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8 years agoARM: dts: realview: Fix PBX-A9 cache description
Robin Murphy [Wed, 10 Aug 2016 12:02:17 +0000 (14:02 +0200)] 
ARM: dts: realview: Fix PBX-A9 cache description

commit a20303725ec31ea0fcf498f1885b1d4245a4ee56 upstream.

Clearly QEMU is very permissive in how its PL310 model may be set up,
but the real hardware turns out to be far more particular about things
actually being correct. Fix up the DT description so that the real
thing actually boots:

- The arm,data-latency and arm,tag-latency properties need 3 cells to
  be valid, otherwise we end up retaining the default 8-cycle latencies
  which leads pretty quickly to lockup.
- The arm,dirty-latency property is only relevant to L210/L220, so get
  rid of it.
- The cache geometry override also leads to lockup and/or general
  misbehaviour. Irritatingly, the manual doesn't state the actual PL310
  configuration, but based on the boardfile code and poking registers
  from the Boot Monitor, it would seem to be 8 sets of 16KB ways.

With that, we can successfully boot to enjoy the fun of mismatched FPUs...

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoARM: dts: sunxi: Add a startup delay for fixed regulator enabled phys
Hans de Goede [Sat, 4 Jun 2016 10:58:39 +0000 (12:58 +0200)] 
ARM: dts: sunxi: Add a startup delay for fixed regulator enabled phys

commit fc51b632c7b047c25807023b76f3877aed19c770 upstream.

It seems that recent kernels have a shorter timeout when scanning for
ethernet phys causing us to hit a timeout on boards where the phy's
regulator gets enabled just before scanning, which leads to non working
ethernet.

A 10ms startup delay seems to be enough to fix it, this commit adds a
20ms startup delay just to be safe.

This has been tested on a sun4i-a10-a1000 and sun5i-a10s-wobo-i5 board,
both of which have non-working ethernet on recent kernels without this
fix.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoARM: 8561/3: dma-mapping: Don't use outer_flush_range when the L2C is coherent
Gregory CLEMENT [Fri, 15 Apr 2016 10:15:18 +0000 (11:15 +0100)] 
ARM: 8561/3: dma-mapping: Don't use outer_flush_range when the L2C is coherent

commit f12708965069410691e47d1d216ec7ad1516bfd2 upstream.

When a L2 cache controller is used in a system that provides hardware
coherency, the entire outer cache operations are useless, and can be
skipped.  Moreover, on some systems, it is harmful as it causes
deadlocks between the Marvell coherency mechanism, the Marvell PCIe
controller and the Cortex-A9.

In the current kernel implementation, the outer cache flush range
operation is triggered by the dma_alloc function.
This operation can be take place during runtime and in some
circumstances may lead to the PCIe/PL310 deadlock on Armada 375/38x
SoCs.

This patch extends the __dma_clear_buffer() function to receive a
boolean argument related to the coherency of the system. The same
things is done for the calling functions.

Reported-by: Nadav Haklai <nadavh@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoaudit: fix a double fetch in audit_log_single_execve_arg()
Paul Moore [Tue, 19 Jul 2016 21:42:57 +0000 (17:42 -0400)] 
audit: fix a double fetch in audit_log_single_execve_arg()

commit 43761473c254b45883a64441dd0bc85a42f3645c upstream.

There is a double fetch problem in audit_log_single_execve_arg()
where we first check the execve(2) argumnets for any "bad" characters
which would require hex encoding and then re-fetch the arguments for
logging in the audit record[1].  Of course this leaves a window of
opportunity for an unsavory application to munge with the data.

This patch reworks things by only fetching the argument data once[2]
into a buffer where it is scanned and logged into the audit
records(s).  In addition to fixing the double fetch, this patch
improves on the original code in a few other ways: better handling
of large arguments which require encoding, stricter record length
checking, and some performance improvements (completely unverified,
but we got rid of some strlen() calls, that's got to be a good
thing).

As part of the development of this patch, I've also created a basic
regression test for the audit-testsuite, the test can be tracked on
GitHub at the following link:

 * https://github.com/linux-audit/audit-testsuite/issues/25

[1] If you pay careful attention, there is actually a triple fetch
problem due to a strnlen_user() call at the top of the function.

[2] This is a tiny white lie, we do make a call to strnlen_user()
prior to fetching the argument data.  I don't like it, but due to the
way the audit record is structured we really have no choice unless we
copy the entire argument at once (which would require a rather
wasteful allocation).  The good news is that with this patch the
kernel no longer relies on this strnlen_user() value for anything
beyond recording it in the log, we also update it with a trustworthy
value whenever possible.

Reported-by: Pengfei Wang <wpengfeinudt@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiommu/amd: Update Alias-DTE in update_device_table()
Joerg Roedel [Tue, 26 Jul 2016 13:18:54 +0000 (15:18 +0200)] 
iommu/amd: Update Alias-DTE in update_device_table()

commit 3254de6bf74fe94c197c9f819fe62a3a3c36f073 upstream.

Not doing so might cause IO-Page-Faults when a device uses
an alias request-id and the alias-dte is left in a lower
page-mode which does not cover the address allocated from
the iova-allocator.

Fixes: 492667dacc0a ('x86/amd-iommu: Remove amd_iommu_pd_table')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiommu/amd: Init unity mappings only for dma_ops domains
Joerg Roedel [Wed, 13 Jul 2016 10:35:24 +0000 (12:35 +0200)] 
iommu/amd: Init unity mappings only for dma_ops domains

commit b548e786ce47017107765bbeb0f100202525ea83 upstream.

The default domain for a device might also be
identity-mapped. In this case the kernel would crash when
unity mappings are defined for the device. Fix that by
making sure the domain is a dma_ops domain.

Fixes: 0bb6e243d7fb ('iommu/amd: Support IOMMU_DOMAIN_DMA type allocation')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiommu/amd: Handle IOMMU_DOMAIN_DMA in ops->domain_free call-back
Joerg Roedel [Thu, 7 Jul 2016 13:57:04 +0000 (15:57 +0200)] 
iommu/amd: Handle IOMMU_DOMAIN_DMA in ops->domain_free call-back

commit cda7005ba2cbd0744fea343dd5b2aa637eba5b9e upstream.

This domain type is not yet handled in the
iommu_ops->domain_free() call-back. Fix that.

Fixes: 0bb6e243d7fb ('iommu/amd: Support IOMMU_DOMAIN_DMA type allocation')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiommu/io-pgtable-arm: Fix iova_to_phys for block entries
Will Deacon [Thu, 16 Jun 2016 17:21:19 +0000 (18:21 +0100)] 
iommu/io-pgtable-arm: Fix iova_to_phys for block entries

commit 7c6d90e2bb1a98b86d73b9e8ab4d97ed5507e37c upstream.

The implementation of iova_to_phys for the long-descriptor ARM
io-pgtable code always masks with the granule size when inserting the
low virtual address bits into the physical address determined from the
page tables. In cases where the leaf entry is found before the final
level of table (i.e. due to a block mapping), this results in rounding
down to the bottom page of the block mapping. Consequently, the physical
address range batching in the vfio_unmap_unpin is defeated and we end
up taking the long way home.

This patch fixes the problem by masking the virtual address with the
appropriate mask for the level at which the leaf descriptor is located.
The short-descriptor code already gets this right, so no change is
needed there.

Reported-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiommu/vt-d: Return error code in domain_context_mapping_one()
Wei Yang [Wed, 13 Jul 2016 13:53:21 +0000 (13:53 +0000)] 
iommu/vt-d: Return error code in domain_context_mapping_one()

commit 5c365d18a73d3979db37006eaacefc0008869c0f upstream.

In 'commit <55d940430ab9> ("iommu/vt-d: Get rid of domain->iommu_lock")',
the error handling path is changed a little, which makes the function
always return 0.

This path fixes this.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Fixes: 55d940430ab9 ('iommu/vt-d: Get rid of domain->iommu_lock')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiommu/exynos: Suppress unbinding to prevent system failure
Marek Szyprowski [Fri, 20 May 2016 13:48:21 +0000 (15:48 +0200)] 
iommu/exynos: Suppress unbinding to prevent system failure

commit b54b874fbaf5e024723e50dfb035a9916d6752b4 upstream.

Removal of IOMMU driver cannot be done reliably, so Exynos IOMMU driver
doesn't support this operation. It is essential for system operation, so
it makes sense to prevent unbinding by disabling bind/unbind sysfs
feature for SYSMMU controller driver to avoid kernel ops or trashing
memory caused by such operation.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agounicore32: mm: Add missing parameter to arch_vma_access_permitted
Guenter Roeck [Mon, 21 Mar 2016 11:20:53 +0000 (04:20 -0700)] 
unicore32: mm: Add missing parameter to arch_vma_access_permitted

commit 783011b13095430262333fd64e17666954064664 upstream.

unicore32 fails to compile with the following errors.

mm/memory.c: In function ‘__handle_mm_fault’:
mm/memory.c:3381: error:
too many arguments to function ‘arch_vma_access_permitted’
mm/gup.c: In function ‘check_vma_flags’:
mm/gup.c:456: error:
too many arguments to function ‘arch_vma_access_permitted’
mm/gup.c: In function ‘vma_permits_fault’:
mm/gup.c:640: error:
too many arguments to function ‘arch_vma_access_permitted’

Fixes: d61172b4b695b ("mm/core, x86/mm/pkeys: Differentiate instruction fetches")
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agopNFS: Fix LAYOUTGET handling of NFS4ERR_BAD_STATEID and NFS4ERR_EXPIRED
Trond Myklebust [Thu, 14 Jul 2016 19:14:02 +0000 (15:14 -0400)] 
pNFS: Fix LAYOUTGET handling of NFS4ERR_BAD_STATEID and NFS4ERR_EXPIRED

commit f7db0b283868411dc6bc8a223fd032b211d2d91f upstream.

We want to recover the open stateid if there is no layout stateid
and/or the stateid argument matches an open stateid.
Otherwise throw out the existing layout and recover from scratch, as
the layout stateid is bad.

Fixes: 183d9e7b112aa ("pnfs: rework LAYOUTGET retry handling")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agopNFS: Handle NFS4ERR_RECALLCONFLICT correctly in LAYOUTGET
Trond Myklebust [Thu, 14 Jul 2016 18:28:31 +0000 (14:28 -0400)] 
pNFS: Handle NFS4ERR_RECALLCONFLICT correctly in LAYOUTGET

commit 66b53f325876703b7ab815c482cd104609f8772c upstream.

Instead of giving up altogether and falling back to doing I/O
through the MDS, which may make the situation worse, wait for
2 lease periods for the callback to resolve itself, and then
try destroying the existing layout.

Only if this was an attempt at getting a first layout, do we
give up altogether, as the server is clearly crazy.

Fixes: 183d9e7b112aa ("pnfs: rework LAYOUTGET retry handling")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agopNFS: Fix post-layoutget error handling in pnfs_update_layout()
Trond Myklebust [Thu, 14 Jul 2016 22:34:12 +0000 (18:34 -0400)] 
pNFS: Fix post-layoutget error handling in pnfs_update_layout()

commit 56b38a1f7c781519eef09c1668a3c97ea911f86b upstream.

The non-retry error path is currently broken and ends up releasing the
reference to the layout twice. It also can end up clearing the
NFS_LAYOUT_FIRST_LAYOUTGET flag twice, causing a race.

In addition, the retry path will fail to decrement the plh_outstanding
counter.

Fixes: 183d9e7b112aa ("pnfs: rework LAYOUTGET retry handling")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agopNFS: Separate handling of NFS4ERR_LAYOUTTRYLATER and RECALLCONFLICT
Trond Myklebust [Thu, 14 Jul 2016 22:46:24 +0000 (18:46 -0400)] 
pNFS: Separate handling of NFS4ERR_LAYOUTTRYLATER and RECALLCONFLICT

commit e85d7ee42003314652ab3ae2c60e3b8cd793b65f upstream.

They are not the same error, and need to be handled differently.

Fixes: 183d9e7b112aa ("pnfs: rework LAYOUTGET retry handling")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agonfsd: don't return an unhashed lock stateid after taking mutex
Jeff Layton [Thu, 11 Aug 2016 14:37:39 +0000 (10:37 -0400)] 
nfsd: don't return an unhashed lock stateid after taking mutex

commit dd257933fa4b9fea66a1195f8a15111029810abc upstream.

nfsd4_lock will take the st_mutex before working with the stateid it
gets, but between the time when we drop the cl_lock and take the mutex,
the stateid could become unhashed (a'la FREE_STATEID). If that happens
the lock stateid returned to the client will be forgotten.

Fix this by first moving the st_mutex acquisition into
lookup_or_create_lock_state. Then, have it check to see if the lock
stateid is still hashed after taking the mutex. If it's not, then put
the stateid and try the find/create again.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agonfsd: Fix race between FREE_STATEID and LOCK
Chuck Lever [Thu, 11 Aug 2016 14:37:30 +0000 (10:37 -0400)] 
nfsd: Fix race between FREE_STATEID and LOCK

commit 42691398be08bd1fe99326911a0aa31f2c041d53 upstream.

When running LTP's nfslock01 test, the Linux client can send a LOCK
and a FREE_STATEID request at the same time. The outcome is:

Frame 324    R OPEN stateid [2,O]

Frame 115004 C LOCK lockowner_is_new stateid [2,O] offset 672000 len 64
Frame 115008 R LOCK stateid [1,L]
Frame 115012 C WRITE stateid [0,L] offset 672000 len 64
Frame 115016 R WRITE NFS4_OK
Frame 115019 C LOCKU stateid [1,L] offset 672000 len 64
Frame 115022 R LOCKU NFS4_OK
Frame 115025 C FREE_STATEID stateid [2,L]
Frame 115026 C LOCK lockowner_is_new stateid [2,O] offset 672128 len 64
Frame 115029 R FREE_STATEID NFS4_OK
Frame 115030 R LOCK stateid [3,L]
Frame 115034 C WRITE stateid [0,L] offset 672128 len 64
Frame 115038 R WRITE NFS4ERR_BAD_STATEID

In other words, the server returns stateid L in a successful LOCK
reply, but it has already released it. Subsequent uses of stateid L
fail.

To address this, protect the generation check in nfsd4_free_stateid
with the st_mutex. This should guarantee that only one of two
outcomes occurs: either LOCK returns a fresh valid stateid, or
FREE_STATEID returns NFS4ERR_LOCKS_HELD.

Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Fix-suggested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agonfs: don't create zero-length requests
Benjamin Coddington [Mon, 18 Jul 2016 14:41:57 +0000 (10:41 -0400)] 
nfs: don't create zero-length requests

commit 149a4fddd0a72d526abbeac0c8deaab03559836a upstream.

NFS doesn't expect requests with wb_bytes set to zero and may make
unexpected decisions about how to handle that request at the page IO layer.
Skip request creation if we won't have any wb_bytes in the request.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoBtrfs: fix delalloc accounting after copy_from_user faults
Chris Mason [Tue, 19 Jul 2016 12:52:36 +0000 (05:52 -0700)] 
Btrfs: fix delalloc accounting after copy_from_user faults

commit 8b8b08cbfb9021af4b54b4175fc4c51d655aac8c upstream.

Commit 56244ef151c3cd11 was almost but not quite enough to fix the
reservation math after btrfs_copy_from_user returned partial copies.

Some users are still seeing warnings in btrfs_destroy_inode, and with a
long enough test run I'm able to trigger them as well.

This patch fixes the accounting math again, bringing it much closer to
the way it was before the sectorsize conversion Chandan did.  The
problem is accounting for the offset into the page/sector when we do a
partial copy.  This one just uses the dirty_sectors variable which
should already be updated properly.

Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agopowerpc/tm: Fix stack pointer corruption in __tm_recheckpoint()
Michael Neuling [Wed, 6 Jul 2016 04:58:06 +0000 (14:58 +1000)] 
powerpc/tm: Fix stack pointer corruption in __tm_recheckpoint()

commit 6bcb80143e792becfd2b9cc6a339ce523e4e2219 upstream.

At the start of __tm_recheckpoint() we save the kernel stack pointer
(r1) in SPRG SCRATCH0 (SPRG2) so that we can restore it after the
trecheckpoint.

Unfortunately, the same SPRG is used in the SLB miss handler.  If an
SLB miss is taken between the save and restore of r1 to the SPRG, the
SPRG is changed and hence r1 is also corrupted.  We can end up with
the following crash when we start using r1 again after the restore
from the SPRG:

  Oops: Bad kernel stack pointer, sig: 6 [#1]
  SMP NR_CPUS=2048 NUMA pSeries
  CPU: 658 PID: 143777 Comm: htm_demo Tainted: G            EL   X 4.4.13-0-default #1
  task: c0000b56993a7810 ti: c00000000cfec000 task.ti: c0000b56993bc000
  NIP: c00000000004f188 LR: 00000000100040b8 CTR: 0000000010002570
  REGS: c00000000cfefd40 TRAP: 0300   Tainted: G            EL   X  (4.4.13-0-default)
  MSR: 8000000300001033 <SF,ME,IR,DR,RI,LE>  CR: 02000424  XER: 20000000
  CFAR: c000000000008468 DAR: 00003ffd84e66880 DSISR: 40000000 SOFTE: 0
  PACATMSCRATCH: 00003ffbc865e680
  GPR00: fffffffcfabc4268 00003ffd84e667a0 00000000100d8c38 000000030544bb80
  GPR04: 0000000000000002 00000000100cf200 0000000000000449 00000000100cf100
  GPR08: 000000000000c350 0000000000002569 0000000000002569 00000000100d6c30
  GPR12: 00000000100d6c28 c00000000e6a6b00 00003ffd84660000 0000000000000000
  GPR16: 0000000000000003 0000000000000449 0000000010002570 0000010009684f20
  GPR20: 0000000000800000 00003ffd84e5f110 00003ffd84e5f7a0 00000000100d0f40
  GPR24: 0000000000000000 0000000000000000 0000000000000000 00003ffff0673f50
  GPR28: 00003ffd84e5e960 00000000003d0f00 00003ffd84e667a0 00003ffd84e5e680
  NIP [c00000000004f188] restore_gprs+0x110/0x17c
  LR [00000000100040b8] 0x100040b8
  Call Trace:
  Instruction dump:
  f8a1fff0 e8e700a8 38a00000 7ca10164 e8a1fff8 e821fff0 7c0007dd 7c421378
  7db142a6 7c3242a6 38800002 7c810164 <e9c100e0e9e100e8 ea0100f0 ea2100f8

We hit this on large memory machines (> 2TB) but it can also be hit on
smaller machines when 1TB segments are disabled.

To hit this, you also need to be virtualised to ensure SLBs are
periodically removed by the hypervisor.

This patches moves the saving of r1 to the SPRG to the region where we
are guaranteed not to take any further SLB misses.

Fixes: 98ae22e15b43 ("powerpc: Add helper functions for transactional memory context switching")
Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoMIPS: KVM: Propagate kseg0/mapped tlb fault errors
James Hogan [Thu, 11 Aug 2016 10:58:15 +0000 (11:58 +0100)] 
MIPS: KVM: Propagate kseg0/mapped tlb fault errors

commit 9b731bcfdec4c159ad2e4312e25d69221709b96a upstream.

Propagate errors from kvm_mips_handle_kseg0_tlb_fault() and
kvm_mips_handle_mapped_seg_tlb_fault(), usually triggering an internal
error since they normally indicate the guest accessed bad physical
memory or the commpage in an unexpected way.

Fixes: 858dd5d45733 ("KVM/MIPS32: MMU/TLB operations for the Guest.")
Fixes: e685c689f3a8 ("KVM/MIPS32: Privileged instruction/target branch emulation.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.10.x-
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[james.hogan@imgtec.com: Backport to v4.7]
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoMIPS: KVM: Fix gfn range check in kseg0 tlb faults
James Hogan [Thu, 11 Aug 2016 10:58:14 +0000 (11:58 +0100)] 
MIPS: KVM: Fix gfn range check in kseg0 tlb faults

commit 0741f52d1b980dbeb290afe67d88fc2928edd8ab upstream.

Two consecutive gfns are loaded into host TLB, so ensure the range check
isn't off by one if guest_pmap_npages is odd.

Fixes: 858dd5d45733 ("KVM/MIPS32: MMU/TLB operations for the Guest.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.10.x-
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[james.hogan@imgtec.com: Backport to v4.7]
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoMIPS: KVM: Add missing gfn range check
James Hogan [Thu, 11 Aug 2016 10:58:13 +0000 (11:58 +0100)] 
MIPS: KVM: Add missing gfn range check

commit 8985d50382359e5bf118fdbefc859d0dbf6cebc7 upstream.

kvm_mips_handle_mapped_seg_tlb_fault() calculates the guest frame number
based on the guest TLB EntryLo values, however it is not range checked
to ensure it lies within the guest_pmap. If the physical memory the
guest refers to is out of range then dump the guest TLB and emit an
internal error.

Fixes: 858dd5d45733 ("KVM/MIPS32: MMU/TLB operations for the Guest.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.10.x-
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[james.hogan@imgtec.com: Backport to v4.7]
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoMIPS: KVM: Fix mapped fault broken commpage handling
James Hogan [Thu, 11 Aug 2016 10:58:12 +0000 (11:58 +0100)] 
MIPS: KVM: Fix mapped fault broken commpage handling

commit c604cffa93478f8888bec62b23d6073dad03d43a upstream.

kvm_mips_handle_mapped_seg_tlb_fault() appears to map the guest page at
virtual address 0 to PFN 0 if the guest has created its own mapping
there. The intention is unclear, but it may have been an attempt to
protect the zero page from being mapped to anything but the comm page in
code paths you wouldn't expect from genuine commpage accesses (guest
kernel mode cache instructions on that address, hitting trapping
instructions when executing from that address with a coincidental TLB
eviction during the KVM handling, and guest user mode accesses to that
address).

Fix this to check for mappings exactly at KVM_GUEST_COMMPAGE_ADDR (it
may not be at address 0 since commit 42aa12e74e91 ("MIPS: KVM: Move
commpage so 0x0 is unmapped")), and set the corresponding EntryLo to be
interpreted as 0 (invalid).

Fixes: 858dd5d45733 ("KVM/MIPS32: MMU/TLB operations for the Guest.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.10.x-
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[james.hogan@imgtec.com: Backport to v4.7]
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agocachefiles: Fix race between inactivating and culling a cache object
David Howells [Wed, 3 Aug 2016 16:57:39 +0000 (17:57 +0100)] 
cachefiles: Fix race between inactivating and culling a cache object

commit db20a8925bc420eed033c5d91ff6afa74465e521 upstream.

There's a race between cachefiles_mark_object_inactive() and
cachefiles_cull():

 (1) cachefiles_cull() can't delete a backing file until the cache object
     is marked inactive, but as soon as that's the case it's fair game.

 (2) cachefiles_mark_object_inactive() marks the object as being inactive
     and *only then* reads the i_blocks on the backing inode - but
     cachefiles_cull() might've managed to delete it by this point.

Fix this by making sure cachefiles_mark_object_inactive() gets any data it
needs from the backing inode before deactivating the object.

Without this, the following oops may occur:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
IP: [<ffffffffa06c5cc1>] cachefiles_mark_object_inactive+0x61/0xb0 [cachefiles]
...
CPU: 11 PID: 527 Comm: kworker/u64:4 Tainted: G          I    ------------   3.10.0-470.el7.x86_64 #1
Hardware name: Hewlett-Packard HP Z600 Workstation/0B54h, BIOS 786G4 v03.19 03/11/2011
Workqueue: fscache_object fscache_object_work_func [fscache]
task: ffff880035edaf10 ti: ffff8800b77c0000 task.ti: ffff8800b77c0000
RIP: 0010:[<ffffffffa06c5cc1>] cachefiles_mark_object_inactive+0x61/0xb0 [cachefiles]
RSP: 0018:ffff8800b77c3d70  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8800bf6cc400 RCX: 0000000000000034
RDX: 0000000000000000 RSI: ffff880090ffc710 RDI: ffff8800bf761ef8
RBP: ffff8800b77c3d88 R08: 2000000000000000 R09: 0090ffc710000000
R10: ff51005d2ff1c400 R11: 0000000000000000 R12: ffff880090ffc600
R13: ffff8800bf6cc520 R14: ffff8800bf6cc400 R15: ffff8800bf6cc498
FS:  0000000000000000(0000) GS:ffff8800bb8c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000098 CR3: 00000000019ba000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
 ffff880090ffc600 ffff8800bf6cc400 ffff8800867df140 ffff8800b77c3db0
 ffffffffa06c48cb ffff880090ffc600 ffff880090ffc180 ffff880090ffc658
 ffff8800b77c3df0 ffffffffa085d846 ffff8800a96b8150 ffff880090ffc600
Call Trace:
 [<ffffffffa06c48cb>] cachefiles_drop_object+0x6b/0xf0 [cachefiles]
 [<ffffffffa085d846>] fscache_drop_object+0xd6/0x1e0 [fscache]
 [<ffffffffa085d615>] fscache_object_work_func+0xa5/0x200 [fscache]
 [<ffffffff810a605b>] process_one_work+0x17b/0x470
 [<ffffffff810a6e96>] worker_thread+0x126/0x410
 [<ffffffff810a6d70>] ? rescuer_thread+0x460/0x460
 [<ffffffff810ae64f>] kthread+0xcf/0xe0
 [<ffffffff810ae580>] ? kthread_create_on_node+0x140/0x140
 [<ffffffff81695418>] ret_from_fork+0x58/0x90
 [<ffffffff810ae580>] ? kthread_create_on_node+0x140/0x140

The oopsing code shows:

callq  0xffffffff810af6a0 <wake_up_bit>
mov    0xf8(%r12),%rax
mov    0x30(%rax),%rax
mov    0x98(%rax),%rax   <---- oops here
lock add %rax,0x130(%rbx)

where this is:

d_backing_inode(object->dentry)->i_blocks

Fixes: a5b3a80b899bda0f456f1246c4c5a1191ea01519 (CacheFiles: Provide read-and-reset release counters for cachefilesd)
Reported-by: Jianhong Yin <jiyin@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agorandom: print a warning for the first ten uninitialized random users
Theodore Ts'o [Mon, 13 Jun 2016 14:10:51 +0000 (10:10 -0400)] 
random: print a warning for the first ten uninitialized random users

commit 9b4d008787f864f17d008c9c15bbe8a0f7e2fc24 upstream.

Since systemd is consistently using /dev/urandom before it is
initialized, we can't see the other potentially dangerous users of
/dev/urandom immediately after boot.  So print the first ten such
complaints instead.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agorandom: initialize the non-blocking pool via add_hwgenerator_randomness()
Theodore Ts'o [Sun, 12 Jun 2016 22:11:51 +0000 (18:11 -0400)] 
random: initialize the non-blocking pool via add_hwgenerator_randomness()

commit 3371f3da08cff4b75c1f2dce742d460539d6566d upstream.

If we have a hardware RNG and are using the in-kernel rngd, we should
use this to initialize the non-blocking pool so that getrandom(2)
doesn't block unnecessarily.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agorandom: properly align get_random_int_hash
Eric Biggers [Thu, 5 May 2016 01:08:39 +0000 (21:08 -0400)] 
random: properly align get_random_int_hash

commit b1132deac01c2332d234fa821a70022796b79182 upstream.

get_random_long() reads from the get_random_int_hash array using an
unsigned long pointer.  For this code to be guaranteed correct on all
architectures, the array must be aligned to an unsigned long boundary.

Signed-off-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agorandom: add interrupt callback to VMBus IRQ handler
Stephan Mueller [Mon, 2 May 2016 06:14:34 +0000 (02:14 -0400)] 
random: add interrupt callback to VMBus IRQ handler

commit 4b44f2d18a330565227a7348844493c59366171e upstream.

The Hyper-V Linux Integration Services use the VMBus implementation for
communication with the Hypervisor. VMBus registers its own interrupt
handler that completely bypasses the common Linux interrupt handling.
This implies that the interrupt entropy collector is not triggered.

This patch adds the interrupt entropy collection callback into the VMBus
interrupt handler function.

Signed-off-by: Stephan Mueller <stephan.mueller@atsec.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoCIFS: Fix a possible invalid memory access in smb2_query_symlink()
Pavel Shilovsky [Sun, 24 Jul 2016 07:37:38 +0000 (10:37 +0300)] 
CIFS: Fix a possible invalid memory access in smb2_query_symlink()

commit 7893242e2465aea6f2cbc2639da8fa5ce96e8cc2 upstream.

During following a symbolic link we received err_buf from SMB2_open().
While the validity of SMB2 error response is checked previously
in smb2_check_message() a symbolic link payload is not checked at all.
Fix it by adding such checks.

Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agocifs: fix crash due to race in hmac(md5) handling
Rabin Vincent [Tue, 19 Jul 2016 07:26:21 +0000 (09:26 +0200)] 
cifs: fix crash due to race in hmac(md5) handling

commit bd975d1eead2558b76e1079e861eacf1f678b73b upstream.

The secmech hmac(md5) structures are present in the TCP_Server_Info
struct and can be shared among multiple CIFS sessions.  However, the
server mutex is not currently held when these structures are allocated
and used, which can lead to a kernel crashes, as in the scenario below:

mount.cifs(8) #1 mount.cifs(8) #2

Is secmech.sdeschmaccmd5 allocated?
// false

Is secmech.sdeschmaccmd5 allocated?
// false

secmech.hmacmd = crypto_alloc_shash..
secmech.sdeschmaccmd5 = kzalloc..
sdeschmaccmd5->shash.tfm = &secmec.hmacmd;

secmech.sdeschmaccmd5 = kzalloc
// sdeschmaccmd5->shash.tfm
// not yet assigned

crypto_shash_update()
 deref NULL sdeschmaccmd5->shash.tfm

 Unable to handle kernel paging request at virtual address 00000030
 epc   : 8027ba34 crypto_shash_update+0x38/0x158
 ra    : 8020f2e8 setup_ntlmv2_rsp+0x4bc/0xa84
 Call Trace:
  crypto_shash_update+0x38/0x158
  setup_ntlmv2_rsp+0x4bc/0xa84
  build_ntlmssp_auth_blob+0xbc/0x34c
  sess_auth_rawntlmssp_authenticate+0xac/0x248
  CIFS_SessSetup+0xf0/0x178
  cifs_setup_session+0x4c/0x84
  cifs_get_smb_ses+0x2c8/0x314
  cifs_mount+0x38c/0x76c
  cifs_do_mount+0x98/0x440
  mount_fs+0x20/0xc0
  vfs_kern_mount+0x58/0x138
  do_mount+0x1e8/0xccc
  SyS_mount+0x88/0xd4
  syscall_common+0x30/0x54

Fix this by locking the srv_mutex around the code which uses these
hmac(md5) structures.  All the other secmech algos already have similar
locking.

Fixes: 95dc8dd14e2e84cc ("Limit allocation of crypto mechanisms to dialect which requires")
Signed-off-by: Rabin Vincent <rabinv@axis.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agocifs: unbreak TCP session reuse
Rabin Vincent [Tue, 19 Jul 2016 07:25:45 +0000 (09:25 +0200)] 
cifs: unbreak TCP session reuse

commit b782fcc1cbeb7e336c0ed1f00004b2208f48ffe0 upstream.

adfeb3e0 ("cifs: Make echo interval tunable") added a comparison of
vol->echo_interval to server->echo_interval as a criterium to
match_server(), but:

 (1) A default value is set for server->echo_interval but not for
 vol->echo_interval, meaning these can never match if the echo_interval
 option is not specified.

 (2) vol->echo_interval is in seconds but server->echo_interval is in
 jiffies, meaning these can never match even if the echo_interval option
 is specified.

This broke TCP session reuse since match_server() can never return 1.
Fix it.

Fixes: adfeb3e0 ("cifs: Make echo interval tunable")
Signed-off-by: Rabin Vincent <rabinv@axis.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agocifs: Check for existing directory when opening file with O_CREAT
Sachin Prabhu [Thu, 7 Jul 2016 20:28:27 +0000 (21:28 +0100)] 
cifs: Check for existing directory when opening file with O_CREAT

commit 8d9535b6efd86e6c07da59f97e68f44efb7fe080 upstream.

When opening a file with O_CREAT flag, check to see if the file opened
is an existing directory.

This prevents the directory from being opened which subsequently causes
a crash when the close function for directories cifs_closedir() is called
which frees up the file->private_data memory while the file is still
listed on the open file list for the tcon.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agofs/cifs: make share unaccessible at root level mountable
Aurelien Aptel [Wed, 25 May 2016 17:59:09 +0000 (19:59 +0200)] 
fs/cifs: make share unaccessible at root level mountable

commit a6b5058fafdf508904bbf16c29b24042cef3c496 upstream.

if, when mounting //HOST/share/sub/dir/foo we can query /sub/dir/foo but
not any of the path components above:

- store the /sub/dir/foo prefix in the cifs super_block info
- in the superblock, set root dentry to the subpath dentry (instead of
  the share root)
- set a flag in the superblock to remember it
- use prefixpath when building path from a dentry

fixes bso#8950

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agojbd2: make journal y2038 safe
Arnd Bergmann [Thu, 30 Jun 2016 15:49:01 +0000 (11:49 -0400)] 
jbd2: make journal y2038 safe

commit abcfb5d979892fc8b12574551fc907c05fe1b11b upstream.

The jbd2 journal stores the commit time in 64-bit seconds and 32-bit
nanoseconds, which avoids an overflow in 2038, but it gets the numbers
from current_kernel_time(), which uses 'long' seconds on 32-bit
architectures.

This simply changes the code to call current_kernel_time64() so
we use 64-bit seconds consistently.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoARC: dma: fix address translation in arc_dma_free
Vladimir Kondratiev [Sun, 3 Jul 2016 07:07:48 +0000 (10:07 +0300)] 
ARC: dma: fix address translation in arc_dma_free

commit b4dff2874006e54b60ce4f4dbcfec9ab81c6aff4 upstream.

page should be calculated using physical address.
If platform uses non-trivial dma-to-phys memory translation,
dma_handle should be converted to physicval address before
calculation of page.

Failing to do so results in struct page * pointing to
wrong or non-existent memory.

Fixes: f2e3d55397ff ("ARC: dma: reintroduce platform specific dma<->phys")
Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@intel.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoARC: mm: don't loose PTE_SPECIAL in pte_modify()
Vineet Gupta [Thu, 28 Jul 2016 18:35:50 +0000 (11:35 -0700)] 
ARC: mm: don't loose PTE_SPECIAL in pte_modify()

commit 3925a16ae980c79d1a8fd182d7f9487da1edd4dc upstream.

LTP madvise05 was generating mm splat

| [ARCLinux]# /sd/ltp/testcases/bin/madvise05
| BUG: Bad page map in process madvise05  pte:80e08211 pmd:9f7d4000
| page:9fdcfc90 count:1 mapcount:-1 mapping:  (null) index:0x0 flags: 0x404(referenced|reserved)
| page dumped because: bad pte
| addr:200b8000 vm_flags:00000070 anon_vma:  (null) mapping:  (null) index:1005c
| file:  (null) fault:  (null) mmap:  (null) readpage:  (null)
| CPU: 2 PID: 6707 Comm: madvise05

And for newer kernels, the system was rendered unusable afterwards.

The problem was mprotect->pte_modify() clearing PTE_SPECIAL (which is
set to identify the special zero page wired to the pte).
When pte was finally unmapped, special casing for zero page was not
done, and instead it was treated as a "normal" page, tripping on the
map counts etc.

This fixes ARC STAR 9001053308

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoremoteproc: Fix potential race condition in rproc_add
Dave Gerlach [Wed, 25 May 2016 20:41:28 +0000 (15:41 -0500)] 
remoteproc: Fix potential race condition in rproc_add

commit d2e12e66a939c54ed84e5f1b6947f0c45f6c56eb upstream.

rproc_add adds the newly created remoteproc to a list for use by
rproc_get_by_phandle and then does some additional processing to finish
adding the remoteproc. This leaves a small window of time in which the
rproc is available in the list but not yet fully initialized, so if
another driver comes along and gets a handle to the rproc, it will be
invalid. Rearrange the code in rproc_add to make sure the rproc is added
to the list only after it has been successfuly initialized.

Fixes: fec47d863587 ("remoteproc: introduce rproc_get_by_phandle API")
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoovl: disallow overlayfs as upperdir
Miklos Szeredi [Fri, 29 Jul 2016 10:05:24 +0000 (12:05 +0200)] 
ovl: disallow overlayfs as upperdir

commit 76bc8e2843b66f8205026365966b49ec6da39ae7 upstream.

This does not work and does not make sense.  So instead of fixing it
(probably not hard) just disallow.

Reported-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoHID: uhid: fix timeout when probe races with IO
Roderick Colenbrander [Wed, 18 May 2016 20:11:09 +0000 (13:11 -0700)] 
HID: uhid: fix timeout when probe races with IO

commit 67f8ecc550b5bda03335f845dc869b8501d25fd0 upstream.

Many devices use userspace bluetooth stacks like BlueZ or Bluedroid in combination
with uhid. If any of these stacks is used with a HID device for which the driver
performs a HID request as part .probe (or technically another HID operation),
this results in a deadlock situation. The deadlock results in a 5 second timeout
for I/O operations in HID drivers, so isn't fatal, but none of the I/O operations
have a chance of succeeding.

The root cause for the problem is that uhid only allows for one request to be
processed at a time per uhid instance and locks out other operations. This means
that if a user space is creating a new HID device through 'UHID_CREATE', which
ultimately triggers '.probe' through the HID layer. Then any HID request e.g. a
read for calibration data would trigger a HID operation on uhid again, but it
won't go out to userspace, because it is still stuck in UHID_CREATE.
In addition bluetooth stacks are typically single threaded, so they wouldn't be
able to handle any requests while waiting on uhid.

Lucikly the UHID spec is somewhat flexible and allows for fixing the issue,
without breaking user space. The idea which the patch implements as discussed
with David Herrmann is to decouple adding of a hid device (which triggers .probe)
from UHID_CREATE. The work will kick off roughly once UHID_CREATE completed (or
else will wait a tiny bit of time in .probe for a lock). A HID driver has to call
HID to call 'hid_hw_start()' as part of .probe once it is ready for I/O, which
triggers UHID_START to user space. Any HID operations should function now within
.probe and won't deadlock because userspace is stuck on UHID_CREATE.

We verified this patch on Bluedroid with Android 6.0 and on desktop Linux with
BlueZ stacks. Prior to the patch they had the deadlock issue.

[jkosina@suse.cz: reword subject]
Signed-off-by: Roderick Colenbrander <roderick.colenbrander@sony.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agomegaraid_sas: Do not fire MR_DCMD_PD_LIST_QUERY to controllers which do not support it
Sumit Saxena [Fri, 8 Jul 2016 10:30:16 +0000 (03:30 -0700)] 
megaraid_sas: Do not fire MR_DCMD_PD_LIST_QUERY to controllers which do not support it

commit d9083160c2f6ee456ea867ea2279c1fc6124e56f upstream.

There was an issue reported by Lucz Geza on Dell Perc 6i. As per issue
reported, megaraid_sas driver goes into an infinite error reporting loop
as soon as there is a change in the status of one of the
arrays (degrade, resync online etc ).  Below are the error logs reported
continuously-

Jun 25 08:49:30 ns8 kernel: [  757.757017] megaraid_sas 0000:02:00.0: DCMD failed/not supported by firmware: megasas_get_pd_list 4115
Jun 25 08:49:30 ns8 kernel: [  757.778017] megaraid_sas 0000:02:00.0: DCMD failed/not supported by firmware: megasas_get_pd_list 4115
Jun 25 08:49:30 ns8 kernel: [  757.799017] megaraid_sas 0000:02:00.0: DCMD failed/not supported by firmware: megasas_get_pd_list 4115
Jun 25 08:49:30 ns8 kernel: [  757.820018] megaraid_sas 0000:02:00.0: DCMD failed/not supported by firmware: megasas_get_pd_list 4115
Jun 25 08:49:30 ns8 kernel: [  757.841018] megaraid_sas 0000:02:00.0: DCMD failed/not supported by firmware: megasas_get_pd_list 4115

This issue is very much specific to controllers which do not support
DCMD- MR_DCMD_PD_LIST_QUERY.  In case of any hotplugging/rescanning of
drives, AEN thread will be scheduled by driver and fire DCMD-
MR_DCMD_PD_LIST_QUERY and if this DCMD is failed then driver will fail
this event processing and will not go ahead for further events. This
will cause infinite loop of same event getting retried infinitely and
causing above mentioned logs.

Fix for this problem is: not to fire DCMD MR_DCMD_PD_LIST_QUERY for
controllers which do not support it and send DCMD SUCCESS status to AEN
function so that it can go ahead with other event processing.

Reported-by: Lucz Geza <geza@lucz.com>
Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoEDAC: Correct channel count limit
Borislav Petkov [Fri, 10 Jun 2016 08:28:38 +0000 (10:28 +0200)] 
EDAC: Correct channel count limit

commit bba142957e04c400440d2df83c1b3b2dfc42e220 upstream.

c44696fff04f ("EDAC: Remove arbitrary limit on number of channels")
lifted the arbitrary limit on memory controller channels in EDAC.
However, the dynamic channel attributes dynamic_csrow_dimm_attr and
dynamic_csrow_ce_count_attr remained 6.

This wasn't a problem except channels 6 and 7 weren't visible in sysfs
on machines with more than 6 channels after the conversion to static
attr groups with

  2c1946b6d629 ("EDAC: Use static attribute groups for managing sysfs entries")

 [ without that, we're exploding in edac_create_sysfs_mci_device()
   because we're dereferencing out of the bounds of the
   dynamic_csrow_dimm_attr array. ]

Add attributes for channels 6 and 7 along with a guard for the
future, should more channels be required and/or to sanity check for
misconfigured machines.

We still need to check against the number of channels present on the MC
first, as Thor reported.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reported-by: Hironobu Ishii <ishii.hironobu@jp.fujitsu.com>
Tested-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoBluetooth: Fix l2cap_sock_setsockopt() with optname BT_RCVMTU
Amadeusz Sławiński [Thu, 14 Jul 2016 08:50:23 +0000 (10:50 +0200)] 
Bluetooth: Fix l2cap_sock_setsockopt() with optname BT_RCVMTU

commit 23bc6ab0a0912146fd674a0becc758c3162baabc upstream.

When we retrieve imtu value from userspace we should use 16 bit pointer
cast instead of 32 as it's defined that way in headers. Fixes setsockopt
calls on big-endian platforms.

Signed-off-by: Amadeusz Sławiński <amadeusz.slawinski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoBluetooth: Add support of 13d3:3490 AR3012 device
Dmitry Tunin [Mon, 11 Jul 2016 22:35:18 +0000 (01:35 +0300)] 
Bluetooth: Add support of 13d3:3490 AR3012 device

commit 12d868964f7352e8b18e755488f7265a93431de1 upstream.

T: Bus=01 Lev=01 Prnt=01 Port=07 Cnt=05 Dev#= 5 Spd=12 MxCh= 0
D: Ver= 1.10 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=13d3 ProdID=3490 Rev=00.01
C: #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=100mA
I: If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
I: If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb

BugLink: https://bugs.launchpad.net/bugs/1600623
Signed-off-by: Dmitry Tunin <hanipouspilot@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agobrcmfmac: restore stopping netdev queue when bus clogs up
Arend Van Spriel [Fri, 15 Jul 2016 10:16:12 +0000 (12:16 +0200)] 
brcmfmac: restore stopping netdev queue when bus clogs up

commit 82bc9ab6a8f577d2174a736c33f3d4ecf7d9ef47 upstream.

When the host-interface bus has hard time handling transmit packets
it informs higher layer about this and it would stop the netdev
queue when needed. However, since commit 9cd18359d31e ("brcmfmac:
Make FWS queueing configurable.") this was broken. With this patch
the behaviour is restored.

Fixes: 9cd18359d31e ("brcmfmac: Make FWS queueing configurable.")
Tested-by: Per Förlin <per.forlin@gmail.com>
Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Franky Lin <franky.lin@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agospi: pxa2xx: Clear all RFT bits in reset_sccr1() on Intel Quark
Andy Shevchenko [Wed, 6 Jul 2016 09:08:11 +0000 (12:08 +0300)] 
spi: pxa2xx: Clear all RFT bits in reset_sccr1() on Intel Quark

commit 152bc19e2fc2b7fce7ffbc2a9cea94b147223702 upstream.

It seems the commit e5262d0568dc ("spi: spi-pxa2xx: SPI support for Intel Quark
X1000") misses one place to be adapted for Intel Quark, i.e. in reset_sccr1().

Clear all RFT bits when call reset_sccr1() on Intel Quark.

Fixes: e5262d0568dc ("spi: spi-pxa2xx: SPI support for Intel Quark X1000")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoi2c: efm32: fix a failure path in efm32_i2c_probe()
Alexey Khoroshilov [Fri, 15 Jul 2016 23:36:38 +0000 (02:36 +0300)] 
i2c: efm32: fix a failure path in efm32_i2c_probe()

commit 7dd91d52a813f99a95d20f539b777e9e6198b931 upstream.

There is the only failure path in efm32_i2c_probe(),
where clk_disable_unprepare() is missed.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: 1b5b23718b84 ("i2c: efm32: new bus driver")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agobcma: add PCI ID for Foxconn's BCM43142 device
Rafał Miłecki [Mon, 11 Jul 2016 21:01:36 +0000 (23:01 +0200)] 
bcma: add PCI ID for Foxconn's BCM43142 device

commit 1bea0512c3394965de28a152149b90afd686fae5 upstream.

After discovering there are 2 very different 14e4:4365 PCI devices we
made ID tables less generic. Back then we believed there are only 2 such
devices:
1) 14e4:4365 1028:0016 with SoftMAC BCM43142 chipset
2) 14e4:4365 14e4:4365 with FullMAC BCM4366 chipset

>From the recent report it appears there is also 14e4:4365 105b:e092
which should be claimed by bcma. Add back support for it.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=121881
Fixes: 515b399c9a20 ("bcma: claim only 14e4:4365 PCI Dell card with SoftMAC BCM43142")
Reported-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Tested-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiwlwifi: add new 8265
Oren Givon [Mon, 23 May 2016 06:58:17 +0000 (09:58 +0300)] 
iwlwifi: add new 8265

commit f24bbae565d279cd90c904fe55b539a45631705e upstream.

Add 6 new 8265 series PCI IDs:
  - (0x24FD, 0x1130)
  - (0x24FD, 0x0130)
  - (0x24FD, 0x0910)
  - (0x24FD, 0x0930)
  - (0x24FD, 0x0950)
  - (0x24FD, 0x0850)

Signed-off-by: Oren Givon <oren.givon@intel.com>
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiwlwifi: add new 8260 PCI IDs
Oren Givon [Mon, 23 May 2016 06:58:17 +0000 (09:58 +0300)] 
iwlwifi: add new 8260 PCI IDs

commit 4b79deece5d45396422d469afa11f9d69ccb3d8b upstream.

Add 3 new 8260 series PCI IDs:
  - (0x24F3, 0x10B0)
  - (0x24F3, 0xD0B0)
  - (0x24F3, 0xB0B0)

Signed-off-by: Oren Givon <oren.givon@intel.com>
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiwlwifi: pcie: fix a race in firmware loading flow
Emmanuel Grumbach [Mon, 13 Jun 2016 05:28:26 +0000 (08:28 +0300)] 
iwlwifi: pcie: fix a race in firmware loading flow

commit f16c3ebfa64fdf0e2dc88e6baa72da95ab70ffd7 upstream.

Upon firmware load interrupt (FH_TX), the ISR re-enables the
firmware load interrupt only to avoid races with other
flows as described in the commit below. When the firmware
is completely loaded, the thread that is loading the
firmware will enable all the interrupts to make sure that
the driver gets the ALIVE interrupt.
The problem with that is that the thread that is loading
the firmware is actually racing against the ISR and we can
get to the following situation:

CPU0 CPU1
iwl_pcie_load_given_ucode
...
iwl_pcie_load_firmware_chunk
wait_for_interrupt
<interrupt>
ISR handles CSR_INT_BIT_FH_TX
ISR wakes up the thread on CPU0
/* enable all the interrupts
 * to get the ALIVE interrupt
 */
iwl_enable_interrupts
ISR re-enables CSR_INT_BIT_FH_TX only
/* start the firmware */
iwl_write32(trans, CSR_RESET, 0);

BUG! ALIVE interrupt will never arrive since it has been
masked by CPU1.

In order to fix that, change the ISR to first check if
STATUS_INT_ENABLED is set. If so, re-enable all the
interrupts. If STATUS_INT_ENABLED is clear, then we can
check what specific interrupt happened and re-enable only
that specific interrupt (RFKILL or FH_TX).

All the credit for the analysis goes to Kirtika who did the
actual debugging work.

Fixes: a6bd005fe92 ("iwlwifi: pcie: fix RF-Kill vs. firmware load race")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoiwlwifi: pcie: enable interrupts before releasing the NIC's CPU
Emmanuel Grumbach [Wed, 8 Jun 2016 20:07:31 +0000 (23:07 +0300)] 
iwlwifi: pcie: enable interrupts before releasing the NIC's CPU

commit 2aabdbdc17b7c53490337bfc58de3409c84d85d2 upstream.

The NIC's CPU gets started after the firmware has been
written to its memory. The first thing it does is to
send an interrupt to let the driver know that it is
running. In order to get that interrupt, the driver needs
to make sure it is not masked. Of course, the interrupt
needs to be enabled in the driver before the CPU starts to
run.
I mistakenly inversed those two steps leading to races
which prevented the driver from getting the alive interrupt
from the firmware.
Fix that.

Fixes: a6bd005fe92 ("iwlwifi: pcie: fix RF-Kill vs. firmware load race")
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agodm verity fec: fix block calculation
Sami Tolvanen [Tue, 21 Jun 2016 18:02:42 +0000 (11:02 -0700)] 
dm verity fec: fix block calculation

commit 602d1657c603eedd7379a8bcde1ad3a2972ecc5f upstream.

do_div was replaced with div64_u64 at some point, causing a bug with
block calculation due to incompatible semantics of the two functions.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Fixes: a739ff3f543a ("dm verity: add support for forward error correction")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agos5p-mfc: Add release callback for memory region devs
Javier Martinez Canillas [Tue, 3 May 2016 20:27:17 +0000 (16:27 -0400)] 
s5p-mfc: Add release callback for memory region devs

commit 6311f1261f59ce5e51fbe5cc3b5e7737197316ac upstream.

When s5p_mfc_remove() calls put_device() for the reserved memory region
devs, the driver core warns that the dev doesn't have a release callback:

WARNING: CPU: 0 PID: 591 at drivers/base/core.c:251 device_release+0x8c/0x90
Device 's5p-mfc-l' does not have a release() function, it is broken and must be fixed.

Also, the declared DMA memory using dma_declare_coherent_memory() isn't
relased so add a dev .release that calls dma_release_declared_memory().

Fixes: 6e83e6e25eb4 ("[media] s5p-mfc: Fix kernel warning on memory init")
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agos5p-mfc: Set device name for reserved memory region devs
Javier Martinez Canillas [Tue, 3 May 2016 20:27:16 +0000 (16:27 -0400)] 
s5p-mfc: Set device name for reserved memory region devs

commit 29debab0a94035a390801d1f177d171d014b7765 upstream.

The devices don't have a name set, so makes dev_name() returns NULL which
makes harder to identify the devices that are causing issues, for example:

WARNING: CPU: 2 PID: 616 at drivers/base/core.c:251 device_release+0x8c/0x90
Device '(null)' does not have a release() function, it is broken and must be fixed.

And after setting the device name:

WARNING: CPU: 0 PID: 591 at drivers/base/core.c:251 device_release+0x8c/0x90
Device 's5p-mfc-l' does not have a release() function, it is broken and must be fixed.

Fixes: 6e83e6e25eb4 ("[media] s5p-mfc: Fix kernel warning on memory init")
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agohp-wmi: Fix wifi cannot be hard-unblocked
Alex Hung [Mon, 13 Jun 2016 11:44:00 +0000 (19:44 +0800)] 
hp-wmi: Fix wifi cannot be hard-unblocked

commit fc8a601e1175ae351f662506030f9939cb7fdbfe upstream.

Several users reported wifi cannot be unblocked as discussed in [1].
This patch removes the use of the 2009 flag by BIOS but uses the actual
WMI function calls - it will be skipped if WMI reports unsupported.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=69131

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Tested-by: Evgenii Shatokhin <eugene.shatokhin@yandex.ru>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoxfs: bufferhead chains are invalid after end_page_writeback
Dave Chinner [Thu, 21 Jul 2016 23:56:38 +0000 (09:56 +1000)] 
xfs: bufferhead chains are invalid after end_page_writeback

commit 28b783e47ad702b8e0f4861ef94cdfce6abd7c80 upstream.

In xfs_finish_page_writeback(), we have a loop that looks like this:

        do {
                if (off < bvec->bv_offset)
                        goto next_bh;
                if (off > end)
                        break;
                bh->b_end_io(bh, !error);
next_bh:
                off += bh->b_size;
        } while ((bh = bh->b_this_page) != head);

The b_end_io function is end_buffer_async_write(), which will call
end_page_writeback() once all the buffers have marked as no longer
under IO.  This issue here is that the only thing currently
protecting both the bufferhead chain and the page from being
reclaimed is the PageWriteback state held on the page.

While we attempt to limit the loop to just the buffers covered by
the IO, we still read from the buffer size and follow the next
pointer in the bufferhead chain. There is no guarantee that either
of these are valid after the PageWriteback flag has been cleared.
Hence, loops like this are completely unsafe, and result in
use-after-free issues. One such problem was caught by Calvin Owens
with KASAN:

.....
 INFO: Freed in 0x103fc80ec age=18446651500051355200 cpu=2165122683 pid=-1
  free_buffer_head+0x41/0x90
  __slab_free+0x1ed/0x340
  kmem_cache_free+0x270/0x300
  free_buffer_head+0x41/0x90
  try_to_free_buffers+0x171/0x240
  xfs_vm_releasepage+0xcb/0x3b0
  try_to_release_page+0x106/0x190
  shrink_page_list+0x118e/0x1a10
  shrink_inactive_list+0x42c/0xdf0
  shrink_zone_memcg+0xa09/0xfa0
  shrink_zone+0x2c3/0xbc0
.....
 Call Trace:
  <IRQ>  [<ffffffff81e8b8e4>] dump_stack+0x68/0x94
  [<ffffffff8153a995>] print_trailer+0x115/0x1a0
  [<ffffffff81541174>] object_err+0x34/0x40
  [<ffffffff815436e7>] kasan_report_error+0x217/0x530
  [<ffffffff81543b33>] __asan_report_load8_noabort+0x43/0x50
  [<ffffffff819d651f>] xfs_destroy_ioend+0x3bf/0x4c0
  [<ffffffff819d69d4>] xfs_end_bio+0x154/0x220
  [<ffffffff81de0c58>] bio_endio+0x158/0x1b0
  [<ffffffff81dff61b>] blk_update_request+0x18b/0xb80
  [<ffffffff821baf57>] scsi_end_request+0x97/0x5a0
  [<ffffffff821c5558>] scsi_io_completion+0x438/0x1690
  [<ffffffff821a8d95>] scsi_finish_command+0x375/0x4e0
  [<ffffffff821c3940>] scsi_softirq_done+0x280/0x340

Where the access is occuring during IO completion after the buffer
had been freed from direct memory reclaim.

Prevent use-after-free accidents in this end_io processing loop by
pre-calculating the loop conditionals before calling bh->b_end_io().
The loop is already limited to just the bufferheads covered by the
IO in progress, so the offset checks are sufficient to prevent
accessing buffers in the chain after end_page_writeback() has been
called by the the bh->b_end_io() callout.

Yet another example of why Bufferheads Must Die.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reported-and-Tested-by: Calvin Owens <calvinowens@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agodm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING
Mike Snitzer [Tue, 2 Aug 2016 17:07:20 +0000 (13:07 -0400)] 
dm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING

commit eaf9a7361f47727b166688a9f2096854eef60fbe upstream.

Otherwise, there is potential for both DMF_SUSPENDED* and
DMF_NOFLUSH_SUSPENDING to not be set during dm_suspend() -- which is
definitely _not_ a valid state.

This fix, in conjuction with "dm rq: fix the starting and stopping of
blk-mq queues", addresses the potential for request-based DM multipath's
__multipath_map() to see !dm_noflush_suspending() during suspend.

Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agodm: fix second blk_delay_queue() parameter to be in msec units not jiffies
Tahsin Erdogan [Fri, 15 Jul 2016 13:27:08 +0000 (06:27 -0700)] 
dm: fix second blk_delay_queue() parameter to be in msec units not jiffies

commit bd9f55ea1cf6e14eb054b06ea877d2d1fa339514 upstream.

Commit d548b34b062 ("dm: reduce the queue delay used in dm_request_fn
from 100ms to 10ms") always intended the value to be 10 msecs -- it
just expressed it in jiffies because earlier commit 7eaceaccab ("block:
remove per-queue plugging") did.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fixes: d548b34b062 ("dm: reduce the queue delay used in dm_request_fn from 100ms to 10ms")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoregulator: s2mps11: Fix the voltage linear range for s2mps15
Alim Akhtar [Tue, 12 Jul 2016 05:56:43 +0000 (11:26 +0530)] 
regulator: s2mps11: Fix the voltage linear range for s2mps15

commit 04c16b84e49a6d609c88f4f5523237ece3612b74 upstream.

This patch fixes some of the LDOs and BUCKs voltage range as per
user manual of s2mps15 (REV0.4).

Fixes: 51af20675800 ("regulator: s2mps11: Add support for S2MPS15 regulators")
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agosur40: fix occasional oopses on device close
Florian Echtler [Tue, 31 May 2016 20:15:33 +0000 (17:15 -0300)] 
sur40: fix occasional oopses on device close

commit 6a8588156657e607fcfdffd46c1daae8ba88a1e5 upstream.

Closing the V4L2 device sometimes triggers a kernel oops.
Present patch fixes this.

Signed-off-by: Martin Kaltenbrunner <modin@yuri.at>
Signed-off-by: Florian Echtler <floe@butterbrot.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agosur40: lower poll interval to fix occasional FPS drops to ~56 FPS
Florian Echtler [Tue, 31 May 2016 20:15:32 +0000 (17:15 -0300)] 
sur40: lower poll interval to fix occasional FPS drops to ~56 FPS

commit af766ee005c496b8567976dc3eed7676443ed6de upstream.

The framerate sometimes drops below 60 Hz if the poll interval is too high.
Lowering it to the minimum of 1 ms fixes this.

Signed-off-by: Martin Kaltenbrunner <modin@yuri.at>
Signed-off-by: Florian Echtler <floe@butterbrot.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoFix RC5 decoding with Fintek CIR chipset
Jonathan McDowell [Sat, 14 May 2016 17:01:26 +0000 (14:01 -0300)] 
Fix RC5 decoding with Fintek CIR chipset

commit bbdb34c90aeb8b2253eae88029788ebe1d7f2fd4 upstream.

Fix RC5 decoding with Fintek CIR chipset

Commit e87b540be2dd02552fb9244d50ae8b4e4619a34b tightened up the RC5
decoding by adding a check for trailing silence to ensure a valid RC5
command had been received. Unfortunately the trailer length checked was
10 units and the Fintek CIR device does not want to provide details of a
space longer than 6350us. This meant that RC5 remotes working on a
Fintek setup on 3.16 failed on 3.17 and later. Fix this by shortening
the trailer check to 6 units (allowing for a previous space in the
received remote command).

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=117221

Signed-off-by: Jonathan McDowell <noodles@earth.li>
Signed-off-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agovb2: core: Skip planes array verification if pb is NULL
Sakari Ailus [Wed, 11 May 2016 21:44:32 +0000 (18:44 -0300)] 
vb2: core: Skip planes array verification if pb is NULL

commit 126f40298446a82116e1f92a1aaf72b8c8228fae upstream.

An earlier patch fixing an input validation issue introduced another
issue: vb2_core_dqbuf() is called with pb argument value NULL in some
cases, causing a NULL pointer dereference. Fix this by skipping the
verification as there's nothing to verify.

Fixes: e7e0c3e26587 ("[media] videobuf2-core: Check user space planes array in dqbuf")
Signed-off-by: David R <david@unsolicited.net>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agovideobuf2-v4l2: Verify planes array in buffer dequeueing
Sakari Ailus [Sun, 3 Apr 2016 19:31:03 +0000 (16:31 -0300)] 
videobuf2-v4l2: Verify planes array in buffer dequeueing

commit 83934b75c368f529d084815c463a7ef781dc9751 upstream.

When a buffer is being dequeued using VIDIOC_DQBUF IOCTL, the exact buffer
which will be dequeued is not known until the buffer has been removed from
the queue. The number of planes is specific to a buffer, not to the queue.

This does lead to the situation where multi-plane buffers may be requested
and queued with n planes, but VIDIOC_DQBUF IOCTL may be passed an argument
struct with fewer planes.

__fill_v4l2_buffer() however uses the number of planes from the dequeued
videobuf2 buffer, overwriting kernel memory (the m.planes array allocated
in video_usercopy() in v4l2-ioctl.c)  if the user provided fewer
planes than the dequeued buffer had. Oops!

Fixes: b0e0e1f83de3 ("[media] media: videobuf2: Prepare to divide videobuf2")
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agorc: nuvoton: fix hang if chip is configured for alternative EFM IO address
Heiner Kallweit [Thu, 7 Jul 2016 06:17:39 +0000 (03:17 -0300)] 
rc: nuvoton: fix hang if chip is configured for alternative EFM IO address

commit 5cac1f67ea0363d463a58ec2d9118268fe2ba5d6 upstream.

If a system configures the Nuvoton chip to use the alternative
EFM IO address (CR_EFIR2) then after probing the primary EFM IO
address (CR_EFIR) this region is not released.

If a driver for another function of the Nuvoton Super I/O
chip uses the same probing mechanism then it will hang if
loaded after the nuvoton-cir driver.
This was reported for the nct6775 hwmon driver.

Fix this by properly releasing the region after probing CR_EFIR.
This regression was introduced with kernel 4.6 so cc it to stable.

Reported-by: Antti Seppälä <a.seppala@gmail.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Tested-by: Antti Seppälä <a.seppala@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agomedia: dvb_ringbuffer: Add memory barriers
Soeren Moch [Wed, 11 May 2016 16:49:11 +0000 (13:49 -0300)] 
media: dvb_ringbuffer: Add memory barriers

commit ca6e6126db5494f18c6c6615060d4d803b528bff upstream.

Implement memory barriers according to Documentation/circular-buffers.txt:
- use smp_store_release() to update ringbuffer read/write pointers
- use smp_load_acquire() to load write pointer on reader side
- use ACCESS_ONCE() to load read pointer on writer side

This fixes data stream corruptions observed e.g. on an ARM Cortex-A9
quad core system with different types (PCI, USB) of DVB tuners.

Signed-off-by: Soeren Moch <smoch@web.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agomedia: usbtv: prevent access to free'd resources
Matthew Leach [Fri, 8 Jul 2016 12:04:27 +0000 (09:04 -0300)] 
media: usbtv: prevent access to free'd resources

commit 2a00932f082aff93c3a55426e0c7af6d0ec03997 upstream.

When disconnecting the usbtv device, the sound card is unregistered
from ALSA and the snd member of the usbtv struct is set to NULL.  If
the usbtv snd_trigger work is running, this can cause a race condition
where the kernel will attempt to access free'd resources, shown in
[1].

This patch fixes the disconnection code by cancelling any snd_trigger
work before unregistering the sound card from ALSA and checking that
the snd member still exists in the work function.

[1]:
 usb 3-1.2: USB disconnect, device number 6
 BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
 IP: [<ffffffff81093850>] process_one_work+0x30/0x480
 PGD 405bbf067 PUD 405bbe067 PMD 0
 Call Trace:
  [<ffffffff81093ce8>] worker_thread+0x48/0x4e0
  [<ffffffff81093ca0>] ? process_one_work+0x480/0x480
  [<ffffffff81093ca0>] ? process_one_work+0x480/0x480
  [<ffffffff81099998>] kthread+0xd8/0xf0
  [<ffffffff815c73c2>] ret_from_fork+0x22/0x40
  [<ffffffff810998c0>] ? kthread_worker_fn+0x170/0x170
 ---[ end trace 0f3dac5c1a38e610 ]---

Signed-off-by: Matthew Leach <matthew@mattleach.net>
Tested-by: Peter Sutton <foxxy@foxdogstudios.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoobjtool: Add 'fixdep' to objtool/.gitignore
Paul Gortmaker [Mon, 25 Jul 2016 13:19:31 +0000 (08:19 -0500)] 
objtool: Add 'fixdep' to objtool/.gitignore

commit 5cada17426505b09a045cd9e6d7fb6db19b76ea1 upstream.

To fix:

   Untracked files:
     (use "git add <file>..." to include in what will be committed)

           tools/objtool/fixdep

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a4571f6893caf737d05524cfa3829c2abc1fb240.1469452729.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoperf/x86/intel/uncore: Fix uncore num_counters
Kan Liang [Thu, 11 Aug 2016 14:30:20 +0000 (07:30 -0700)] 
perf/x86/intel/uncore: Fix uncore num_counters

commit 10e9e7bd598f9a66a11a22514c68c13c41fc821b upstream.

Some uncore boxes' num_counters value for Haswell server and
Broadwell server are not correct (too large, off by one).

This issue was found by comparing the code with the document. Although
there is no bug report from users yet, accessing non-existent counters
is dangerous and the behavior is undefined: it may cause miscounting or
even crashes.

This patch makes them consistent with the uncore document.

Reported-by: Lukasz Odzioba <lukasz.odzioba@intel.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1470925820-59847-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agomfd: qcom_rpm: Parametrize also ack selector size
Linus Walleij [Wed, 22 Jun 2016 06:27:17 +0000 (08:27 +0200)] 
mfd: qcom_rpm: Parametrize also ack selector size

commit f37be01e6dc606f2fcc5e95c9933d948ce19bd35 upstream.

The RPM has two sets of selectors (IPC bit fields): request and
acknowledge. Apparently, some models use 4*32 bit words for select
and some use 7*32 bit words for request, but all use 7*32 words
for acknowledge bits.

So apparently you can on the models with requests of 4*32 select
bits send 4*32 messages and get 7*32 different replies, so on ACK
interrupt, 7*32 bit words need to be read. This is how the vendor
code apparently works.

Reported-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agomfd: qcom_rpm: Fix offset error for msm8660
Linus Walleij [Tue, 14 Jun 2016 23:02:26 +0000 (01:02 +0200)] 
mfd: qcom_rpm: Fix offset error for msm8660

commit 9835f1b70bb3890d38308b9be4fb9d7451ba67f1 upstream.

The RPM in MSM8660/APQ8060 has different offsets to the selector
ACK and request context ACK registers. Make all these register
offsets part of the per-SoC data and assign the right values.

The bug was found by verifying backwards to the vendor tree in
the out-of-tree files <mach/rpm-[8660|8064|8960]>: all were using
offsets 3,11,15,23 and a select size of 4, except the MSM8660/APQ8060
which was using offsets 3,11,19,27 and a select size of 7.

All other platforms apart from msm8660 were affected by reading
excess registers, since 7 was hardcoded as the number of select
words, this patch makes also this part dynamic so we only write/read
as many select words as the platform actually use.

Symptoms of this bug when using msm8660: the first RPM transaction
would work, but the next would stall or raise an error since the
previous transaction was not properly ACKed as the ACK words were
read at the wrong offset.

Fixes: 58e214382bdd ("mfd: qcom-rpm: Driver for the Qualcomm RPM")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Björn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agointel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()
Jan Kiszka [Fri, 8 Jul 2016 18:42:04 +0000 (20:42 +0200)] 
intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()

commit 5fc8f707a2aa40c767c3a338738b9b6fcd151ac1 upstream.

If MSR_CONFIG_TDP_CONTROL is locked, we currently try to address some
MSR 0x80000648 or so. Mask out the relevant level bits 0 and 1.

Found while running over the Jailhouse hypervisor which became upset
about this strange MSR index.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agos390/mm: don't drop errors in get_guest_storage_key
David Hildenbrand [Tue, 10 May 2016 11:51:54 +0000 (13:51 +0200)] 
s390/mm: don't drop errors in get_guest_storage_key

commit c427c42cd612719e8fb8b5891cc9761e7770024e upstream.

Commit 1e133ab296f3 ("s390/mm: split arch/s390/mm/pgtable.c") changed
the return value of get_guest_storage_key to an unsigned char, resulting
in -EFAULT getting interpreted as a valid storage key.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agos390/mm: fix gmap tlb flush issues
David Hildenbrand [Thu, 7 Jul 2016 08:44:10 +0000 (10:44 +0200)] 
s390/mm: fix gmap tlb flush issues

commit f045402984404ddc11016358411e445192919047 upstream.

__tlb_flush_asce() should never be used if multiple asce belong to a mm.

As this function changes mm logic determining if local or global tlb
flushes will be neded, we might end up flushing only the gmap asce on all
CPUs and a follow up mm asce flushes will only flush on the local CPU,
although that asce ran on multiple CPUs.

The missing tlb flushes will provoke strange faults in user space and even
low address protections in user space, crashing the kernel.

Fixes: 1b948d6caec4 ("s390/mm,tlb: optimize TLB flushing for zEC12")
Reported-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agos390/cio: allow to reset channel measurement block
Sebastian Ott [Tue, 12 Jul 2016 17:57:57 +0000 (19:57 +0200)] 
s390/cio: allow to reset channel measurement block

commit 0f5d050ceaa31b2229102211d60c149f920df3aa upstream.

Prior to commit 1bc6664bdfb949bc69a08113801e7d6acbf6bc3f a call to
enable_cmf for a device for which channel measurement was already
enabled resulted in a reset of the measurement data.

What looked like bugs at the time (a 2nd allocation was triggered
but failed, reset was called regardless of previous failures, and
errors have not been reported to userspace) was actually something
at least one userspace tool depended on. Restore that behavior in
a sane way.

Fixes: 1bc6664bdfb ("s390/cio: use device_lock during cmb activation")
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoKVM: x86: avoid simultaneous queueing of both IRQ and SMI
Paolo Bonzini [Wed, 1 Jun 2016 20:26:00 +0000 (22:26 +0200)] 
KVM: x86: avoid simultaneous queueing of both IRQ and SMI

commit c43203cab1e2e193c43f8295f01dfb2a0721d9e5 upstream.

If the processor exits to KVM while delivering an interrupt,
the hypervisor then requeues the interrupt for the next vmentry.
Trying to enter SMM in this same window causes to enter non-root
mode in emulated SMM (i.e. with IF=0) and with a request to
inject an IRQ (i.e. with a valid VM-entry interrupt info field).
This is invalid guest state (SDM 26.3.1.4 "Check on Guest RIP
and RFLAGS") and the processor fails vmentry.

The fix is to defer the injection from KVM_REQ_SMI to KVM_REQ_EVENT,
like we already do for e.g. NMIs.  This patch doesn't change the
name of the process_smi function so that it can be applied to
stable releases.  The next patch will modify the names so that
process_nmi and process_smi handle respectively KVM_REQ_NMI and
KVM_REQ_SMI.

This is especially common with Windows, probably due to the
self-IPI trick that it uses to deliver deferred procedure
calls (DPCs).

Reported-by: Laszlo Ersek <lersek@redhat.com>
Reported-by: Michał Zegan <webczat_200@poczta.onet.pl>
Fixes: 64d6067057d9658acb8675afcfba549abdb7fc16
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoKVM: nVMX: Fix memory corruption when using VMCS shadowing
Jim Mattson [Fri, 8 Jul 2016 22:36:06 +0000 (15:36 -0700)] 
KVM: nVMX: Fix memory corruption when using VMCS shadowing

commit 2f1fe81123f59271bddda673b60116bde9660385 upstream.

When freeing the nested resources of a vcpu, there is an assumption that
the vcpu's vmcs01 is the current VMCS on the CPU that executes
nested_release_vmcs12(). If this assumption is violated, the vcpu's
vmcs01 may be made active on multiple CPUs at the same time, in
violation of Intel's specification. Moreover, since the vcpu's vmcs01 is
not VMCLEARed on every CPU on which it is active, it can linger in a
CPU's VMCS cache after it has been freed and potentially
repurposed. Subsequent eviction from the CPU's VMCS cache on a capacity
miss can result in memory corruption.

It is not sufficient for vmx_free_vcpu() to call vmx_load_vmcs01(). If
the vcpu in question was last loaded on a different CPU, it must be
migrated to the current CPU before calling vmx_load_vmcs01().

Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoKVM: VMX: handle PML full VMEXIT that occurs during event delivery
Cao, Lei [Fri, 15 Jul 2016 13:54:04 +0000 (13:54 +0000)] 
KVM: VMX: handle PML full VMEXIT that occurs during event delivery

commit b244c9fc251e14a083a1cbf04bef10bd99303a76 upstream.

With PML enabled, guest will shut down if a PML full VMEXIT occurs during
event delivery. According to Intel SDM 27.2.3, PML full VMEXIT can occur when
event is being delivered through IDT, so KVM should not exit to user space
with error. Instead, it should let EXIT_REASON_PML_FULL go through and the
event will be re-injected on the next VMENTRY.

Signed-off-by: Lei Cao <lei.cao@stratus.com>
Fixes: 843e4330573c ("KVM: VMX: Add PML support in VMX")
[Shortened the summary and Cc'd stable.]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoKVM: MTRR: fix kvm_mtrr_check_gfn_range_consistency page fault
Alexis Dambricourt [Mon, 4 Jul 2016 19:05:15 +0000 (21:05 +0200)] 
KVM: MTRR: fix kvm_mtrr_check_gfn_range_consistency page fault

commit 30b072ce0356e8b141f4ca6da7220486fa3641d9 upstream.

The following #PF may occurs:
[ 1403.317041] BUG: unable to handle kernel paging request at 0000000200000068
[ 1403.317045] IP: [<ffffffffc04c20b0>] __mtrr_lookup_var_next+0x10/0xa0 [kvm]

[ 1403.317123] Call Trace:
[ 1403.317134]  [<ffffffffc04c2a65>] ? kvm_mtrr_check_gfn_range_consistency+0xc5/0x120 [kvm]
[ 1403.317143]  [<ffffffffc04ac11f>] ? tdp_page_fault+0x9f/0x2c0 [kvm]
[ 1403.317152]  [<ffffffffc0498128>] ? kvm_set_msr_common+0x858/0xc00 [kvm]
[ 1403.317161]  [<ffffffffc04b8883>] ? x86_emulate_insn+0x273/0xd30 [kvm]
[ 1403.317171]  [<ffffffffc04c04e4>] ? kvm_cpuid+0x34/0x190 [kvm]
[ 1403.317180]  [<ffffffffc04a5bb9>] ? kvm_mmu_page_fault+0x59/0xe0 [kvm]
[ 1403.317183]  [<ffffffffc0d729e1>] ? vmx_handle_exit+0x1d1/0x14a0 [kvm_intel]
[ 1403.317185]  [<ffffffffc0d75f3f>] ? atomic_switch_perf_msrs+0x6f/0xa0 [kvm_intel]
[ 1403.317187]  [<ffffffffc0d7621d>] ? vmx_vcpu_run+0x2ad/0x420 [kvm_intel]
[ 1403.317196]  [<ffffffffc04a0962>] ? kvm_arch_vcpu_ioctl_run+0x622/0x1550 [kvm]
[ 1403.317204]  [<ffffffffc049abb9>] ? kvm_arch_vcpu_load+0x59/0x210 [kvm]
[ 1403.317206]  [<ffffffff81036245>] ? __kernel_fpu_end+0x35/0x100
[ 1403.317213]  [<ffffffffc0487eb6>] ? kvm_vcpu_ioctl+0x316/0x5d0 [kvm]
[ 1403.317215]  [<ffffffff81088225>] ? do_sigtimedwait+0xd5/0x220
[ 1403.317217]  [<ffffffff811f84dd>] ? do_vfs_ioctl+0x9d/0x5c0
[ 1403.317224]  [<ffffffffc04928ae>] ? kvm_on_user_return+0x3e/0x70 [kvm]
[ 1403.317225]  [<ffffffff811f8a74>] ? SyS_ioctl+0x74/0x80
[ 1403.317227]  [<ffffffff815bf0b6>] ? entry_SYSCALL_64_fastpath+0x1e/0xa8
[ 1403.317242] RIP  [<ffffffffc04c20b0>] __mtrr_lookup_var_next+0x10/0xa0 [kvm]

At mtrr_lookup_fixed_next(), when the condition
'if (iter->index >= ARRAY_SIZE(iter->mtrr_state->fixed_ranges))' becomes true,
mtrr_lookup_var_start() is called with iter->range with gargabe values from the
fixed MTRR union field. Then, list_prepare_entry() do not call list_entry()
initialization, keeping a garbage pointer in iter->range which is accessed in
the following __mtrr_lookup_var_next() call.

Fixes: f571c0973e4b8c888e049b6842e4b4f93b5c609c
Signed-off-by: Alexis Dambricourt <alexis@blade-group.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoKVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
Paul Mackerras [Wed, 22 Jun 2016 05:52:55 +0000 (15:52 +1000)] 
KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE

commit 93d17397e4e2182fdaad503e2f9da46202c0f1c3 upstream.

It turns out that if the guest does a H_CEDE while the CPU is in
a transactional state, and the H_CEDE does a nap, and the nap
loses the architected state of the CPU (which is is allowed to do),
then we lose the checkpointed state of the virtual CPU.  In addition,
the transactional-memory state recorded in the MSR gets reset back
to non-transactional, and when we try to return to the guest, we take
a TM bad thing type of program interrupt because we are trying to
transition from non-transactional to transactional with a hrfid
instruction, which is not permitted.

The result of the program interrupt occurring at that point is that
the host CPU will hang in an infinite loop with interrupts disabled.
Thus this is a denial of service vulnerability in the host which can
be triggered by any guest (and depending on the guest kernel, it can
potentially triggered by unprivileged userspace in the guest).

This vulnerability has been assigned the ID CVE-2016-5412.

To fix this, we save the TM state before napping and restore it
on exit from the nap, when handling a H_CEDE in real mode.  The
case where H_CEDE exits to host virtual mode is already OK (as are
other hcalls which exit to host virtual mode) because the exit
path saves the TM state.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoKVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
Paul Mackerras [Wed, 22 Jun 2016 04:21:59 +0000 (14:21 +1000)] 
KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures

commit f024ee098476a3e620232e4a78cfac505f121245 upstream.

This moves the transactional memory state save and restore sequences
out of the guest entry/exit paths into separate procedures.  This is
so that these sequences can be used in going into and out of nap
in a subsequent patch.

The only code changes here are (a) saving and restore LR on the
stack, since these new procedures get called with a bl instruction,
(b) explicitly saving r1 into the PACA instead of assuming that
HSTATE_HOST_R1(r13) is already set, and (c) removing an unnecessary
and redundant setting of MSR[TM] that should have been removed by
commit 9d4d0bdd9e0a ("KVM: PPC: Book3S HV: Add transactional memory
support", 2013-09-24) but wasn't.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: hibernate: handle allocation failures
Mark Rutland [Thu, 11 Aug 2016 13:11:06 +0000 (14:11 +0100)] 
arm64: hibernate: handle allocation failures

commit dfbca61af0b654990b9af8297ac574a9986d8275 upstream.

In create_safe_exec_page(), we create a copy of the hibernate exit text,
along with some page tables to map this via TTBR0. We then install the
new tables in TTBR0.

In swsusp_arch_resume() we call create_safe_exec_page() before trying a
number of operations which may fail (e.g. copying the linear map page
tables). If these fail, we bail out of swsusp_arch_resume() and return
an error code, but leave TTBR0 as-is. Subsequently, the core hibernate
code will call free_basic_memory_bitmaps(), which will free all of the
memory allocations we made, including the page tables installed in
TTBR0.

Thus, we may have TTBR0 pointing at dangling freed memory for some
period of time. If the hibernate attempt was triggered by a user
requesting a hibernate test via the reboot syscall, we may return to
userspace with the clobbered TTBR0 value.

Avoid these issues by reorganising swsusp_arch_resume() such that we
have no failure paths after create_safe_exec_page(). We also add a check
that the zero page allocation succeeded, matching what we have for other
allocations.

Fixes: 82869ac57b5d ("arm64: kernel: Add support for hibernate/suspend-to-disk")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: James Morse <james.morse@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: hibernate: avoid potential TLB conflict
Mark Rutland [Thu, 11 Aug 2016 13:11:05 +0000 (14:11 +0100)] 
arm64: hibernate: avoid potential TLB conflict

commit 0194e760f7d2f42adb5e1db31b27a4331dd89c2f upstream.

In create_safe_exec_page we install a set of global mappings in TTBR0,
then subsequently invalidate TLBs. While TTBR0 points at the zero page,
and the TLBs should be free of stale global entries, we may have stale
ASID-tagged entries (e.g. from the EFI runtime services mappings) for
the same VAs. Per the ARM ARM these ASID-tagged entries may conflict
with newly-allocated global entries, and we must follow a
Break-Before-Make approach to avoid issues resulting from this.

This patch reworks create_safe_exec_page to invalidate TLBs while the
zero page is still in place, ensuring that there are no potential
conflicts when the new TTBR0 value is installed. As a single CPU is
online while this code executes, we do not need to perform broadcast TLB
maintenance, and can call local_flush_tlb_all(), which also subsumes
some barriers. The remaining assembly is converted to use write_sysreg()
and isb().

Other than this, we safely manipulate TTBRs in the hibernate dance. The
code we install as part of the new TTBR0 mapping (the hibernated
kernel's swsusp_arch_suspend_exit) installs a zero page into TTBR1,
invalidates TLBs, then installs its preferred value. Upon being restored
to the middle of swsusp_arch_suspend, the new image will call
__cpu_suspend_exit, which will call cpu_uninstall_idmap, installing the
zero page in TTBR0 and invalidating all TLB entries.

Fixes: 82869ac57b5d ("arm64: kernel: Add support for hibernate/suspend-to-disk")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: KVM: Set cpsr before spsr on fault injection
Andrew Jones [Fri, 22 Jul 2016 14:38:46 +0000 (10:38 -0400)] 
arm64: KVM: Set cpsr before spsr on fault injection

commit 89581f06b2bc225f0c9822fa52e714aa2e3810dd upstream.

We need to set cpsr before determining the spsr bank, as the bank
depends on the target exception level of the injection, not the
current mode of the vcpu. Normally this is one in the same (EL1),
but not when we manage to trap an EL0 fault. It still doesn't really
matter for the 64-bit EL0 case though, as vcpu_spsr() unconditionally
uses the EL1 bank for that. However the 32-bit EL0 case gets fun, as
that path will lead to the BUG() in vcpu_spsr32().

This patch fixes the assignment order and also modifies some white
space in order to better group pairs of lines that have strict order.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: vmlinux.lds: make __rela_offset and __dynsym_offset ABSOLUTE
Ard Biesheuvel [Thu, 28 Jul 2016 14:15:14 +0000 (16:15 +0200)] 
arm64: vmlinux.lds: make __rela_offset and __dynsym_offset ABSOLUTE

commit d6732fc402c2665f61e72faf206a0268e65236e9 upstream.

Due to the untyped KIMAGE_VADDR constant, the linker may not notice
that the __rela_offset and __dynsym_offset expressions are absolute
values (i.e., are not subject to relocation). This does not matter for
KASLR, but it does confuse kallsyms in relative mode, since it uses
the lowest non-absolute symbol address as the anchor point, and expects
all other symbol addresses to be within 4 GB of it.

Fix this by qualifying these expressions as ABSOLUTE() explicitly.

Fixes: 0cd3defe0af4 ("arm64: kernel: perform relocation processing from ID map")
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: mm: avoid fdt_check_header() before the FDT is fully mapped
Ard Biesheuvel [Mon, 1 Aug 2016 11:29:31 +0000 (13:29 +0200)] 
arm64: mm: avoid fdt_check_header() before the FDT is fully mapped

commit 04a848106193b134741672f7e4e444b50c70b631 upstream.

As reported by Zijun, the fdt_check_header() call in __fixmap_remap_fdt()
is not safe since it is not guaranteed that the FDT header is mapped
completely. Due to the minimum alignment of 8 bytes, the only fields we
can assume to be mapped are 'magic' and 'totalsize'.

Since the OF layer is in charge of validating the FDT image, and we are
only interested in making reasonably sure that the size field contains
a meaningful value, replace the fdt_check_header() call with an explicit
comparison of the magic field's value against the expected value.

Reported-by: Zijun Hu <zijun_hu@htc.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: dts: rockchip: fixes the gic400 2nd region size for rk3368
Caesar Wang [Wed, 18 May 2016 14:41:50 +0000 (22:41 +0800)] 
arm64: dts: rockchip: fixes the gic400 2nd region size for rk3368

commit ad1cfdf518976447e6b0d31517bad4e3ebbce6bb upstream.

The 2nd additional region is the GIC virtual cpu interface register
base and size.

As the gic400 of rk3368 says, the cpu interface register map as below

:

-0x0000 GICC_CTRL
.
.
.
-0x00fc GICC_IIDR
-0x1000 GICC_IDR

Obviously, the region size should be greater than 0x1000.
So we should make sure to include the GICC_IDR since the kernel will access
it in some cases.

Fixes: b790c2cab5ca ("arm64: dts: add Rockchip rk3368 core dtsi and board dts for the r88 board")
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[added Fixes and stable-cc]
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
8 years agopinctrl: cherryview: prevent concurrent access to GPIO controllers
Dan O'Donovan [Fri, 10 Jun 2016 12:23:34 +0000 (13:23 +0100)] 
pinctrl: cherryview: prevent concurrent access to GPIO controllers

commit 0bd50d719b004110e791800450ad204399100a86 upstream.

Due to a silicon issue on the Atom X5-Z8000 "Cherry Trail" processor
series, a common lock must be used to prevent concurrent accesses
across the 4 GPIO controllers managed by this driver.

See Intel Atom Z8000 Processor Series Specification Update
(Rev. 005), errata #CHT34, for further information.

Signed-off-by: Dan O'Donovan <dan@emutex.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agogpio: intel-mid: switch to devm_gpiochip_add_data()
Andy Shevchenko [Sun, 19 Jun 2016 20:49:57 +0000 (23:49 +0300)] 
gpio: intel-mid: switch to devm_gpiochip_add_data()

commit dd3b204af11b50be6dc77e18b88b3c646bba354c upstream.

The error handling is not correct since the commit 3f7dbfd8eea9 ("gpio:
intel-mid: switch to using gpiolib irqchip helpers"). Switch to devres API to
fix the potential resource leak.

Fixes: commit 3f7dbfd8eea9 ("gpio: intel-mid: switch to using gpiolib irqchip helpers")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agogpio: intel-mid: Remove potentially harmful code
Andy Shevchenko [Wed, 6 Jul 2016 09:50:12 +0000 (12:50 +0300)] 
gpio: intel-mid: Remove potentially harmful code

commit 3dbd3212f81b2b410a34a922055e2da792864829 upstream.

The commit d56d6b3d7d69 ("gpio: langwell: add Intel Merrifield support")
doesn't look at all as a proper support for Intel Merrifield and I dare to say
that it distorts the behaviour of the hardware.

The register map is different on Intel Merrifield, i.e. only 6 out of 8
register have the same purpose but none of them has same location in the
address space. The current case potentially harmful to existing hardware since
it's poking registers on wrong offsets and may set some pin to be GPIO output
when connected hardware doesn't expect such.

Besides the above GPIO and pinctrl on Intel Merrifield have been located in
different IP blocks. The functionality has been extended as well, i.e. added
support of level interrupts, special registers for wake capable sources and
thus, in my opinion, requires a completele separate driver.

If someone wondering the existing gpio-intel-mid.c would be converted to actual
pinctrl (which by the fact it is now), though I wouldn't be a volunteer to do
that.

Fixes: d56d6b3d7d69 ("gpio: langwell: add Intel Merrifield support")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agogpio: pca953x: Fix NBANK calculation for PCA9536
Vignesh R [Thu, 9 Jun 2016 05:32:04 +0000 (11:02 +0530)] 
gpio: pca953x: Fix NBANK calculation for PCA9536

commit a246b8198f776a16d1d3a3bbfc2d437bad766b29 upstream.

NBANK() macro assumes that ngpios is a multiple of 8(BANK_SZ) and
hence results in 0 banks for PCA9536 which has just 4 gpios. This is
wrong as PCA9356 has 1 bank with 4 gpios. This results in uninitialized
PCA953X_INVERT register. Fix this by using DIV_ROUND_UP macro in
NBANK().

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agotty/serial: atmel: fix RS485 half duplex with DMA
Alexandre Belloni [Fri, 27 May 2016 22:54:08 +0000 (00:54 +0200)] 
tty/serial: atmel: fix RS485 half duplex with DMA

commit 0058f0871efe7b01c6f2b3046c68196ab73e96da upstream.

When using DMA, half duplex doesn't work properly because rx is not stopped
before starting tx. Ensure we call atmel_stop_rx() in the DMA case.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoserial: samsung: Fix ERR pointer dereference on deferred probe
Krzysztof Kozlowski [Thu, 16 Jun 2016 06:27:35 +0000 (08:27 +0200)] 
serial: samsung: Fix ERR pointer dereference on deferred probe

commit e51e4d8a185de90424b03f30181b35f29c46a25a upstream.

When the clk_get() of "uart" clock returns EPROBE_DEFER, the next re-probe
finishes with success but uses invalid (ERR_PTR) values.  This leads to
dereferencing of ERR_PTR stored under ourport->clk:

12c30000.serial: Controller clock not found
(...)
12c30000.serial: ttySAC3 at MMIO 0x12c30000 (irq = 61, base_baud = 0) is a S3C6400/10
Unable to handle kernel paging request at virtual address fffffdfb

(clk_prepare) from [<c039f7d0>] (s3c24xx_serial_pm+0x20/0x128)
(s3c24xx_serial_pm) from [<c0395414>] (uart_change_pm+0x38/0x40)
(uart_change_pm) from [<c039689c>] (uart_add_one_port+0x31c/0x44c)
(uart_add_one_port) from [<c03a035c>] (s3c24xx_serial_probe+0x2a8/0x418)
(s3c24xx_serial_probe) from [<c03ee110>] (platform_drv_probe+0x50/0xb0)
(platform_drv_probe) from [<c03ecb44>] (driver_probe_device+0x1f4/0x2b0)
(driver_probe_device) from [<c03eb0c0>] (bus_for_each_drv+0x44/0x8c)
(bus_for_each_drv) from [<c03ec8c8>] (__device_attach+0x9c/0x100)
(__device_attach) from [<c03ebf54>] (bus_probe_device+0x84/0x8c)
(bus_probe_device) from [<c03ec388>] (deferred_probe_work_func+0x60/0x8c)
(deferred_probe_work_func) from [<c012fee4>] (process_one_work+0x120/0x328)
(process_one_work) from [<c0130150>] (worker_thread+0x2c/0x4ac)
(worker_thread) from [<c0135320>] (kthread+0xd8/0xf4)
(kthread) from [<c0107978>] (ret_from_fork+0x14/0x3c)

The first unsuccessful clk_get() causes s3c24xx_serial_init_port() to
exit with failure but the s3c24xx_uart_port is left half-configured
(e.g. port->mapbase is set, clk contains ERR_PTR).  On next re-probe,
the function s3c24xx_serial_init_port() will exit early with success
because of configured port->mapbase and driver will use old values,
including the ERR_PTR as clock.

Fix this by cleaning the port->mapbase on error path so each re-probe
will initialize all of the port settings.

Fixes: 60e93575476f ("serial: samsung: enable clock before clearing pending interrupts during init")
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agotty: serial: msm: Don't read off end of tx fifo
Bjorn Andersson [Fri, 3 Jun 2016 00:48:28 +0000 (17:48 -0700)] 
tty: serial: msm: Don't read off end of tx fifo

commit 30acf549ca1e81859a67590ab9ecfce3d1050a0b upstream.

For dm uarts in pio mode tx data is transferred to the fifo register 4
bytes at a time, but care is not taken when these 4 bytes spans the end
of the xmit buffer so the loop might read up to 3 bytes past the buffer
and then skip the actual data at the beginning of the buffer.

Fix this by, analogous to the DMA case, make sure the chunk doesn't
wrap the xmit buffer.

Fixes: 3a878c430fd6 ("tty: serial: msm: Add TX DMA support")
Cc: Ivan Ivanov <iivanov.xz@gmail.com>
Reported-by: Frank Rowand <frowand.list@gmail.com>
Reported-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Andy Gross <andy.gross@linaro.org>
Tested-by: Frank Rowand <frank.rowand@am.sony.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: Honor nosmp kernel command line option
Suzuki K Poulose [Thu, 21 Jul 2016 10:15:27 +0000 (11:15 +0100)] 
arm64: Honor nosmp kernel command line option

commit e75118a7b581b19b08282c7819c1ec6f68b91b79 upstream.

Passing "nosmp" should boot the kernel with a single processor, without
provision to enable secondary CPUs even if they are present. "nosmp" is
implemented by setting maxcpus=0. At the moment we still mark the secondary
CPUs present even with nosmp, which allows the userspace to bring them
up. This patch corrects the smp_prepare_cpus() to honor the maxcpus == 0.

Commit 44dbcc93ab67145 ("arm64: Fix behavior of maxcpus=N") fixed the
behavior for maxcpus >= 1, but broke maxcpus = 0.

Fixes: 44dbcc93ab67 ("arm64: Fix behavior of maxcpus=N")
Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
[catalin.marinas@arm.com: updated code comment]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: Only select ARM64_MODULE_PLTS if MODULES=y
Catalin Marinas [Tue, 26 Jul 2016 17:16:55 +0000 (10:16 -0700)] 
arm64: Only select ARM64_MODULE_PLTS if MODULES=y

commit b9c220b589daaf140f5b8ebe502c98745b94e65c upstream.

Selecting CONFIG_RANDOMIZE_BASE=y and CONFIG_MODULES=n fails to build
the module PLTs support:

  CC      arch/arm64/kernel/module-plts.o
/work/Linux/linux-2.6-aarch64/arch/arm64/kernel/module-plts.c: In function ‘module_emit_plt_entry’:
/work/Linux/linux-2.6-aarch64/arch/arm64/kernel/module-plts.c:32:49: error: dereferencing pointer to incomplete type ‘struct module’

This patch selects ARM64_MODULE_PLTS conditionally only if MODULES is
enabled.

Fixes: f80fb3a3d508 ("arm64: add support for kernel ASLR")
Reported-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: Fix incorrect per-cpu usage for boot CPU
Suzuki K Poulose [Thu, 21 Jul 2016 10:12:55 +0000 (11:12 +0100)] 
arm64: Fix incorrect per-cpu usage for boot CPU

commit 9113c2aa05e9848cd4f1154abee17d4f265f012d upstream.

In smp_prepare_boot_cpu(), we invoke cpuinfo_store_boot_cpu to  store
the cpuinfo in a per-cpu ptr, before initialising the per-cpu offset for
the boot CPU. This patch reorders the sequence to make sure we initialise
the per-cpu offset before accessing the per-cpu area.

Commit 4b998ff1885eec ("arm64: Delay cpuinfo_store_boot_cpu") fixed the
issue where we modified the per-cpu area even before the kernel initialises
the per-cpu areas, but failed to wait until the boot cpu updated it's
offset.

Fixes: 4b998ff1885e ("arm64: Delay cpuinfo_store_boot_cpu")
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: debug: unmask PSTATE.D earlier
Will Deacon [Tue, 19 Jul 2016 14:07:37 +0000 (15:07 +0100)] 
arm64: debug: unmask PSTATE.D earlier

commit 2ce39ad15182604beb6c8fa8bed5e46b59fd1082 upstream.

Clearing PSTATE.D is one of the requirements for generating a debug
exception. The arm64 booting protocol requires that PSTATE.D is set,
since many of the debug registers (for example, the hw_breakpoint
registers) are UNKNOWN out of reset and could potentially generate
spurious, fatal debug exceptions in early boot code if PSTATE.D was
clear. Once the debug registers have been safely initialised, PSTATE.D
is cleared, however this is currently broken for two reasons:

(1) The boot CPU clears PSTATE.D in a postcore_initcall and secondary
    CPUs clear PSTATE.D in secondary_start_kernel. Since the initcall
    runs after SMP (and the scheduler) have been initialised, there is
    no guarantee that it is actually running on the boot CPU. In this
    case, the boot CPU is left with PSTATE.D set and is not capable of
    generating debug exceptions.

(2) In a preemptible kernel, we may explicitly schedule on the IRQ
    return path to EL1. If an IRQ occurs with PSTATE.D set in the idle
    thread, then we may schedule the kthread_init thread, run the
    postcore_initcall to clear PSTATE.D and then context switch back
    to the idle thread before returning from the IRQ. The exception
    return path will then restore PSTATE.D from the stack, and set it
    again.

This patch fixes the problem by moving the clearing of PSTATE.D earlier
to proc.S. This has the desirable effect of clearing it in one place for
all CPUs, long before we have to worry about the scheduler or any
exception handling. We ensure that the previous reset of MDSCR_EL1 has
completed before unmasking the exception, so that any spurious
exceptions resulting from UNKNOWN debug registers are not generated.

Without this patch applied, the kprobes selftests have been seen to fail
under KVM, where we end up attempting to step the OOL instruction buffer
with PSTATE.D set and therefore fail to complete the step.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
8 years agoarm64: KVM: VHE: Context switch MDSCR_EL1
Marc Zyngier [Tue, 19 Jul 2016 12:56:54 +0000 (13:56 +0100)] 
arm64: KVM: VHE: Context switch MDSCR_EL1

commit 4c47eb1c18c38b755eb4894a6ca38f834de3ec23 upstream.

The kprobe enablement work has uncovered that changes made by
a guest to MDSCR_EL1 were propagated to the host when VHE was
enabled, leading to unexpected exception being delivered.

Moving this register to the list of registers that are always
context-switched fixes the issue.

Fixes: 9c6c35683286 ("arm64: KVM: VHE: Split save/restore of registers shared between guest and host")
Reported-by: Tirumalesh Chalamarla <Tirumalesh.Chalamarla@cavium.com>
Tested-by: Tirumalesh Chalamarla <Tirumalesh.Chalamarla@cavium.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>