcp_sendpages() should call tcp_push() once
  ipv6: fix array index in ip6_mc_add_src()
  mlx4: allocate just enough pages instead of always 4 pages
  stmmac: re-add IFF_UNICAST_FLT for dwmac1000
  bnx2x: Clear MDC/MDIO warning message
  bnx2x: Fix BCM57711+BCM84823 link issue
  bnx2x: Clear BCM84833 LED after fan failure
  bnx2x: Fix BCM84833 PHY FW version presentation
  bnx2x: Fix link issue for BCM8727 boards.
  ...

The original XenoLinux code has always had things this way, and for
compatibility reasons (in particular with a subsequent pciback
adjustment) upstream Linux should behave the same way (allowing for two
distinct error indications to be returned by the backend).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Prior to 2.6.19 and as of 2.6.31, pci_enable_msix() can return a
positive value to indicate the number of vectors (less than the amount
requested) that can be set up for a given device. Returning this as an
operation value (secondary result) is fine, but (primary) operation
results are expected to be negative (error) or zero (success) according
to the protocol. With the frontend fixed to match the XenoLinux
behavior, the backend can now validly return zero (success) here,
passing the upper limit on the number of vectors in op->value.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

There is an extra and unnecessary call to smp_processor_id()
in cpu_bringup(). Remove it.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The above mentioned patch checks the IOAPIC and if it contains
-1, then it unmaps said IOAPIC. But under Xen we get this:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000040
IP: [<ffffffff8134e51f>] xen_irq_init+0x1f/0xb0
PGD 0
Oops: 0002 [#1] SMP
CPU 0
Modules linked in:

Pid: 1, comm: swapper/0 Not tainted 3.2.10-3.fc16.x86_64 #1 Dell Inc. Inspiron
1525                  /0U990C
RIP: e030:[<ffffffff8134e51f>]  [<ffffffff8134e51f>] xen_irq_init+0x1f/0xb0
RSP: e02b: ffff8800d42cbb70  EFLAGS: 00010202
RAX: 0000000000000000 RBX: 00000000ffffffef RCX: 0000000000000001
RDX: 0000000000000040 RSI: 00000000ffffffef RDI: 0000000000000001
RBP: ffff8800d42cbb80 R08: ffff8800d6400000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffef
R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000010
FS:  0000000000000000(0000) GS:ffff8800df5fe000(0000) knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000 CR0:000000008005003b
CR2: 0000000000000040 CR3: 0000000001a05000 CR4: 0000000000002660
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process swapper/0 (pid: 1, threadinfo ffff8800d42ca000, task ffff8800d42d0000)
Stack:
 00000000ffffffef 0000000000000010 ffff8800d42cbbe0 ffffffff8134f157
 ffffffff8100a9b2 ffffffff8182ffd1 00000000000000a0 00000000829e7384
 0000000000000002 0000000000000010 00000000ffffffff 0000000000000000
Call Trace:
 [<ffffffff8134f157>] xen_bind_pirq_gsi_to_irq+0x87/0x230
 [<ffffffff8100a9b2>] ? check_events+0x12+0x20
 [<ffffffff814bab42>] xen_register_pirq+0x82/0xe0
 [<ffffffff814bac1a>] xen_register_gsi.part.2+0x4a/0xd0
 [<ffffffff814bacc0>] acpi_register_gsi_xen+0x20/0x30
 [<ffffffff8103036f>] acpi_register_gsi+0xf/0x20
 [<ffffffff8131abdb>] acpi_pci_irq_enable+0x12e/0x202
 [<ffffffff814bc849>] pcibios_enable_device+0x39/0x40
 [<ffffffff812dc7ab>] do_pci_enable_device+0x4b/0x70
 [<ffffffff812dc878>] __pci_enable_device_flags+0xa8/0xf0
 [<ffffffff812dc8d3>] pci_enable_device+0x13/0x20

The reason we are dying is b/c the call acpi_get_override_irq() is used,
which returns the polarity and trigger for the IRQs. That function calls
mp_find_ioapics to get the 'struct ioapic' structure - which along with the
mp_irq[x] is used to figure out the default values and the polarity/trigger
overrides. Since the mp_find_ioapics now returns -1 [b/c the IOAPIC is filled
with 0xffffffff], the acpi_get_override_irq() stops trying to lookup in the
mp_irq[x] the proper INT_SRV_OVR and we can't install the SCI interrupt.

The proper fix for this is going in v3.5 and adds an x86_io_apic_ops
struct so that platforms can override it. But for v3.4 lets carry this
work-around. This patch does that by providing a slightly different variant
of the fake IOAPIC entries.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

commit b9136d207f08
  xen: initialize platform-pci even if xen_emul_unplug=never

breaks blkfront/netfront by not loading them because of
xen_platform_pci_unplug=0 and it is never set for PV guest.
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>