Pull HID fixes from Jiri Kosina:

 - kernel crash fixes for multitouch and wacom drivers, by Brent Adam
   and Dan Carpenter

 - cp2112 data packet race condition corruption fix, by Antonio Borneo

 - a few new device IDs for wacom and microsoft drivers

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: cp2112: fix to force single data-report reply
  HID: wacom: Enable pad device for older Bamboo Touch tablets
  HID: multitouch: Fix fields from pen report ID being interpreted for multitouch
  HID: microsoft: Add quirk for MS Surface Type/Touch cover
  HID: wacom: NULL dereferences on error in probe()

Pull drm fixes from Dave Airlie:
 "Aome amdgpu, one i915, one ttm and one hlcdc, nothing too scary.

  All seems fine for about this time"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/ttm: recognize ARM64 arch in ioprot handler
  drm/amdgpu/cz/dpm: properly report UVD and VCE clock levels
  drm/amdgpu/cz: implement voltage validation properly
  drm/amdgpu: add VCE harvesting instance query
  drm/amdgpu: implement VCE 3.0 harvesting support (v4)
  drm/amdgpu/dce10: Re-set VBLANK interrupt state when enabling a CRTC
  drm/amdgpu/dce11: Re-set VBLANK interrupt state when enabling a CRTC
  drm: Stop resetting connector state to unknown
  drm/i915: Use two 32bit reads for select 64bit REG_READ ioctls
  drm: atmel-hlcdc: fix vblank initial state

Pull arch/tile bugfix from Chris Metcalf:
 "This fixes a bug in freeing the initramfs memory"

* 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: use free_bootmem_late() for initrd

Pull KVM fixes from Paolo Bonzini:
 "Everything related to the new quirks and memory type features:

   - small improvements to the quirks API

   - extending one of the quirks from just AMD to Intel as well, because
     4.2 can show the same problem with problematic firmware on Intel
     too"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: rename quirk constants to KVM_X86_QUIRK_*
  KVM: vmx: obey KVM_QUIRK_CD_NW_CLEARED
  KVM: x86: introduce kvm_check_has_quirk
  KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type
  KVM: MTRR: fix memory type handling if MTRR is completely disabled

Merge tag 'drm-atmel-hlcdc/fixes-for-4.2' of https://github.com/bbrezillon/linux-at91 into drm-fixes

single hlcdc fix.

* tag 'drm-atmel-hlcdc/fixes-for-4.2' of https://github.com/bbrezillon/linux-at91:
  drm: atmel-hlcdc: fix vblank initial state

Regression fix for systemd getting confused about unknown connector state
after resume. Just stop setting the state to unknown, turned out to be a
silly idea anyway. What drivers imo really should do (and i915 still does
that) is forcing a full reprobe on resume to make sure connector changes
while suspended are caught. Most drivers seem to get this wrong. Otoh it
took us years to get fixes merged where some probe races resulted in
eating uevents, I guess userspace expectations for reliable hpd are just
really low :(

* tag 'topic/drm-fixes-2015-07-23' of git://anongit.freedesktop.org/drm-intel:
  drm: Stop resetting connector state to unknown

arb_timer kernel side fix from Chris.

* tag 'drm-intel-fixes-2015-07-23' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Use two 32bit reads for select 64bit REG_READ ioctls

Some amdgpu fixes.

* 'drm-fixes-4.2' of git://people.freedesktop.org/~agd5f/linux:
  drm/amdgpu/cz/dpm: properly report UVD and VCE clock levels
  drm/amdgpu/cz: implement voltage validation properly
  drm/amdgpu: add VCE harvesting instance query
  drm/amdgpu: implement VCE 3.0 harvesting support (v4)
  drm/amdgpu/dce10: Re-set VBLANK interrupt state when enabling a CRTC
  drm/amdgpu/dce11: Re-set VBLANK interrupt state when enabling a CRTC

Return proper pgprot for ARM64. This is required for objects like
Nouveau fences to be mapped with expected coherency.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

Pull namespace fixes from Eric Biederman:
 "While reading through the code of detach_mounts I realized the code
  was slightly off.  Testing it revealed two buggy corner cases that can
  send the code of detach_mounts into an infinite loop.

  Fixing the code to do the right thing removes the possibility of these
  user triggered infinite loops in the code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  mnt: In detach_mounts detach the appropriate unmounted mount
  mnt: Clarify and correct the disconnect logic in umount_tree

Pull virtio/vhost fixes from Michael Tsirkin:
 "Bugfixes and documentation fixes.

  Igor's patch that allows users to tweak memory table size is
  borderline, but it does fix known crashes, so I merged it"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: add max_mem_regions module parameter
  vhost: extend memory regions allocation to vmalloc
  9p/trans_virtio: reset virtio device on remove
  virtio/s390: rename drivers/s390/kvm -> drivers/s390/virtio
  MAINTAINERS: separate section for s390 virtio drivers
  virtio: define virtio_pci_cfg_cap in header.
  virtio: Fix typecast of pointer in vring_init()
  virtio scsi: fix unused variable warning
  vhost: use binary search instead of linear in find_region()
  virtio_net: document VIRTIO_NET_CTRL_GUEST_OFFLOADS

Pull iommu fixes from Joerg Roedel:
 "The fixes include:

   - a couple of fixes for the new ARM-SMMUv3 driver to fix issues found
     on the first real implementation of that hardware.

   - a patch for the Intel VT-d driver to fix a domain-id leak"

* tag 'iommu-fixes-v4.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Fix VM domain ID leak
  iommu/arm-smmu: Skip the execution of CMD_PREFETCH_CONFIG
  iommu/arm-smmu: Enlarge STRTAB_L1_SZ_SHIFT to support larger sidsize
  iommu/arm-smmu: Fix the values of ARM64_TCR_{I,O}RGN0_SHIFT
  iommu/arm-smmu: Fix LOG2SIZE setting for 2-level stream tables
  iommu/arm-smmu: Fix the index calculation of strtab

VCE, UVD DPM work similarly to SCLK DPM.  Report the current
clock levels for UVD and VCE via debugfs.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

CZ uses a different set of registers compared to previous asics
and supports separate NB and GFX planes.

Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

We were previously using free_bootmem() and just getting lucky
that nothing too bad happened.

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Cc: stable@vger.kernel.org

The handling of in detach_mounts of unmounted but connected mounts is
buggy and can lead to an infinite loop.

Correct the handling of unmounted mounts in detach_mount.  When the
mountpoint of an unmounted but connected mount is connected to a
dentry, and that dentry is deleted we need to disconnect that mount
from the parent mount and the deleted dentry.

Nothing changes for the unmounted and connected children.  They can be
safely ignored.

Cc: stable@vger.kernel.org
Fixes: ce07d891

 mnt: Honor MNT_LOCKED when detaching mounts
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Signed-off-by: Leo Liu <leo.liu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>

For boards with bad VCE blocks, only configure the working
block.

v2: use the harvest info for pipe setup
v3: fix mask check as noted by Leo
v4: add dGPU support

Reviewed-by: Christian König <christian.koenig@amd.com> (v2)
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

This doesn't seem strictly necessary with Tonga right now, but that might
change with future power management enhancements.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>

Something (ATOM BIOS?) seems to be clobbering the LB_INTERRUPT_MASK
register while the CRTC is off, which caused e.g. glxgears or
gnome-shell to hang after a modeset.

Reviewed-and-Tested-by: Alex Deucher <alexander.deucher@amd.com>
Tested-by: Sonny Jiang <sonny.jiang@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>

This continues the attempt to fix commit fb170fb4 ("iommu/vt-d:
Introduce helper functions to make code symmetric for readability").
The previous attempt in commit 71684406 ("iommu/vt-d: Detach
domain *only* from attached iommus") overlooked the fact that
dmar_domain.iommu_bmp gets cleared for VM domains when devices are
detached:

intel_iommu_detach_device
  domain_remove_one_dev_info
    domain_detach_iommu

The domain is detached from the iommu, but the iommu is still attached
to the domain, for whatever reason.  Thus when we get to domain_exit(),
we can't rely on iommu_bmp for VM domains to find the active iommus,
we must check them all.  Without that, the corresponding bit in
intel_iommu.domain_ids doesn't get cleared and repeated VM domain
creation and destruction will run out of domain IDs.  Meanwhile we
still can't call iommu_detach_domain() on arbitrary non-VM domains or
we risk clearing in-use domain IDs, as 71684406 attempted to
address.

It's tempting to modify iommu_detach_domain() to test the domain
iommu_bmp, but the call ordering from domain_remove_one_dev_info()
prevents it being able to work as fb170fb4 seems to have intended.
Caching of unused VM domains on the iommu object seems to be the root
of the problem, but this code is far too fragile for that kind of
rework to be proposed for stable, so we simply revert this chunk to
its state prior to fb170fb4.

Fixes: fb170fb4 ("iommu/vt-d: Introduce helper functions to make
                      code symmetric for readability")
Fixes: 71684406

 ("iommu/vt-d: Detach domain *only* from attached
                      iommus")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: stable@vger.kernel.org # v3.17+
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Make them clearly architecture-dependent; the capability is valid for
all architectures, but the argument is not.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

OVMF depends on WB to boot fast, because it only clears caches after
it has set up MTRRs---which is too late.

Let's do writeback if CR0.CD is set to make it happy, similar to what
SVM is already doing.

Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The logic of the disabled_quirks field usually results in a double
negation.  Wrap it in a simple function that checks the bit and
negates it.

Based on a patch from Xiao Guangrong.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

kvm_mtrr_get_guest_memory_type never returns -1 which is implied
in the current code since if @type = -1 (means no MTRR contains the
range), iter.partial_map must be true

Simplify the code to indicate this fact

Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Currently code uses default memory type if MTRR is fully disabled,
fix it by using UC instead.

Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

rmdir mntpoint will result in an infinite loop when there is
a mount locked on the mountpoint in another mount namespace.

This is because the logic to test to see if a mount should
be disconnected in umount_tree is buggy.

Move the logic to decide if a mount should remain connected to
it's mountpoint into it's own function disconnect_mount so that
clarity of expression instead of terseness of expression becomes
a virtue.

When the conditions where it is invalid to leave a mount connected
are first ruled out, the logic for deciding if a mount should
be disconnected becomes much clearer and simpler.

Fixes: e0c9c0af mnt: Update detach_mounts to leave mounts connected
Fixes: ce07d891

 mnt: Honor MNT_LOCKED when detaching mounts
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Pull networking fixes from David Miller:

 1) Don't use shared bluetooth antenna in iwlwifi driver for management
    frames, from Emmanuel Grumbach.

 2) Fix device ID check in ath9k driver, from Felix Fietkau.

 3) Off by one in xen-netback BUG checks, from Dan Carpenter.

 4) Fix IFLA_VF_PORT netlink attribute validation, from Daniel Borkmann.

 5) Fix races in setting peeked bit flag in SKBs during datagram
    receive.  If it's shared we have to clone it otherwise the value can
    easily be corrupted.  Fix from Herbert Xu.

 6) Revert fec clock handling change, causes regressions.  From Fabio
    Estevam.

 7) Fix use after free in fq_codel and sfq packet schedulers, from WANG
    Cong.

 8) ipvlan bug fixes (memory leaks, missing rcu_dereference_bh, etc.)
    from WANG Cong and Konstantin Khlebnikov.

 9) Memory leak in act_bpf packet action, from Alexei Starovoitov.

10) ARM bpf JIT bug fixes from Nicolas Schichan.

11) Fix backwards compat of ANY_LAYOUT in virtio_net driver, from
    Michael S Tsirkin.

12) Destruction of bond with different ARP header types not handled
    correctly, fix from Nikolay Aleksandrov.

13) Revert GRO receive support in ipv6 SIT tunnel driver, causes
    regressions because the GRO packets created cannot be processed
    properly on the GSO side if we forward the frame.  From Herbert Xu.

14) TCCR update race and other fixes to ravb driver from Sergei
    Shtylyov.

15) Fix SKB leaks in caif_queue_rcv_skb(), from Eric Dumazet.

16) Fix panics on packet scheduler filter replace, from Daniel Borkmann.

17) Make sure AF_PACKET sees properly IP headers in defragmented frames
    (via PACKET_FANOUT_FLAG_DEFRAG option), from Edward Hyunkoo Jee.

18) AF_NETLINK cannot hold mutex in RCU callback, fix from Florian
    Westphal.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (84 commits)
  ravb: fix ring memory allocation
  net: phy: dp83867: Fix warning check for setting the internal delay
  openvswitch: allocate nr_node_ids flow_stats instead of num_possible_nodes
  netlink: don't hold mutex in rcu callback when releasing mmapd ring
  ARM: net: fix vlan access instructions in ARM JIT.
  ARM: net: handle negative offsets in BPF JIT.
  ARM: net: fix condition for load_order > 0 when translating load instructions.
  tcp: suppress a division by zero warning
  drivers: net: cpsw: remove tx event processing in rx napi poll
  inet: frags: fix defragmented packet's IP header for af_packet
  net: mvneta: fix refilling for Rx DMA buffers
  stmmac: fix setting of driver data in stmmac_dvr_probe
  sched: cls_flow: fix panic on filter replace
  sched: cls_flower: fix panic on filter replace
  sched: cls_bpf: fix panic on filter replace
  net/mdio: fix mdio_bus_match for c45 PHY
  net: ratelimit warnings about dst entry refcount underflow or overflow
  caif: fix leaks and race in caif_queue_rcv_skb()
  qmi_wwan: add the second QMI/network interface for Sierra Wireless MC7305/MC7355
  ravb: fix race updating TCCR
  ...

Pull ARM64 fixes from Catalin Marinas:

 - arm64 build fix following the move of the thread_struct to the end of
   task_struct and the asm offsets becoming too large for the AArch64
   ISA

 - preparatory patch for moving irq_data struct members (applied now to
   reduce dependency for the next merging window)

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  ARM64/irq: Use access helper irq_data_get_affinity_mask()
  arm64: switch_to: calculate cpu context pointer using separate register

It's causing piles of issues since we've stopped forcing full detect
cycles in the sysfs interfaces with

commit c484f02d


Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Fri Mar 6 12:36:42 2015 +0000

    drm: Lighten sysfs connector 'status'

The original justification for this was that the hpd handlers could
use the unknown state as a hint to force a full detection. But current
i915 code isn't doing that any more, and no one else really uses reset
on resume. So instead just keep the old state around.

References: http://article.gmane.org/gmane.comp.freedesktop.xorg.drivers.intel/62584
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=100641
Cc: Rui Matos <tiagomatos@gmail.com>
Cc: Julien Wajsberg <felash@gmail.com>
Cc: kuddel.mail@gmx.de
Cc: Lennart Poettering <mzxreary@0pointer.de>
Cc: stable@vger.kernel.org
Acked-by: Rob Clark <robdclark@gmail.com>
Tested-by: Rui Tiago Cação Matos <tiagomatos@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

This is a preparatory patch for moving irq_data struct members.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Commit 0c8c0f03 ("x86/fpu, sched: Dynamically allocate 'struct fpu'")
moved the thread_struct to the bottom of task_struct. As a result, the
offset is now too large to be used in an immediate add on arm64 with
some kernel configs:

arch/arm64/kernel/entry.S: Assembler messages:
arch/arm64/kernel/entry.S:588: Error: immediate out of range
arch/arm64/kernel/entry.S:597: Error: immediate out of range

This patch calculates the offset using an additional register instead of
an immediate offset.

Fixes: 0c8c0f03

 ("x86/fpu, sched: Dynamically allocate 'struct fpu'")
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

The driver is written as if it can adapt to a low memory situation  allocating
less RX  skbs and TX aligned buffers than the respective RX/TX ring sizes.  In
reality  though  the driver  would malfunction in this case. Stop being overly
smart and just fail in such situation -- this is achieved by moving the memory
allocation from ravb_ring_format() to ravb_ring_init().

We leave dma_map_single() calls in place but make their failure non-fatal
by marking the corresponding RX descriptors  with zero data size which should
prevent DMA to an invalid addresses.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix warning: logical ‘or’ of collectively exhaustive tests is always true

Change the internal delay check from an 'or' condition to an 'and'
condition.

Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some architectures like POWER can have a NUMA node_possible_map that
contains sparse entries. This causes memory corruption with openvswitch
since it allocates flow_cache with a multiple of num_possible_nodes() and
assumes the node variable returned by for_each_node will index into
flow->stats[node].

Use nr_node_ids to allocate a maximal sparse array instead of
num_possible_nodes().

The crash was noticed after 3af229f2 was applied as it changed the
node_possible_map to match node_online_map on boot.
Fixes: 3af229f2



Signed-off-by: Chris J Arges <chris.j.arges@canonical.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Kirill A. Shutemov says:

This simple test-case trigers few locking asserts in kernel:

int main(int argc, char **argv)
{
        unsigned int block_size = 16 * 4096;
        struct nl_mmap_req req = {
                .nm_block_size          = block_size,
                .nm_block_nr            = 64,
                .nm_frame_size          = 16384,
                .nm_frame_nr            = 64 * block_size / 16384,
        };
        unsigned int ring_size;
	int fd;

	fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
        if (setsockopt(fd, SOL_NETLINK, NETLINK_RX_RING, &req, sizeof(req)) < 0)
                exit(1);
        if (setsockopt(fd, SOL_NETLINK, NETLINK_TX_RING, &req, sizeof(req)) < 0)
                exit(1);

	ring_size = req.nm_block_nr * req.nm_block_size;
	mmap(NULL, 2 * ring_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
	return 0;
}

+++ exited with 0 +++
BUG: sleeping function called from invalid context at /home/kas/git/public/linux-mm/kernel/locking/mutex.c:616
in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: init
3 locks held by init/1:
 #0:  (reboot_mutex){+.+...}, at: [<ffffffff81080959>] SyS_reboot+0xa9/0x220
 #1:  ((reboot_notifier_list).rwsem){.+.+..}, at: [<ffffffff8107f379>] __blocking_notifier_call_chain+0x39/0x70
 #2:  (rcu_callback){......}, at: [<ffffffff810d32e0>] rcu_do_batch.isra.49+0x160/0x10c0
Preemption disabled at:[<ffffffff8145365f>] __delay+0xf/0x20

CPU: 1 PID: 1 Comm: init Not tainted 4.1.0-00009-gbddf4c4818e0 #253
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Debian-1.8.2-1 04/01/2014
 ffff88017b3d8000 ffff88027bc03c38 ffffffff81929ceb 0000000000000102
 0000000000000000 ffff88027bc03c68 ffffffff81085a9d 0000000000000002
 ffffffff81ca2a20 0000000000000268 0000000000000000 ffff88027bc03c98
Call Trace:
 <IRQ>  [<ffffffff81929ceb>] dump_stack+0x4f/0x7b
 [<ffffffff81085a9d>] ___might_sleep+0x16d/0x270
 [<ffffffff81085bed>] __might_sleep+0x4d/0x90
 [<ffffffff8192e96f>] mutex_lock_nested+0x2f/0x430
 [<ffffffff81932fed>] ? _raw_spin_unlock_irqrestore+0x5d/0x80
 [<ffffffff81464143>] ? __this_cpu_preempt_check+0x13/0x20
 [<ffffffff8182fc3d>] netlink_set_ring+0x1ed/0x350
 [<ffffffff8182e000>] ? netlink_undo_bind+0x70/0x70
 [<ffffffff8182fe20>] netlink_sock_destruct+0x80/0x150
 [<ffffffff817e484d>] __sk_free+0x1d/0x160
 [<ffffffff817e49a9>] sk_free+0x19/0x20
[..]

Cong Wang says:

We can't hold mutex lock in a rcu callback, [..]

Thomas Graf says:

The socket should be dead at this point. It might be simpler to
add a netlink_release_ring() function which doesn't require
locking at all.

Reported-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Diagnosed-by: Cong Wang <cwang@twopensource.com>
Suggested-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Nicolas Schichan says:

====================
BPF JIT fixes for ARM

These patches are fixing bugs in the ARM JIT and should probably find
their way to a stable kernel. All 60 test_bpf tests in Linux 4.1 release
are now passing OK (was 54 out of 60 before).
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

This makes BPF_ANC | SKF_AD_VLAN_TAG and BPF_ANC | SKF_AD_VLAN_TAG_PRESENT
have the same behaviour as the in kernel VM and makes the test_bpf LD_VLAN_TAG
and LD_VLAN_TAG_PRESENT tests pass.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

Previously, the JIT would reject negative offsets known during code
generation and mishandle negative offsets provided at runtime.

Fix that by calling bpf_internal_load_pointer_neg_helper()
appropriately in the jit_get_skb_{b,h,w} slow path helpers and by forcing
the execution flow to the slow path helpers when the offset is
negative.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

To check whether the load should take the fast path or not, the code
would check that (r_skb_hlen - load_order) is greater than the offset
of the access using an "Unsigned higher or same" condition. For
halfword accesses and an skb length of 1 at offset 0, that test is
valid, as we end up comparing 0xffffffff(-1) and 0, so the fast path
is taken and the filter allows the load to wrongly succeed. A similar
issue exists for word loads at offset 0 and an skb length of less than
4.

Fix that by using the condition "Signed greater than or equal"
condition for the fast path code for load orders greater than 0.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>